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chapter
3
Female Sexual
Anatomy,
Physiology, and
Response
68
MAIN
TOPICS
Female Sex Organs: What Are
They For? 69
Female Sexual Physiology 81
Female Sexual Response 90
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“I identify with the passion [of women], the strength, the
calmness, and the flexibility of being a woman. To me being
a woman is like being the ocean. The ocean is a powerful
thing, even at its calmest moments. It is a beauty that
commands respect. It can challenge even the strongest
men, and it gives birth to the smallest creatures. It is a
provider, and an inspiration; this is a woman and this is
what I am.”
—20-year-old female
“The more I think about things that annoy me about being a
woman, the more I realize that those annoyances are what
make it so special. When I get my period, it isn’t just a ‘monthly
curse’; it is a reminder that I can have children.”
—19-year-old female
“When I started my period, my father kept a bit of a distance.
How could I forget [that day]? The entire family was at my
aunt’s house, and no one had pads. You would think among
67 or so people one
female would have
a pad. I remember
crying and my
grandmother asking me what was
wrong. After I told
Student
her, she began to
Voices
laugh and said it
was a natural cycle.
I knew this from sixth-grade sexuality education class, but I still
didn’t want it. I was finally a woman.”
—19-year-old female
“I think I am a good sexual partner and enjoy pleasing a
woman. I especially love the foreplay that occurs between two
people because it gets the body more excited than just going
at it. I can go on forever with foreplay because I get to explore
my partner’s body, whether it is with my hands, lips, or tongue.”
—25-year-old male
A
lthough women and men are similar in many more ways than they
are different, we tend to focus on the differences rather than the similarities. Various cultures hold diverse ideas about exactly what it means to be
female or male, but virtually the only differences that are consistent are actual
physical differences, most of which relate to sexual structure and function.
In this chapter and the following one, we discuss both the similarities and
the differences in the anatomy (body structures), physiology (body functions),
and sexual response of females and males. This chapter introduces the sexual
structures and functions of women’s bodies, including hormones and the
menstrual cycle. We also look at models of sexual arousal and response, the
relationship of these to women’s experiences of sex, and the role of orgasm.
In Chapter 4, we discuss male anatomy and physiology, and in Chapter 5,
we move beyond biology to look at gender and the meanings we ascribe to
being female and male.
•
Female Sex Organs: What Are They For?
Anatomically speaking, all embryos are female when their reproductive structures begin to develop (see Figure 3.1). If it does not receive certain genetic
and hormonal signals, the fetus will continue to develop as a female. In humans
and most other mammals, the female, in addition to providing half the genetic
instructions for the offspring, provides the environment in which it can develop
until it becomes capable of surviving as a separate entity. She also nourishes
the offspring, both during gestation (the period of carrying the young in the
uterus) via the placenta and following birth via the breasts through lactation
(milk production).
In spite of what we do know, we haven’t yet mapped all of the basic body
parts of women, especially as they relate to the microprocesses of sexual
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Undifferentiated Stage Prior to 6th Week
Genital tubercle
Genital groove
Urogenital fold
Female
Labioscrotal swelling
Anus
7th– 8th Week
Male
Glans
(clitoris)
Glans
(penis)
Inner labial
fold
Urogenital
fold
Labial swelling
Vulval groove
Urethral groove
Scrotal swelling
Anus
Anus
Female
12th Week
Male
Penis
Clitoris
Labia
minora
Opening of urethra
Opening of
vagina
Urethral closure
Scrotum
Labia
majora
• FIGURE 3.1
Embryonic-Fetal Differentiation of
the External Reproductive Organs.
Female and male reproductive organs
are formed from the same embryonic
tissues. An embryo’s external genitals
are female in appearance until certain
genetic and hormonal instructions
signal the development of male
organs. Without such instructions, the
genitals continue to develop as female.
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•
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response. Such issues as the function of the G-spot, the role of orgasm, and
the placement of the many nerves that spider through the pelvic cavity still are
not completely understood. Add to these puzzles the types, causes, and treatments of sexual function problems and one can quickly see that the science of
sexual response is still emerging.
Clearly, the female sex organs serve a reproductive function. But they perform other functions as well. Significant to nearly all women are the sexual
parts that bring them pleasure; they may also serve to attract potential sexual
partners. Because of the mutual pleasure partners give each other, we can see
that sexual structures also serve an important role in human relationships.
People demonstrate their affection for one another by sharing sexual pleasure
and generally form enduring partnerships at least partially on the basis of
mutual sexual sharing. Let’s look at the features of human female anatomy and
physiology that provide pleasure to women and their partners and that enable
women to conceive and give birth.
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Symphysis pubis
Suspensory
ligament of clitoris
Corpora cavernosa
of clitoris
Glans clitoris
Prepuce of clitoris
Crura of clitoris
Frenulum of clitoris
Inner lips
External urethral
opening
Remnants of hymen
Vaginal opening
Ischiocavernosus
muscle
Vestibular bulb
Greater vestibular
gland and its
orifice
External anal
sphincter
muscle
Vestibule of vagina;
Frenulum of inner lips
Anus
• FIGURE 3.2
External Female Structures (Vulva)
External Structures (the Vulva)
The sexual and reproductive organs of both men and women are usually called
genitals, or genitalia, from the Latin genere, “to beget.” The external female
genitals are the mons pubis, the clitoris, the labia majora, and the labia minora,
collectively known as the vulva (see Figure 3.2). (People often use the word
“vagina” when they are actually referring to the vulva. The vagina is an internal
structure.)
The Mons Pubis The mons pubis (pubic mound), or mons veneris (mound
of Venus), is a pad of fatty tissue that covers the area of the pubic bone about
6 inches below the navel. Beginning in puberty, the mons is covered with pubic
hair. Because there is a rich supply of nerve endings in the mons, caressing it
can produce pleasure in most women.
The current practice of trimming and shaving pubic hair has become one
barometer of fashion (Ramsey, Sweeney, Fraser, & Oades, 2009). Over the past
few years, it has become commonplace in both sexes and for similar reasons:
aesthetic and psychosexual. Its acceptance and practice among women has
been revealed in a recent publication (Herbenick, Schick, Reece, Sanders, &
Fortenberry, 2010) which notes that a diverse range of pubic hair–grooming
practices appears to be an important component of sexual expression and
People will insist on treating the mons
“ veneris as though it were Mount Everest.
—Aldous Huxley
(1894–1963)
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participation in sexual activity. Findings were that pubic hair styles are diverse
and that it is more common than not for women to have at least some pubic
hair on their genitals. The authors of the study found that women’s total
removal of their pubic hair was associated with being young, being partnered,
having looked closely at one’s own genitals, cunnilingus, positive genital
self-image, and sexual function.
Implicated in the shift in cultural attitudes regarding pubic hair is Internetbased pornography, where removal has become the “norm.” This practice, however, is not new; many societies have decorated and sculpted their pubic hair
for centuries, while others have removed the hair to avoid body lice. Many
anecdotal reports on the removal of pubic hair highlight increased genital sensitivity and increased partner satisfaction. From a public health perspective, body
hair removal may be a risk factor for folliculitis (the inflammation of one or
more hair follicles) (Trager, 2006). On the other hand, a significant drop has
been found in the number of cases of pubic lice (Armstrong & Wilson, 2006).
If a woman chooses to shave, wax, or have her genitals pierced, she should use
only clean tools and exercise caution, since this is obviously a sensitive area.
Really that little dealybob is too far
from the hole. It should be built
“ away
right in.
—Loretta Lynn
(1935–)
Artwork often imitates
anatomy, as can be seen
in this painting titled Black Iris
(Georgia O’Keeffe, 1887–1986).
The Clitoris The clitoris (KLIH-tuh-rus) is considered the center of sexual
arousal. It contains a high concentration of sensory nerve endings and is exquisitely sensitive to stimulation, especially at the tip of its shaft, the glans clitoris.
A fold of skin called the clitoral hood covers the glans when the clitoris is not
engorged. Although the clitoris is structurally analogous to the penis (it is
formed from the same embryonic tissue), its sole function is sexual arousal. (The
penis serves the additional functions of urine excretion and semen ejaculation.)
The clitoris is a far more extensive structure than its visible part, the glans, would
suggest (Bancroft, 2009). The shaft of the clitoris is both an external and an
internal structure. The external portion is about 1 inch long and a quarter inch
wide. Internally, the shaft is divided into two branches called crura (KROO-ra;
singular, crus), each of which is about 3.5 inches long, which are the tips of
erectile tissue that attach to the pelvic bones. The crura contain two corpora
cavernosa (KOR-por-a kav-er-NO-sa), hollow chambers that fill
with blood and swell during arousal. The hidden erectile tissue of
the clitoris plus the surrounding muscle tissue all contribute to
muscle spasms associated with orgasm. When stimulated, the clitoris enlarges initially and then retracts beneath the hood just before
and during orgasm. With repeated orgasms, it follows the same
pattern of engorgement and retraction, although its swellings may
not be as pronounced after the initial orgasm. The role of the clitoris in producing an orgasm is discussed later in the chapter.
The Labia Majora and Labia Minora The labia majora (LAY-be-
a maJOR-a) (major lips) are two folds of spongy flesh extending from
the mons pubis and enclosing the labia minora, clitoris, urethral
opening, and vaginal entrance. The labia minora (minor lips) are
smaller folds within the labia majora that meet above the clitoris to
form the clitoral hood. The labia minora also enclose the urethral
and vaginal openings. They are smooth and hairless and vary quite
a bit in appearance from woman to woman. Another rich source of
sexual sensation, the labia are sensitive to the touch and swell during
sexual arousal, doubling or tripling in size and changing in color
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from flesh-toned to a deeper hue. The area enclosed by the labia minora is
referred to as the vestibule. During sexual arousal, the clitoris becomes erect, the
labia minora widen, and the vestibule (vaginal opening) becomes visible. Within
the vestibule, on either side of the vaginal opening, are two small ducts from the
Bartholin’s glands (or vestibular glands), which secrete a small amount of moisture during sexual arousal.
Internal Structures
The internal female sexual anatomy and reproductive organs include the vagina;
the uterus and its lower opening, the cervix; the ovaries; and the fallopian tubes.
(Figure 3.3 provides illustrations of the front and side views of the female
internal sexual anatomy.)
• FIGURE 3.3
Internal Female Sexual Structures
Fallopian tube
Fimbriae
Ovary
Uterus
Cervix
Bladder
Rectum
Pubic bone
Vagina
Approximate location
of the G-spot
Urethra
Crura
Clitoris (glans)
Anus
Hymen
Urinary opening
Vaginal opening (introitus)
Labia majora
Labia minora
(a) Side view
Fallopian tubes
Ovaries
Fimbriae
Uterus
Endometrium
Cervix
Os
(b) Front view
Vagina
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The external female genitalia
(vulva) can assume many
different colors, shapes, and
structures.
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The Vagina The vagina (va-JI-na), from the Latin word for sheath, is a flexible, muscular structure that extends 3–5 inches back and upward from the
vaginal opening. It is the birth canal through which an infant is born, allows
menstrual flow to pass from the uterus, and encompasses the penis or other
object during sexual expression. In the unaroused state, the walls of the vagina
are relaxed and collapsed together, but during sexual arousal, the inner two
thirds of the vagina expand while pressure from engorgement causes the many
small blood vessels that lie in the vaginal wall to produce lubrication. In
response to sexual stimulation, lubrication can occur within 10–30 seconds.
The majority of sensory nerve endings are concentrated in the lower third of
the vagina, or the introitus (in-TROY-tus). This part of the vagina is the most
sensitive to erotic pressure and touch. In contrast, the inner two thirds of the
vagina have virtually no nerve endings, which make it likely that a woman
cannot feel a tampon when it is inserted deep in the vagina. Although the
vaginal walls are generally moist, the wetness of a woman’s vagina can vary by
woman, by the stage of her menstrual cycle, and after childbirth or at menopause. Lubrication also increases substantially with sexual excitement. This
lubrication serves several purposes. First, it increases the possibility of conception by alkalinizing the normally acidic chemical balance in the vagina, thus
making it more hospitable to sperm, which die faster in acid environments.
Second, it can make penetration more pleasurable by reducing friction in the
vaginal walls. Third, the lubrication helps prevent small tears in the vagina
which, if they occur, can make the vagina more vulnerable to contracting HIV.
Prior to first intercourse or other form of penetration, the introitus is partially
covered by a thin membrane containing a relatively large number of blood vessels, the hymen (named for the Roman god of marriage). The hymen typically
has one or several perforations, allowing menstrual blood and mucous secretions
to flow out of the vagina (and generally allowing for tampon insertion). In many
cultures, it is (or was) important for a woman’s hymen to be intact on her wedding day. Blood on the nuptial bedsheets is taken as proof of her virginity. The
stretching or tearing of the hymen may produce some pain or discomfort and
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practically
speaking
Performing a Gynecological
Self-Examination
While reading this material, female readers may wish to
examine their own genitals and discover their unique
features. In a space that is comfortable for you, take time to
look at your vulva, or outer genitals, using a mirror and a good
light. The large, soft folds of skin with hair on them are the outer
lips, or labia majora. The color, texture, and pattern of this hair
vary widely among women. Inside the outer lips are the inner
lips, or labia minora. These have no hair and vary in size from
small to large and protruding. They extend from below the
vagina up toward the pubic bone, where they form a hood over
the clitoris. The glans may not be visible under the clitoral hood,
but it can be seen if a woman separates the labia minor and
retracts the hood. The size and shape of the clitoris, as well as
the hood, also vary widely among women. These variations have
nothing to do with a woman’s ability to respond sexually. You
may also find some cheesy white matter under the hood. This is
called smegma and is normal.
Below the clitoris is a smooth area and then a small hole. This
is the urinary opening, also called the meatus. Below the urinary
opening is the vaginal opening, which is surrounded by rings of
tissue. One of these, which you may or may not be able to
see, is the hymen. Just inside the vagina, on both sides, are the
Bartholin’s glands. These may secrete a small amount of mucus
during sexual excitement, but little else of their function is
known. If they are infected, they will be swollen, but otherwise
you won’t notice them. The smooth area between your vagina
and anus is called the perineum.
You can also examine your inner genitals, using a speculum,
flashlight, and mirror. A speculum is an instrument used to hold
the vaginal walls apart, allowing a clear view of the vagina and
cervix. You should be able to obtain a speculum and information
about doing an internal exam from a clinic that specializes in
women’s health or family planning.
It is a good idea to observe and become aware of what your
normal vaginal discharges look and feel like. Colors vary from
white to gray, and secretions change in consistency from thick
Examining your genitals can be an enlightening and useful
practice that can provide you with information about the
health of your body.
to thin and clear (similar to egg white that can be stretched
between the fingers) over the course of the menstrual cycle.
Distinct changes or odors, along with burning, bleeding between
menstrual cycles, pain in the pelvic region, itching, or rashes,
should be reported to a physician.
By inserting one or two fingers into the vagina and reaching
deep into the canal, it is possible to feel the cervix, or tip of the
uterus. In contrast to the soft vaginal walls, the cervix feels like
the end of a nose: firm and round.
In doing a vaginal self-exam, you may initially experience some
fear or uneasiness about touching your body. In the long run,
however, your patience and persistence will pay off in increased
body awareness and a heightened sense of personal health.
Once you’re familiar with the normal appearance of your
outer genitals, you can check for any changes, especially unusual
rashes, soreness, warts, or parasites, such as pubic lice, or “crabs.”
possibly some bleeding. Usually, the partner has little trouble inserting the penis
or other object through the hymen if he or she is gentle and there is adequate
lubrication. Prior to first intercourse, the hymen may be stretched or ruptured
by tampon insertion, by the woman’s self-manipulation, by a partner during
noncoital sexual activity, by accident, or by a health-care provider conducting a
routine pelvic examination. Hymenoplasty, a controversial procedure that reattaches the hymen to the vagina, is now sought by some women, particularly in
Muslim countries where traditionalists place a high value on a woman’s virginity, to create the illusion that they are still virgins. Hymen repair, also referred
to as “revirgination,” may also be performed for women who have been abused
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• FIGURE 3.4
The Grafenberg Spot (G-Spot).
To locate the Grafenberg spot, insert
two fingers into the vagina and press
deeply into its anterior wall.
Pubic
bone
Approximate location
of G-spot
Emptied bladder
Uterus
Cervix
Urethra
Urethral opening
(exit point for emission)
Anus
Anterior
vaginal wall
or those from cultures who risk a violent reaction from their partners. In spite
of its availability, the American College of Obstetricians and Gynecologists has
issued strong warnings to women that there is no evidence cosmetic genital
surgery is safe or effective (ACOG, 2007).
An area inside the body, surrounding the urethra, is what many women report
to be an erotically sensitive area, the Grafenberg spot, or G-spot. The name is
derived from Ernest Grafenberg, a gynecologist, who first discussed its erotic
significance. Located on the front wall of the vagina midway between the pubic
bone and the cervix on the vaginal side of the urethra (see Figure 3.4), this area
varies in size from a small bean to a half walnut. It can be located by pressing
one or two fingers into the front wall of a woman’s vagina. Coital positions such
as rear entry, in which the penis makes contact with the spot, may also produce
intense erotic pleasure (Ladas, Whipple, & Perry, 1982; Whipple & Komisaruk,
1999). A variety of responses have been reported by women who first locate this
spot. Initially, a woman may experience a slight feeling of discomfort or the need
to urinate, but shortly thereafter, the tissue may swell and a pleasurable feeling
may occur. Women who report orgasms as a result of stimulation of the G-spot
describe them as intense and extremely pleasurable (Perry & Whipple, 1981;
Whipple, 2002). Though an exact gland or site has not been found in all women,
nor do all women experience pleasure when the area is massaged, it has been
suggested that the orgasm occurring in the area called the G-spot could be caused
by the contact and connection of the richly innervated internal clitoris and the
anterior vaginal wall (Foldes & Buisson, 2009). More specifically, by using special
instruments and photography that measure changes in the vagina, it was found
that the displacement of the anterior vaginal wall that occurs with pressure of
the finger on this site, along with movement of the engorged and enlarged clitoris that occurs during sexual arousal, could provide close contact between the
internal root of the clitoris and the anterior vaginal wall and thereby lead to what
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is known as a G-spot orgasm, sometimes with accompanying emission of fluid.
This fluid, referred to as the “female ejaculate,” has the appearance of skim milk
and is chemically similar to seminal fluid, but different from urine (Komisaruk,
Whipple, Nasserzadeh, & Beyer-Flores, 2010). It has been suggested that the emitted fluid comes from the para-urethral glands, which recently have been named
the “female prostate gland.” The orgasm and emission that accompanies G-spot
stimulation is a healthy part of sexual expression and can be pleasurable.
The Uterus and Cervix The uterus (YU-te-rus), or womb, is a hollow, thickwalled, muscular organ held in the pelvic cavity by a number of flexible ligaments and supported by several muscles. It is pear-shaped, with the tapered end,
the cervix, extending down and opening into the vagina. If a woman has not
given birth, the uterus is about 3 inches long and 3 inches wide at the top; it
is somewhat larger in women who have given birth. The uterus expands during
pregnancy to the size of a volleyball or larger, to accommodate the developing
fetus. The inner lining of the uterine walls, the endometrium (en-doe-MEE-tree-um),
is filled with tiny blood vessels. As hormonal changes occur during the monthly
menstrual cycle, this tissue is built up and then shed and expelled through the
cervical os (opening), unless fertilization has occurred. In the event of pregnancy,
the pre-embryo is embedded in the nourishing endometrium.
In addition to the more or less monthly menstrual discharge, mucous secretions from the cervix also flow out through the vagina. These secretions tend to
be somewhat white, thick, and sticky following menstruation, becoming thinner
as ovulation approaches. At ovulation, the mucous flow tends to increase and
to be clear, slippery, and stretchy, somewhat like egg white. (Birth control using
cervical mucus to determine the time of ovulation is discussed in Chapter 11.)
The Ovaries On each side of the uterus, held in place by several ligaments,
is one of a pair of ovaries. The ovary is a gonad, an organ that produces
gametes (GA-meets), the sex cells containing the genetic material necessary for
reproduction. Female gametes are called oocytes (OH-uh-sites), from the Greek
words for egg and cell. (Oocytes are commonly referred to as eggs or ova
[singular, ovum]. Technically, however, the cell does not become an egg until
it completes its final stages of division following fertilization.) The ovaries are
the size and shape of large almonds. In addition to producing oocytes, they
serve the important function of producing hormones such as estrogen, progesterone, and testosterone. (These hormones are discussed later in this chapter.)
At birth, the female’s ovaries contain about half a million oocytes. During
childhood, many of these degenerate; then, beginning in puberty and ending
after menopause, a total of about 400 oocytes mature and are released during
a woman’s reproductive years. The release of an oocyte is called ovulation. The
immature oocytes are embedded in saclike structures called ovarian follicles.
The fully ripened follicle is called a vesicular or Graffian follicle. At maturation,
the follicle ruptures, releasing the oocyte. After the oocyte emerges, the ruptured follicle becomes the corpus luteum (KOR-pus LOO-tee-um) (from the
Latin for yellow body), a producer of important hormones; it eventually degenerates. The egg is viable for about 24 hours.
Girls got balls. They’re just a little higher
“ up, that’s all.
—Joan Jett (1960–)
The Fallopian Tubes At the top of the uterus are two tubes, one on each side,
known as fallopian tubes, uterine tubes, or oviducts. The tubes are about
4 inches long. They extend toward the ovaries but are not attached to them.
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Instead, the funnel-shaped end of each tube (the infundibulum) fans out into
fingerlike fimbriae (fim-BREE-ah), which drape over the ovary but may not
actually touch it. Tiny, hairlike cilia on the fimbriae and ampulla become active
during ovulation. Their waving motion, along with contractions of the walls of
the tube, transports the oocyte that has been released from the ovary into the
fallopian tube. Just within the infundibulum is the ampulla, the widened part
of the tube in which fertilization normally occurs if sperm and oocyte are there
at the same time. (The process of ovulation and the events leading to fertilization
are discussed later in this chapter; fertilization is covered in Chapter 12.)
Other Structures
There are several other important anatomical structures in the genital areas of
both men and women. Although they may not serve reproductive functions,
they may be involved in sexual activities. Some of these areas may also be
affected by sexually transmitted infections. In women, these structures include
the urethra, anus, and perineum. The urethra (yu-REE-thra) is the tube through
which urine passes; the urethral opening, or meatus, is located between the
clitoris and the vaginal opening. Between the vagina and the anus—the opening
of the rectum, through which excrement passes—is a diamond-shaped region
called the perineum (per-e-NEE-um). This area of soft tissue covers the muscles
and ligaments of the pelvic floor, the underside of the pelvic area extending
from the top of the pubic bone (above the clitoris) to the anus. (To learn more
about this muscle and Kegel exercises, which can strengthen it, see Chapter 14.)
The anus consists of two sphincters, which are circular muscles that open and
close like valves. The anus contains a dense supply of nerve endings that, along
with the tender rings at the opening, can respond erotically. (For additional
discussion about anal eroticism, see Chapter 9.) In sex play or intercourse involving the anus or rectum, care must be taken not to rupture the delicate tissues.
This may occur because of the lack of adequate lubrication or very rough anal
sex play. Anal sex, which involves insertion of the penis or other object into the
rectum, is potentially unsafe, as is vaginal sex, because abrasions of the tissue
provide easy passage for pathogens, such as HIV (the virus that causes AIDS),
to the bloodstream (see Chapter 16). To practice safer sex, partners who engage
in anal intercourse should use a latex condom with a water-based lubricant.
Uncorsetted, her friendly bust gives
“ promise of pneumatic bliss.
—T. S. Eliot
(1888–1965)
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The Breasts
With the surge of sex hormones that occurs during adolescence, the female breasts
begin to develop and enlarge (see Figure 3.5). The reproductive function of the
breasts is to nourish offspring through lactation, or milk production. A mature
female breast, also known as a mammary gland, is composed of fatty tissue and
15–25 lobes that radiate around a central protruding nipple. Around the nipple
is a ring of darkened skin called the areola (a-REE-o-la). Tiny muscles at the base
of the nipple cause it to become erect in response to touch, cold, or sexual arousal.
When a woman is pregnant, the structures within the breast undergo further
development. Directly following childbirth, in response to hormonal signals,
small glands within the lobes called alveoli (al-VEE-a-lee) begin producing
milk. The milk passes into ducts, each of which has a dilated region for storage;
the ducts open to the outside at the nipple. (Breastfeeding is discussed in
Chapter 12.) During lactation, a woman’s breasts increase in size from enlarged
glandular tissues and stored milk. Because there is little variation in the amount
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• FIGURE 3.5
Suspensory
ligaments
Fat
Ribs
The Female Breast. Front and
cross-section views.
Chest wall
Areola
Nipple
Mammary
glands
Milk ducts
Alveoli
of glandular tissue among women, the amount of milk produced does not vary
with breast size. In women who are not lactating, breast size depends mainly
on fat content, which is determined by hereditary factors.
In the Western culture, women’s breasts capture a significant amount of attention and serve an erotic function. Many, but not all, women find breast stimulation intensely pleasurable, whether it occurs during breastfeeding or sexual contact.
Partners tend to be aroused by both the sight and the touch of women’s breasts.
Although there is no basis in reality, some believe that large breasts denote greater
sexual responsiveness than small breasts. (See Chapter 13 for a discussion of breast
enhancement.) (Table 3.1 provides a summary of female sexual anatomy.)
Western culture tends to
be ambivalent about breasts
and nudity. Many people are
comfortable with artistic
portrayals of the nude
female body.
Female Sex Organs: What Are They For?
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Summary Table of Female Sexual Anatomy
External Structures (Vulva)
Mons pubis (mons veneris)
Fatty tissue that covers the area of the pubic bone
Clitoris
Center of sexual arousal
Clitoral hood
Covers the glans clitoris when the clitoris is not engorged
Crura (singular, crus)
Tips of erectile tissue that attach to the pelvic bones
Corpora cavernosa
Hollow chambers that fill with blood and swell during sexual arousal
Labia majora (major lips)
Two folds of spongy flesh that extend from the mons pubis and run downward along the sides
of the vulva
Labia minora (minor lips)
Smaller, hairless folds within the labia majora that meet above the clitoris to form the clitoral hood
Vestibule (vaginal opening)
Area enclosed by the labia minora
Bartholin’s glands
Glands that secrete a small amount of moisture during sexual arousal
Internal Structures
Vagina (birth canal)
Flexible, muscular structure in which menstrual flow and babies pass
Introitus
The lower part of the vagina
Hymen
Thin membrane that partially covers the introitus and contains a relatively large number of blood vessels
Grafenberg spot (G-spot)
Located on the front wall of the vagina, an erotically sensitive area that may produce intense erotic
pleasure and a fluid emission in some women
Uterus (womb)
Hollow, thick-walled muscular organ in which a fertilized ovum implants and develops until birth
Cervix
Lower end of the uterus that extends down and opens to the vagina
Endometrium
Inner lining of the uterine wall to which the fertilized egg attaches; partly discharged (if pregnancy
does not occur) with the menstrual flow
Os
Opening to the cervix
Ovary (gonad)
Organ that produces gametes (see below)
Gametes
Sex cells containing the genetic material necessary for reproduction; also referred to as oocytes,
eggs, ova (singular, ovum)
Ovarian follicles
Saclike structures that contain the immature oocytes
Corpus luteum
Tissue formed from a ruptured ovarian follicle that produces important hormones after the oocyte
emerges
Fallopian tubes (oviducts)
Uterine tubes that transport the oocyte from the ovary to the uterus
Infundibulum
Funnel-shaped end of each fallopian tube
Fimbriae
Fingerlike projections that drape over the ovary and help transport the occyte from the ovary into
the fallopian tube
Cilia
Tiny, hairlike structures that provide waving motion to help transport the oocyte within the fallopian
tube to the ovary
Ampulla
Widened part of the fallopian tube in which fertilization normally occurs
Other Structures
Urethra
80
Tube through which urine passes
Urethral opening (meatus)
Opening in the urethra, through which urine is expelled
Anus
Opening in the rectum, through which excrement passes
Perineum
Area that lies between the vaginal opening and the anus
Pelvic floor
Underside of the pelvic area, extending from the top of the pubic bone (above the clitoris) to the anus
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During ovulation, the ovarian
follicle swells and ruptures,
releasing the mature oocyte to
begin its journey through the
fallopian tube.
•
Female Sexual Physiology
Just how do the various structures of the female anatomy function to produce
the menstrual cycle? The female reproductive cycle can be viewed as having
two components (although, of course, multiple biological processes are
involved): (1) the ovarian cycle, in which eggs develop, and (2) the menstrual,
or uterine, cycle, in which the womb is prepared for pregnancy. These cycles
repeat approximately every month for about 35 or 40 years. The task of directing these processes belongs to a class of chemicals called hormones.
Reproductive Hormones
Hormones are chemical substances that serve as messengers, traveling within the
body through the bloodstream. Most hormones are composed of either amino
acids (building blocks of proteins) or steroids (derived from cholesterol). They are
produced by the ovaries and the endocrine glands—the adrenals, pituitary, and
hypothalamus. Hormones assist in a variety of tasks, including development of
the reproductive organs and secondary sex characteristics during puberty, regulation of the menstrual cycle, maintenance of pregnancy, initiation and regulation
of childbirth, initiation of lactation, and, to some degree, the regulation of libido
(li-BEE-doh; sex drive or interest). Hormones that act directly on the gonads are
known as gonadotropins (go-nad-a-TRO-pins). Among the most important of
the female hormones are the estrogens, which affect the maturation of the reproductive organs, menstruation, and pregnancy, and progesterone, which helps to
maintain the uterine lining until menstruation occurs. (The principal hormones
involved in a woman’s reproductive and sexual life and their functions are described
in Table 3.2.) (Testosterone is discussed later in this chapter.)
The Ovarian Cycle
The development of female gametes is a complex process that begins even before
a woman is born. In infancy and childhood, the cells develop into ova (eggs).
During puberty, hormones trigger the completion of the process of oogenesis
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Female Sex Hormones
Hormone
Where Produced
Functions
Estrogen (including estradiol,
estrone, estriol)
Ovaries, adrenal glands, placenta
(during pregnancy)
Promotes maturation of reproductive organs,
development of secondary sex characteristics, and
growth spurt at puberty; regulates menstrual
cycle; sustains pregnancy; maintains libido
Progesterone
Ovaries, adrenal glands, placenta
Promotes breast development, maintains uterine
lining, regulates menstrual cycle, sustains
pregnancy
Gonadotropin-releasing hormone
(GnRH)
Hypothalamus
Promotes maturation of gonads, regulates
menstrual cycle
Follicle-stimulating hormone (FSH)
Pituitary
Regulates ovarian function and maturation of
ovarian follicles
Luteinizing hormone (LH)
Pituitary
Assists in production of estrogen and
progesterone, regulates maturation of ovarian
follicles, triggers ovulation
Human chorionic gonadotropin (HCG)
Embryo and placenta
Helps sustain pregnancy
Testosterone
Adrenal glands and ovaries
Helps stimulate sexual desire
Oxytocin
Hypothalamus
Stimulates uterine contractions during childbirth and
possibly during orgasm, promotes milk let-down
Prolactin
Pituitary
Stimulates milk production
Prostaglandins
All body cells
Mediates hormone response, stimulates muscle
contractions
(oh-uh-JEN-uh-sis), literally, “egg beginning” (see Figure 3.6). The oocyte, otherwise referred to as germ cell or immature ovum, marks the start of mitosis,
the process by which a cell duplicates the chromosome in its cell nucleus.
Oogenesis results in the formation of both primary oocytes, before birth, and
as secondary oocytes after it and as part of ovulation. This process, called the
ovarian cycle (or menstrual cycle), continues until a woman reaches menopause.
The ovarian cycle averages 28 days in length, although there is considerable
variation among women, ranging from 21 to 40 days. In their own particular
cycle length after puberty, however, most women experience little variation.
Generally, ovulation occurs in only one ovary each month, alternating between
the right and left sides with each successive cycle. If a single ovary is removed,
the remaining one begins to ovulate every month. The ovarian cycle has three
phases: follicular (fo-LIK-u-lar), ovulatory (ov-UL-a-tor-ee), and luteal (LOOtee-ul) (see Figure 3.7). As an ovary undergoes its changes, corresponding
changes occur in the uterus. Menstruation marks the end of this sequence of
hormonal and physical changes in the ovaries and uterus.
The Follicular Phase On the first day of the cycle, gonadotropin-releasing
hormone (GnRH) is released from the hypothalamus. GnRH begins to stimulate the pituitary to release follicle-stimulating hormone (FSH) and luteinizing hormone (LH), initiating the follicular phase. During the first 10 days,
10–20 ovarian follicles begin to grow, stimulated by FSH and LH. In 98–99%
of cases, only one of the follicles will mature completely during this period.
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• FIGURE 3.6
Oogonium
(46 chromosomes)
Oogenesis. This diagram charts the
development of an ovum, beginning
with embryonic development of the
oogonium and ending with fertilization
of the secondary oocyte, which then
becomes the diploid zygote. Primary
oocytes are present in a female at
birth; at puberty, hormones stimulate
the oocyte to undergo meiosis.
mitosis
Mitosis
Many oogonia
growth and differentiation
Primary oocyte
(46 chromosomes)
before birth
after birth
Meiosis I
sexual maturity
meiosis
ovulation
First polar body
Secondary oocyte
(23 chromosomes)
Fertilization
Sperm
(23 chromosomes)
Meiosis II
meiosis
meiosis
Second
polar body
Diploid zygote
Polar bodies degenerating
(The maturation of more than one oocyte is one factor in multiple births.) All
the developing follicles begin secreting estrogen. Under the influence of FSH
and estrogen, the oocyte matures, bulging from the surface of the ovary. This
may also be referred to as the proliferative phase.
The ovulatory phase begins at about day 11 of the cycle
and culminates with ovulation at about day 14. Stimulated by an increase of
LH from the pituitary, the primary oocyte undergoes cell division and
becomes ready for ovulation. The ballooning follicle wall thins and ruptures,
and the oocyte enters the abdominal cavity near the beckoning fimbriae.
Ovulation is now complete. Some women experience a sharp twinge, called
Mittelschmerz, on one side of the lower abdomen during ovulation. A very
slight bloody discharge from the vagina may also occur. Occasionally, more
than one ovum is released. If two ova are fertilized, nonidentical twins will
result. If one egg is fertilized and divides into two separate zygotes, identical
twins will develop.
Ovulatory Phase
The Luteal Phase Following ovulation, estrogen levels drop rapidly, and the
ruptured follicle, still under the influence of increased LH, becomes a corpus
luteum, which secretes progesterone and small amounts of estrogen. Increasing
levels of these hormones serve to inhibit pituitary release of FSH and LH.
Unless fertilization has occurred, the corpus luteum deteriorates. In the event
of pregnancy, the corpus luteum maintains its hormonal output, helping to
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Menstrual Phase
Follicular Phase
(also called the Proliferative Phase)
(Menstruation)
(Follicle development)
Fallopian tube
Oocyte disintegrates
Uterine lining
Uterine lining renews
Ovary
Fimbriae
Uterus
Uterine lining
sloughs off and passes
out of the body through
the cervix and vagina
Maturing
oocyte in
follicle
Immature
oocytes
Cervix
Vagina
Ovulatory Phase
Luteal Phase
Uterine lining thickens
Oocyte travels through tube
Remaining cells
of follicle develop
into corpus luteum
Oocyte is released
Lining continues to thicken
• FIGURE 3.7
Ovarian and Menstrual Cycles.
The ovarian cycle consists of the
activities within the ovaries and the
development of oocytes; it includes
the follicular, ovulatory, and luteal
phases. The menstrual cycle consists
of processes occurring in the uterus.
Hormones regulate these cycles.
sustain the pregnancy. The hormone human chorionic gonadotropin (HCG)—
similar to LH—is secreted by the embryo and signals the corpus luteum to
continue until the placenta has developed sufficiently to take over hormone
production.
The luteal phase typically lasts from day 14 (immediately after ovulation)
through day 28 of the ovarian cycle. Even when cycles are more or less than
28 days, the duration of the luteal phase remains the same; the time between
ovulation and the end of the cycle is always 14 days. At this point, the ovarian
hormone levels are at their lowest, GnRH is released, and FSH and LH levels
begin to rise.
The Menstrual Cycle
As hormone levels decrease following the degeneration of the corpus luteum,
the uterine lining (endometrium) is shed because it will not be needed to help
sustain the fertilized ovum. The shedding of endometrial tissue and the bleeding
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that accompanies it are, collectively, a monthly event in the lives of women from
puberty through menopause. Cultural and religious attitudes, as well as personal
experience, influence our feelings about this phenomenon. (The physical and
emotional effects of menstruation are discussed later in this section. The onset
of menstruation and its effect on a woman’s psychosexual development are discussed in Chapter 6. Menopause is discussed in Chapter 7.)
Most American women who menstruate use sanitary pads, panty liners, or
tampons to help absorb the flow of menstrual blood. While pads and panty
liners are used outside the body, tampons are placed inside the vagina. For a
wide variety of reasons, including environmental concerns, comfort, chemical
residues, and toxic shock syndrome (a bacterial infection that can occur in
menstruating women and cause a person to go into shock; discussed in
Chapter 13), women are turning to alternative means for catching menstrual flow.
While some Americans may question the use of alternative products, across
time and culture a wide variety of methods have been used to absorb the flow of
blood. Cloth menstrual pads are reusable, washable, and quite comfortable. For
those desiring to wear something internally, other products, called The Keeper,
DivaCuptm, or Instead, consist of a menstrual cup that is held in place by suction
in the lower vagina and acts to collect menstrual fluid. Some women have used
the diaphragm or cervical cap in a similar manner. Reusable sea sponges can work
like tampons in absorbing blood. Boiling the sponge before use and between uses
can help to rid it of possible ocean pollutants and help to keep it sanitary. Sewing
or tying a piece of cotton string on the sponge for easy retrieval is suggested. Most
likely, the majority of American women will continue to rely on more widely
available and advertised commercial tampons or sanitary pads; however, alternatives provide women with an opportunity to take charge of how they respond to
their menstrual flow and the environmental impacts of that decision.
The menstrual cycle (or uterine cycle), is divided into three phases: menstrual, proliferative, and secretory. What occurs within the uterus is inextricably
related to what is happening in the ovaries, but only in their final phases do
the two cycles actually coincide (see Figure 3.8).
An array of choices that collect
and absorb menstrual flow are
now available to women.
The Menstrual Phase With hormone levels low because of the degeneration
of the corpus luteum, the outer layer of the endometrium becomes detached
from the uterine wall. The shedding of the endometrium marks the beginning
of the menstrual phase. This endometrial tissue, along with mucus, other cervical and vaginal secretions, and a small amount of blood (2–5 ounces per cycle),
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• FIGURE 3.8
The Menstrual Cycle, Ovarian
Cycle, and Hormone Levels. This
chart compares the activities of the
ovaries and uterus and shows the
relationship of blood hormone levels
to these activities.
Highest intimacy
and sex drive
Pituitary hormone
levels in bloodstream
LH
FSH
Ovarian hormone
levels in bloodstream
Estrogen
Progesterone
Testosterone/Androgen
Ovarian cycle
Follicle
Ovum
Corpus luteum
degenerates
Menstrual cycle
Menstrual
flow
Menses
Endometrium
Menstrual flow
Estrogenic
phase
Day 1
Ovulation
Day 14
Progestational
phase
Menses
Day 28
is expelled through the vagina. The menstrual flow, or menses (MEN-seez), generally occurs over a period of 3–5 days. FSH and LH begin increasing around
day 5, marking the end of this phase. A girl’s first menstruation is known as
menarche (MEH-nar-kee).
The Proliferative Phase The proliferative phase lasts about 9 days. During this
time, the endometrium thickens in response to increased estrogen. The mucous
membranes of the cervix secrete a clear, thin mucus with a crystalline structure that
facilitates the passage of sperm. The proliferative phase ends with ovulation.
The Secretory Phase During the first part of the secretory phase, with the help
of progesterone, the endometrium begins to prepare for the arrival of a fertilized
ovum. Glands within the uterus enlarge and begin secreting glycogen, a cell
nutrient. The cervical mucus thickens and starts forming a plug to seal off the
uterus in the event of pregnancy. If fertilization does not occur, the corpus luteum
begins to degenerate, as LH levels decline. Progesterone levels then fall, and the
endometrial cells begin to die. The secretory phase lasts 14 days, corresponding with
the luteal phase of the ovarian cycle. It ends with the shedding of the endometrium.
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Menstrual Synchrony Women who live or work together often report developing similarly timed menstrual cycles (Cutler, 1999). Termed menstrual
synchrony, this phenomenon appears to be related to the sense of smell—more
specifically, a response to pheromones, chemical substances secreted into the
air. Though there is considerable controversy among researchers as to whether
the phenomenon actually exists, if it does, there could be implications for birth
control, sexual attraction, and other aspects of women’s lives. (Pheromones are
discussed later in the chapter.)
Menstrual Effects American women have divergent attitudes toward menstrua-
tion. For some women, menstruation is a problem; for others, it is simply a fact
of life that creates little disruption. For individual women, the problems associated
with their menstrual period may be physiological, emotional, or practical. The vast
majority of menstruating women notice at least one emotional, physical, or behavioral change in the week or so prior to menstruation. Most women describe the
changes negatively: breast tenderness and swelling, abdominal bloating, irritability,
cramping, depression, or fatigue. Some women also report positive changes such
as increased energy, heightened sexual arousal, or a general feeling of well-being.
For most women, changes during the menstrual cycle are usually mild to moderate; they appear to have little impact on their lives. The most common problems
associated with menstruation are discussed below.
Menstrual Period Slang
“ that time of the month
monthlies
the curse
female troubles
a visit from my friend
a visit from Aunt Flo
a visit from George
on the rag
on a losing streak
falling off the roof
Premenstrual Syndrome A collection of physical, emotional, and psychological changes that may occur 7–14 days before a woman’s menstrual period
is known as premenstrual syndrome (PMS). These symptoms disappear soon
after the start of menstrual bleeding. Though no one knows for sure what causes
PMS, it seems to be linked to alterations in the levels of sex hormones and
brain chemicals, or neutrotransmitters.
Controversy exists over the difference between premenstrual discomfort and
true PMS. Premenstrual discomfort is a common occurrence, affecting about
75% of all menstruating women (InteliHealth, 2005). Only about 3–8% of
women, however, have symptoms that are severe enough to be labeled PMS.
While some doctors equate premenstrual dysphoric disorder to PMS, others
use a less stringent definition for PMS, which includes mild to moderate symptoms. Symptoms of PMS fall into two categories: physical symptoms, which
may include bloating, breast tenderness, swelling and weight gain, headaches,
cramping, migraine headaches, and food cravings; and psychological and emotional symptoms, which include fatigue, depression, irritability, crying, and
changes in libido. For many, symptoms may be worse some months and better
other ones. It may also be comforting to know that in most women, PMS
symptoms begin to subside after the age of 35 and at menopause.
Menorrhagia At some point in her menstrual life, nearly every woman experiences heavy or prolonged bleeding during her menstrual cycle, also known as
menorrhagia. Although heavy menstrual bleeding is common among most
women, only a few experience blood loss severe enough for it to be defined as
menorrhagia. Signs and symptoms may include a menstrual flow that soaks
through one or more sanitary pads or tampons every hour for several consecutive
hours, the need to use double sanitary protection throughout the menstrual flow,
menstrual flow that includes large blood clots, and/or heavy menstrual flow that
interferes with the regular lifestyle. Though the cause of heavy menstrual bleeding
is unknown, a number of conditions may cause menorrhagia, including hormonal
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imbalances, uterine fibroids, having an IUD, cancer, or certain medications. The
combined effect of hormonal imbalances and uterine fibroids accounts for 80%
of all cases of menorrhagia. Excessive or prolonged menstrual bleeding can lead
to iron deficiency anemia and other medical conditions; thus, it is advisable for
women with this problem to seek medical care and treatment.
Dysmenorrhea While menstrual cramps are experienced by some women
before or during their periods, a more persistent, aching, and serious pain sufficient to limit a woman’s activities is called dysmenorrhea. There are two types
of dysmenorrhea. Primary dysmenorrhea is not associated with any diagnosable
pelvic condition. It is characterized by pain that begins with (or just before)
uterine bleeding when there is an absence of pain at other times in the cycle.
It can be very severe and may be accompanied by nausea, weakness, or other
physical symptoms. In secondary dysmenorrhea, the symptoms may be the
same, but there is an underlying condition or disease causing them; pain may
not be limited to the menstrual phase alone. Secondary dysmenorrhea may be
caused by pelvic inflammatory disease (PID), endometriosis, endometrial cancer,
or other conditions that should be treated. (See Chapters 13 and 15.)
The effects of dysmenorrhea can totally incapacitate a woman for several hours
or even days. Once believed to be a psychological condition, primary dysmenorrhea is now known to be caused by high levels of prostaglandins (pros-ta-GLANdins), a type of hormone with a fatty-acid base that is found throughout the body.
Drugs like ibuprofen (Motrin and Advil) relieve symptoms by inhibiting the production of prostaglandins. Some doctors may prescribe birth control pills.
Amenorrhea When women do not menstruate for reasons other than aging,
the condition is called amenorrhea (ay-meh-neh-REE-a). Principal causes of
amenorrhea are pregnancy and breastfeeding. Lack of menstruation, if not a
result of pregnancy or nursing, is categorized as either primary or secondary
amenorrhea. Women who have passed the age of 16 and never menstruated
are diagnosed as having primary amenorrhea. It may be that they have not yet
reached their critical weight (when an increased ratio of body fat triggers menstrual cycle–inducing hormones) or that they are hereditarily late maturers. But
it can also signal hormonal deficiencies, abnormal body structure, or an intersex condition or other genital anomaly that makes menstruation impossible.
Most primary amenorrhea can be treated with hormone therapy.
Secondary amenorrhea exists when a previously menstruating woman stops
menstruating for several months. If it is not due to pregnancy, breastfeeding,
or the use of hormonal contraceptives, the source of secondary amenorrhea
may be found in stress, lowered body fat, heavy physical training, cysts or
tumors, disease, or hormonal irregularities. Anorexia (discussed in Chapter 13)
is a frequent cause of amenorrhea. If a woman is not pregnant, is not breastfeeding, and can rule out hormonal contraceptives as a cause, she should see
her health-care practitioner if she has gone 3 months without menstruating.
Lifestyle changes or treatment of the underlying condition can almost always
correct amenorrhea, unless it is caused by a congenital anomaly. Because there
is no known harm associated with amenorrhea, the condition is corrected when
an underlying problem presents itself or it causes a woman psychological distress.
Sexuality and the Menstrual Cycle Although studies have tried to determine whether there is a biologically based cycle of sexual interest and activity
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practically
speaking
Many factors can influence the way we experience the
changes that occur over the course of the menstrual cycle.
While the vast majority of women feel few and minor changes,
others experience changes that are uncomfortable and
debilitating. The variations can be significant in any one woman
and from month to month. For women, recognizing their menstrual patterns, learning about their bodies, and recognizing and
dealing with existing difficulties can be useful in heading off or
easing potential problems. Different remedies work for different
women. We suggest that you try varying combinations of them
and keep a record of your response to each. Following are some
common changes that occur during the menstrual cycle and
self-help means to address them.
For Vaginal Changes
The mucous membranes lining the walls of the vagina normally
produce clear, white, or pale yellow secretions. These secretions
pass from the cervix through the vagina and vary in color,
consistency, odor, and quantity, depending on the phase of the
menstrual cycle, the woman’s health, and her unique physical
characteristics. It is important for you to observe your secretions
periodically and note any changes, especially if symptoms
accompany them. Because self-diagnosis of unusual discharges
is inaccurate over half the time, it is wise to go ahead with selftreatment only after a diagnosis is made by a health-care
practitioner. Call a health professional if you feel uncertain or
suspicious and/or think you may have been exposed to a
sexually transmitted infection.
Here are some simple guidelines that may help a woman
avoid getting vaginitis:
4. Wear cotton underpants with a cotton crotch. Nylon does
not “breathe,” and it allows heat and moisture to build up,
creating an ideal environment for infectious
organisms to reproduce.
5. If you use a vaginal lubricant, be sure it is water-soluble.
Oil-based lubricants such as Vaseline encourage bacterial
growth.
6. Socialize with others or go to a support group to help reduce
the stress that may cause or exacerbate the infection.
For Premenstrual Changes
1. Consume a well-balanced diet, with plenty of whole-grain
cereals, fruits, and vegetables.
2. Moderate your intake of alcohol, avoid tobacco, and get
sufficient sleep.
3. Exercise at least 30–45 minutes a day. Aerobic exercise brings
oxygen to body tissues and stimulates the production of
endorphins, chemical substances that help promote feelings
of well-being.
For Cramps
1. Relax and apply heat by using a heating pad or hot-water
bottle (or, in a pinch, a cat) applied to the abdominal area
may help relieve cramps; a warm bath may also help.
2. Get a lower-back or other form of massage, such as acupressure, or Shiatsu.
1. Avoid douching and vaginal deodorants, especially
deodorant suppositories or tampons. They upset the natural
chemical balance of the vagina.
3. Take prostaglandin inhibitors, such as aspirin and ibuprofen,
to reduce cramping of the uterine and abdominal muscles.
Aspirin increases menstrual flow slightly, whereas ibuprofen
reduces it. Stronger antiprostaglandins may be prescribed by
your health-care practitioner.
2. Maintain good genital hygiene by washing the labia and
clitoris regularly (about once a day) with mild soap.
4. Having an orgasm (with or without a partner) is reported by
some women to relieve menstrual congestion and cramping.
3. After a bowel movement, wipe the anus from front to back, away
from the vagina, to prevent contamination with fecal bacteria.
When symptoms are severe, further medical evaluation is
needed.
in women that correlates with the menstrual cycle (such as higher interest
around ovulation), the results have been varied. There is also variation in how
people feel about sexual activity during different phases of the menstrual cycle.
There has been a general taboo in our culture, as in many others, against
sexual intercourse during menstruation. This taboo may be based on religious
or cultural beliefs. Among Orthodox Jews, for example, women are required
to refrain from intercourse for 7 days following the end of menstruation. They
may then resume sexual activity after a ritual bath, the mikvah. Contact with
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blood may make some people squeamish. Some women, especially at the beginning of their period, feel bloated or uncomfortable; they may experience breast
tenderness or a general feeling of not wanting to be touched. Others may find
that sexual activity helps relieve menstrual discomfort.
For some couples, merely having to deal with the logistics of bloodstains, bathing, and laundry may be enough to discourage them from intercourse at this time.
For many people, however, menstrual blood holds no special connotation. In a
study of 108 women aged 18–23, females described their experiences with sexuality during menstruation. Nearly one half, most of whom were in committed
relationships, stated they had sexual activity during their menstrual cycle (Allen
& Goldberg, 2009). Young adults who were comfortable with menstrual sex saw
it as just another part of a committed intimate relationship. It is important to
note that although it is unusual, conception can occur during menstruation. Some
women find that a diaphragm or menstrual cup can collect the menstrual flow.
Menstrual cups, however, are not a contraceptive. It is not recommended that
women engage in intercourse while a tampon is inserted because of possible injury
to the cervix. And inventive lovers can, of course, find many ways to give each
other pleasure that do not require putting the penis into the vagina.
•
Female Sexual Response
The ways in which individuals respond to sexual arousal are highly varied.
Women’s sexuality, though typically thought of as personal and individual, is
significantly influenced by the social groups to which women belong. Sociocultural variables include gender, religious preference, class, educational attainment, age, marital status, race, and ethnicity. For many women, gender—the
social and cultural characteristics associated with being male or female—is
probably the most influential variable in shaping their sexual desires, behaviors,
and partnerships. Because gender is largely defined by cultural expectations,
women’s sexual experiences must be understood in terms of cultural, political,
and relational forces. New research into the anatomy and physiology of sexuality has helped us to increase our understanding of orgasm. By looking beyond
the genitals to the central nervous system, where electrical impulses travel from
the brain to the spinal cord, researchers are examining nerves and pathways to
better understand the biology of the orgasm. What is probably most critical to
all of these functions are the ways we interpret sexual cues.
Though scientific research has contributed much to our understanding of
sexual arousal and response, there is still much to be learned. One way in which
researchers investigate and describe phenomena is through the creation of models, hypothetical descriptions used to study or explain something. Although
models are useful for promoting general understanding or for assisting in the
treatment of specific clinical problems, we should remember that they are only
models. It may be helpful to think of sexual functioning as interconnected,
linking desire, arousal, orgasm, and satisfaction. Turbulence or distraction at
any one point affects the functioning of the others.
Passion, though a bad regulator, is a
“ powerful spring.
—Ralph Waldo Emerson
(1803–1882)
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Sexual Response Models
A number of sexologists have attempted to outline the various physiological
changes that both men and women undergo when they are sexually stimulated.
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think
about it
Sexual Fluidity: Women’s Variable
Sexual Attractions
When the media report stories about same-sex lovers, such
as actress Anne Heche leaving Ellen DeGeneres for a man,
Cynthia Nixon (from Sex and the City) leaving her male
partner of 15 years for a woman, and Julie Cypher leaving a
heterosexual marriage for Melissa Etheridge then later leaving her for a man, what are your responses? Are these incidents
simply flukes? Are the women confused? Bisexual? None of these,
according to Lisa Diamond, professor of psychology and gender
studies at the University of Utah. Rather, she has coined the term
“sexual fluidity” to describe sexual desires and attractions as
situation-dependent in sexual responsiveness (Diamond, 2008).
Based on her own research and analysis of animal mating
and women’s sexuality, Diamond suggests that female desire
may be dictated by both intimacy and emotional connection.
She came to this conclusion after 10 years following the erotic
attractions of nearly 100 young women who, at the start of her
work, identified themselves as lesbian, bisexual, or refused a
label. From her analysis of their shifts between sexual identities
and descriptions of their erotic lives, Diamond suggests that for
her participants and possibly for women on the whole, desire is
malleable, embedded in the nature of female desire, and cannot
be captured by asking women to categorize their attractions.
Among the women in her study who called themselves lesbian,
one third reported attraction solely to women while the other
two thirds revealed periodic and genuine desire and attraction
to men. When discussing sexual orientation, Diamond sees significance in the fact that many of her subjects agreed with the
statement “I am the kind of person who becomes physically
attracted to the person rather than their gender.”
Thus it is, in the cases of Diamond’s subjects, that emotional
closeness overrode innate orientation, resulting in attraction and
desire. This concept seems to violate the core underlying assumption of our model of sexuality: that sexual orientation is defined
by sexual behavior. Not long ago, the sexualities—heterosexuality, homosexuality, and even bisexuality—were categorical. Sexual
attraction and desire, sexual behavior, and sexual identity were
assumed to be congruent; same-gender sexual attraction/
behavior assumed a gay, lesbian, or bisexual identity; and other
sexual attraction/behavior assumed a heterosexual identity
(Schecter, 2009). Now, Diamond’s work along with others’, reveals
this may be true for some women, but not true for all. In fact,
desire/behavior and orientation/identity do not always match up.
The more scholars learn about sexual desire, the more it
becomes apparent that it involves a complex interplay among
biological, environmental, psychological, cultural, and
interpersonal factors. Evidence points to three characteristics
about desire: (1) It is both hormonally and situationally driven,
(2) individuals are often unaware of the full range of their desires, and (3) women’s sexual desires show more variability than
do men’s. Probably the largest review of all the published data
on the subject around the variability of women’s sexual desires
was published by Roy Baumeister (2000), professor of psychology
at Florida State University. The study found that women show
greater variability than men in a wide range of sexual behaviors,
including desired frequency of sex, preferred contexts for
sexual behavior, types and frequency of fantasy, and desirable
partner characteristics. Nevertheless, sex researchers still do not
understand the mechanisms that underlie sexual fluidity.
While tremendous strides have been made to foster greater
acceptance of a diversity of sexual expression, sexual minorities
as a whole still remain isolated and unsupported. Textbooks,
media, and culture continue to assume that there is a fixed
model of same-sex sexuality, in spite of the fact that many
individuals know differently. Although the notion of sexual
fluidity may be confusing, frightening, or threatening to some,
it does offer one more variable to the broad spectrum of sexual
expression of which humans are capable and can celebrate.
Think Critically
1. Is sexual orientation innate and/or fixed? If so, at what
age? How do you know this?
2. Have you experienced sexual fluidity? If so, what were
your reactions?
3. What would you do if your same-sex or other-sex
best friend told you that he or she was romantically
interested in you?
Three important models are described here. The sequence of changes and patterns
that take place in the body during sexual arousal is referred to as the sexual
response cycle. Masters and Johnson’s four-phase model of sexual response
identifies the significant stages of response as excitement, plateau, orgasm, and
resolution (see Figure 3.9). Helen Singer Kaplan (1979) collapses the excitement
and plateau phases into one, eliminates the resolution phase, and adds a phase
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Pubic bone
Uterus elevates
Bladder
Clitoral hood
Clitoris
Urethra
Labia minora
Vaginal lubrication
appears
Labia majora
Clitoris engorges
with blood
Labia minora swell
Anus
Labia majora swell
Unaroused
Excitement
Clitoral shaft
and glans swell;
glans retracts
beneath hood
Uterus elevates
further
Labia minora
deepen in color
and enlarge
Upper part of
vagina expands
Labia majora
separate from
the vaginal
opening
Vaginal wall forms
orgasmic platform
Color of labia
deepens
Late Excitement or Plateau
Clitoris withdraws
under clitoral hood
Bartholin’s
glands may
secrete a small
amount of fluid
Excitement
Contractions
in uterus
Clitoris remains
retracted under
hood
Rhythmic
contractions
in vagina
Orgasmic
platform
contracts
Rectal sphincter
contracts
Anal sphincter
contracts
Orgasm
Orgasm
Uterus lowers
Seminal pool
Orgasmic platform
disappears
Resolution
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Vagina returns
to normal
• FIGURE 3.9
Clitoris returns
to unaroused position
Masters and Johnson Stages of
Female Sexual Response (internal,
left; and external, right)
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TABLE 3.3
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Models of the Sexual Response Cycle
Psychological/Physiological Process
Name of Phase
People make a conscious decision to have sex even
if there might not be emotional or physical desire.
Willingness
(Loulan)
Some form of thought, fantasy, or erotic feeling causes
individuals to seek sexual gratification. (An inability to
become sexually aroused may be due to a lack of
desire, although some people have reported that they
acquire sexual desire after being sexually aroused.)
Desire
(Kaplan, Loulan)
Physical and/or psychological stimulation produces
characteristic physical changes. In men, increased amounts
of blood flow to the genitals produce erection of the penis;
the scrotal skin begins to smooth out, and the testicles
draw up toward the body. Later in this phase, the testes
increase slightly in size. In women, vaginal lubrication begins,
the upper vagina expands, the uterus is pulled upward,
and the clitoris becomes engorged. In both women and men,
the breasts enlarge slightly, and the nipples may become erect.
Both men and women experience increasing muscular contractions.
Excitement
(Masters/Johnson,
Loulan)
Excitement
(Kaplan)
Sexual tension levels off. In men, the testes swell and
continue to elevate. The head of the penis swells slightly
and may deepen in color. In women, the outer third of the
vagina swells, lubrication may slow down, and the clitoris
pulls back. Coloring and swelling of the labia increase.
In both men and women, muscular tension, breathing,
and heart rate increase.
Plateau
(Masters/Johnson)
Increased tension peaks and discharges, affecting the
whole body. Rhythmic muscular contractions affect the
uterus and outer vagina in women. In men, there are
contractions of the tubes that produce and carry semen,
the prostate gland, and the urethral bulb, resulting in the
expulsion of semen (ejaculation).
Orgasm
(Masters/Johnson,
Kaplan, and Loulan)
The body returns to its unaroused state. In some women,
this does not occur until after repeated orgasms.
Resolution
(Masters/Johnson)
Pleasure is one purpose of sexuality and can be defined
only by the individual. One can experience pleasure during
all or only some of the above stages, or one can leave out
any of the stages and still have pleasure.
Engorgement
(Loulan)
Pleasure
(Loulan)
to the beginning of the process. Kaplan’s tri-phasic model of sexual response
includes the desire, excitement, and orgasm phases. Though Masters and
Johnson’s and Kaplan’s are the most widely cited models used to describe the
phases of the sexual response cycle, they do little to acknowledge the affective
parts of human response. A third but much less known pattern is Loulan’s
sexual response model, which incorporates both the biological and affective
components into a six-stage cycle. Beyond any questions of similarities and
differences in the female and male sexual response cycle is the more significant
issue of variation in how individuals experience each phase. The diversity of
experiences can be described only by the individual. (These models are described
and compared in Table 3.3.)
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To help organize our thinking about the complexities of human behavior,
the dual control model provides a theoretical perspective of sexual response that
is based on brain function and the interaction between sexual excitation (responding with arousal to sexual stimuli) and sexual inhibition (inhibiting sexual
arousal) (Bancroft, Graham, Janssen, & Sanders, 2009). The authors of this
model argue that, though much research has been dedicated to understanding
sexual excitation, little research has been conducted on the inhibitory brain
mechanisms which provide an equally significant role in sexual arousal and
response. They purport that the adaptive role the inhibitory mechanism produces is relevant to our understanding of “normal” sexuality, individual variability, and problematic sexuality. The functions of the inhibitory response can
be found in the following circumstances: (1) When sexual activity in a specific
situation is potentially risky (as when you or your partner suspects an unintended
pregnancy could result); (2) when a nonsexual challenge occurs and sex needs
to be suppressed (as when a child calls out for help); (3) when excessive involvement in the pursuit of sexual pleasure distracts from other important functions
(as when someone is late for work because he or she is distracted by viewing
sexually explicit materials); (4) when social or environmental pressure results in
suppression of reproductive behavior (as when someone is so stressed during
finals week, he or she doesn’t feel like having sex); and (5) when the consequences of continued excessive sexual behavior potentially reduces possible conception (as when repeated ejaculations can result in lower sperm count).
A major finding of the dual control model is that it views excitation and
sexual inhibition as separate systems, as opposed to other models that view
these as two ends of a single dimension. Additional findings from this model
include the following:
■ Though most people fall in the moderate range on propensities toward
■
■
■
■
■
sexual excitation and sexual inhibition, there is great variability from one
person to the next.
Men, on average, score higher on excitation and lower on inhibition
than women.
Gay men, on average, score higher on excitation and lower on inhibition
than straight men.
Bisexual women, on average, score higher on excitation than lesbian and
straight women.
Excitation lessens with age for men and women; however, inhibition is
not age-related in women but is somewhat age-related in men.
The relation between negative mood and sexuality is best predicted by
inhibition scores in men, but by excitation scores in women.
The dual control model postulates that individuals who have a low propensity for sexual excitation or a high propensity for sexual inhibition are more
likely to experience difficulties related to sexual response or sexual interest.
Furthermore, those who have a high propensity for sexual excitation or low
propensity for sexual inhibition are more likely to engage in problematic sexuality such as high-risk sexual behaviors, for example, not using a condom.
Because the focus is on sexual arousal, there remain questions about if and how
this model might apply to orgasm. As long as researchers see it as a model
rather than as a description of reality, then the model and questionnaire used
for investigating it can be improved.
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Desire: Mind or Matter?
Desire is the psychological component of sexual arousal. Although we can experience desire without becoming aroused, and in some cases become aroused
without feeling desire, some form of erotic thought or feeling is usually involved
in our sexual behavior. The physical manifestations of sexual arousal involve a
complex interaction of thoughts and feelings, sensory organs, neural responses,
and hormonal reactions involving various parts of the body, including the
nucleus accumbens, cerebellum, and hypothalamus of the brain, the nervous
system, the circulatory system, and the endocrine glands—as well as the genitals.
A meta-study, which combined the results of several studies, of men’s and
women’s sexual arousal patterns found that in women, lubrication was only
one of the physiological changes that occurred when they were sexually aroused,
and not a necessary condition for women to report that they were sexually
aroused (Chivers, Seto, Lalumière, & Grimbos, 2010). Much of the science
behind sexuality was designed around a very linear model: First, there’s desire,
then there’s arousal, followed by orgasms, then snuggling. For most women,
this process is more circular, whereby sexuality is about intimacy, relationships,
and wanting to cuddle first and feel close to someone. It’s also about how
women feel about themselves. If they do not feel desirable or comfortable with
their bodies, it’s likely that they will not be able to relax and enjoy the sexual
interchange.
Among men who have trouble getting erect, genital engorgement is aided
by drugs such as Viagra because the pills target genital capillaries. (See Chapter 14
for more information about erection-enhancing drugs.) Thus, the medications
may enhance male desire by granting men a feeling of power and control, but
not necessarily desire or wanting. For some men, desire is not an issue. In
women, the primary difficulty appears to be in the mind, not the body (Brotto,
Heiman & Tolman, 2009). Therefore, experimental attempts to use penileenhancing drugs to treat women who complain of low sexual desire have proven
ineffective (Bergner, 2010). In both cases, then, the physiological effects of the
drugs have proven irrelevant.
Some desire is necessary to keep life in
“ motion.
—Samuel Johnson
(1709–1784)
The Neural System and Sexual Stimuli The brain is crucial to sexual response
and is currently a focus of research to understanding how we respond to sexual
stimulation. Through the neural system, the brain receives stimuli from the five
senses plus one: sight, smell, touch, hearing, taste, and the imagination.
The Brain The brain, of course, plays a major role in all of our body’s functions. Nowhere is its role more apparent than in our sexual functioning. The
relationship between our thoughts and feelings and our actual behavior is not
well understood (and what is known would require a course in neurophysiology
to satisfactorily explain it). Relational factors and cultural influences, as well as
expectations, fantasies, hopes, and fears, combine with sensory inputs and neurotransmitters (chemicals that transmit messages in the nervous system) to
bring us to where we are ready, willing, and able to be sexual. Even then,
potentially erotic messages may be short-circuited by the brain itself, which can
inhibit as well as incite sexual responses. It is not known how the inhibitory
mechanism works, but negative conditioning and emotions will prevent the
brain from sending messages to the genitals. In fact, the reason moderate
amounts of alcohol and marijuana appear to enhance sexuality is that they
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Women might be able to fake orgasms.
“ But men can fake whole relationships.
—Sharon Stone
(1958–)
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reduce the control mechanisms of the brain that act as inhibitors. Conversely,
women who feel persistent sexual arousal and no relief from orgasm reveal
unusually high activation in regions of the brain that respond to genital stimulation (Komisaruk et al., 2010). (See Chapter 14 for a discussion of persistent
sexual arousal syndrome.)
Anatomically speaking, the part of the body that appears to be involved
most in sexual behaviors of both men and women is the vast highway of nerves
called the vagus nerve network that stretches to all the major organs, including
the brain. Using MRI scans to map the brain, researchers have found increases
in brain activity during sexual arousal (Holstege et al., 2003; Komisaruk et al.,
2010). Since specific parts of the brain send their sensory signals via specific
nerves, the different quality of orgasms that result from clitoral or anal stimulation, for example, is divided among the different genital sensory nerves.
As many of us know, the early stages of a new romantic relationship are
characterized by intense feelings of euphoria, well-being, and preoccupation
with the romantic partner. This was observed in one study in which college
students were shown photos of their beloved intermixed with photos of an
equally attractive acquaintance (Younger, Aron, Parke, Chatterjee, & Mackey,
2010). Induced with pain during the experiment, students reported their pain
was less severe when they were looking at photos of their new love. The test
results suggest the chemicals the body releases in the early stages of love—
otherwise referred to as endogeneous opioids—work on the spinal cord to block
the pain message from getting to the brain. MRI scans showed that, indeed,
the areas of the brain activated by intense love are the same areas targeted by
pain-relieving drugs.
The Senses An attractive person (sight), a body fragrance or odor (smell), a
lick or kiss (taste), a loving caress (touch), and erotic whispers (hearing) are all
capable of sending sexual signals to the brain. Preferences for each of these
sensory inputs are both biological and learned and are very individualized.
Many of the connections we experience between sensory data and emotional
responses are probably products of the limbic system, or those structures of
the brain that are associated with emotions and feelings and involved in sexual
arousal. Some sensory inputs may evoke sexual arousal without a lot of conscious thought or emotion. Certain areas of the skin, called erogenous zones,
are highly sensitive to touch. These areas may include the genitals, breasts,
mouth, ears, neck, inner thighs, and buttocks; erotic associations with these
areas vary from culture to culture and from individual to individual. Our olfactory sense (smell) may bring us sexual messages below the level of our conscious
awareness. Scientists have isolated chemical substances, called pheromones, that
are secreted into the air by many kinds of animals, including humans, ants,
moths, pigs, deer, dogs, and monkeys. One function of pheromones, in animals
at least, appears to be to arouse the libido.
Sensory inputs, such as the sight,
touch, or smell of someone we
love or the sound of his or her
voice, may evoke desire and
sexual arousal.
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Hormones The libido in both men and women is biologically influenced by
the hormone testosterone. In men, testosterone is produced mainly in the
testes; in women, it is produced in the adrenal glands and the ovaries. Growing
evidence suggests that testosterone may play an important role in the maintenance of women’s bodies (Davis, Davison, Donath, & Bell, 2005). Although
it does not play a large part in a woman’s hormonal makeup, it is present in
the blood vessels, brain, skin, bone, and vagina. Testosterone is believed to
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contribute to bone density, blood flow, hair growth, energy and strength, and
libido.
Although women produce much less testosterone than men, this does not
mean that they have less sexual interest; apparently, women are much more
sensitive than men to testosterone’s effects. Though testosterone decreases in
women as they age, the ovaries manufacture it throughout life. Symptoms
produced by the decrease of testosterone can be similar to those related to
estrogen loss, including fatigue, vaginal dryness, and bone loss. Signs specific
to testosterone deficiency are associated with reduced sexual interest and responsiveness in men. The effects of such hormonal changes in women are less
predictable (Bancroft, 2009). In spite of widespread claims of testosterone’s
effect in treating low sex desire in women, in December 2004, the Food and
Drug Administration voted against approval of a testosterone patch, citing
concerns about the safety of long-term use of the patch and use by groups that
have not been adequately studied. More recently, the balance of evidence seems
to show that testosterone replacement therapy for surgically and naturally
menopausal women has, if used properly under medical supervision, a more
positive effect than a negative one on women (Panzer & Guay, 2009). Though
sexual problems, including low libido and/or sexual dissatisfaction, may have
physiological causes, they may also be caused by relationship issues, work
fatigue, past experiences, or financial problems. It is necessary to look beyond
medical solutions when assisting women who have the courage to confront
their sexual dissatisfaction. (Testosterone replacement therapy is discussed in
Chapter 7.)
Estrogen also plays a role in sexual functioning, though its effects on sexual
desire are not completely understood. In addition to protecting the bones and
heart, in women estrogen helps to maintain the vaginal lining and lubrication,
which can make sex more pleasurable. Men also produce small amounts of
estrogen, which facilitates the maturation of sperm and maintains bone density.
Too much estrogen, however, can cause erection difficulties. Like testosterone
replacement, some doctors are also promoting estrogens and bioidentical or
natural estrogen supplements to treat conditions caused by estrogen deficiency.
The most significant push is aimed at menopausal women. Because no risk-free
hormone has ever been identified, claims that human estrogens will protect
against cardiovascular effects and other maladies are misleading. While a number of estrogens are effective treatments for hot flashes and vaginal dryness, any
health-promotion claims for these drugs are clearly wrong. Shown to be somewhat effective in relieving symptoms associated with some female sexual function difficulties is a botanical called Zestra (Ferguson, Hosmane, & Heiman,
2010). By increasing blood flow and nerve conduction, this product was found
to significantly increase clitoral and vaginal warmth, increase arousal, and
improve sexual pleasure.
Oxytocin is a hormone more commonly associated with contractions during
labor and with breastfeeding. It is also increased by nipple stimulation in men
and women. This neurotransmitter, which has also been linked to bonding, is
released in variable amounts in men and women during orgasm and remains
raised for at least 5 minutes after orgasm (Carmichael et al., 1987). It helps us
feel connected and promotes touch, affection, and relaxation. Interestingly, oxytocin is important in stimulating the release of all the other sex hormones and,
since it peaks during orgasm, it may be responsible for the desire to touch or
cuddle after orgasm occurs (Chia & Abrams, 2005).
The age of a woman doesn’t mean a
“ thing. The best tunes are played on
the oldest fiddles.
—Ralph Waldo Emerson
(1803–1882)
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think
about it
The Role of Orgasm
Many of us measure both our sexuality and ourselves in
terms of orgasm: Did we have one? Did our partner have one?
If so, was it good? Did we have simultaneous orgasms? When we
measure our sexuality by orgasm, however, we discount
activities that do not necessarily lead to orgasm, such as touching, caressing, and kissing. We discount erotic pleasure as an end
in itself. Our culture tends to identify sexual activity with sexual
intercourse, and the end of sexual intercourse is literally orgasm
(especially male orgasm).
An Anthropological and Evolutionary Perspective
A fundamental, biological fact about orgasm is that male
orgasm and ejaculation are required for reproduction, whereas
the female orgasm is not. The male orgasm is universal in both
animal and human species, but sociobiologists and anthropologists have found immense variation in the experience of female
orgasm. Anthropologists such as Margaret Mead (1975) found
that some societies, such as the Mundugumor, emphasize the
female orgasm but that it is virtually nonexistent in other
societies, such as the Arapesh.
In our culture, women most consistently experience orgasm
through a combination of vaginal intercourse and manual and
oral stimulation of the clitoris. In cultures that cultivate female
orgasm, according to sociobiologist Donald Symons (1979),
there is, in addition to an absence of sexual repression, an emphasis on men’s skill in arousing women. In our own culture,
among men who consider themselves (and are considered)
“good lovers,” great emphasis is placed on their abilities to
arouse their partners and bring them to orgasm. These skills
include not only penile penetration but also, often more
importantly, clitoral or G-spot stimulation. This, of course, is
based on the sexual script that men are to “give orgasms to
women,” a message that places pressure on men and that tells
women they are not responsible for their own sexual response.
According to this script, the woman is “erotically dependent” on
the man. The woman can, of course, also stimulate her own
clitoris to experience orgasm.
Because it is closely tied to reproduction, evolutionary
scientists have never had difficulty explaining the male orgasm;
it ensures reproduction. In the same vein, scientists have for
decades insisted on finding an evolutionary function for female
orgasm but have not been as successful. Possibly, one effect
of orgasm is to increase a suction in the uterus to draw up
ejaculated semen thereby increasing the retention of sperm
(Komisaruk et al., 2010). Since women can have sexual intercourse
and become pregnant without experiencing orgasm, perhaps
there is no evolutionary function for orgasm (Lloyd, 2005).
However, philosopher and professor Elisabeth Lloyd acknowledges, evolution does not dictate what is culturally important.
In reviewing 32 studies conducted over 74 years, Lloyd found
that when intercourse was unassisted—that is, not accompanied by stimulation of the clitoris—just one quarter of the
women studied experienced orgasms often or very often
and a full one third never did; the rest sometimes did and
sometimes didn’t.
The Tyranny of the Orgasm
Sociologist Philip Slater (1974) suggests that our preoccupation
with orgasm is an extension of the Protestant work ethic, in
which nothing is enjoyed for its own sake; everything is work,
In spite of what we do know about the importance of biological influences
on sexual desire and performance, when biological determinants or evolutionary
accounts are given undue weight and psychosocial forces are ignored or minimized, a medical model that negates the significance of culture, relationships,
and equality can emerge (Lloyd, 2007; Wood, Koch, & Mansfield, 2006).
“
Those who restrain desire do so because
theirs is weak enough to be restrained.
—William Blake
(1757–1827)
98
•
Chapter 3
Experiencing Sexual Arousal
For both males and females, physiological changes during sexual excitement
depend on two processes: vasocongestion and myotonia. Vasocongestion is the
concentration of blood in body tissues. For example, blood fills the genital
regions of both males and females, causing the penis to become erect and the
clitoris to swell. Myotonia is increased muscle tension accompanying the
approach of orgasm; upon orgasm, the body undergoes involuntary muscle
Female Sexual Anatomy, Physiology, and Response
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including sex. Thus, we “achieve” orgasm much as we achieve
success. Those who achieve orgasm are the “successful workers”
of sexual activity; those who do not are the “failures.”
As we look at our sexuality, we can see pressure to be successful lovers. Men talk of performance anxiety. We tend to
evaluate a woman’s sexual self-worth in terms of her being orgasmic (able to have orgasms). For men, the significant question about women’s sexuality has shifted from “Is she a virgin?”
to “Is she orgasmic?”
Pretending Orgasm
The idea that women “fake” orgasms is familiar, probably
because there is considerable pressure on them to do so.
What is less well-known is that some men also pretend orgasm. Research on pretending orgasm can provide interesting insights into sexual scripts and their functions and
meanings for both sexes (Muehlenhard & Shippee, 2009). Researchers and professors Muehlenhard and Shippee found
that 25% of men and 50% of women reported pretending orgasms, but that these rates were even higher for those who
had experienced penile-vaginal intercourse. Frequently
reported reasons for pretending orgasm (reported by both
sexes) were that orgasm was unlikely, they wanted sexual
activity to end, and they wanted to avoid negative consequences (hurting their partners’ feelings) and obtain positive
ones (pleasing their partners). Both men’s and women’s narratives suggested a common sexual script in which the woman
should orgasm first, ideally during intercourse, and when the
man orgasms, sex is over. Thus, the researchers conclude, “It
seems that much of people’s sexual behavior is guided by
their or their partners’ scripts and expectations—even if this
requires pretending.” Such questions are often asked by men
rather than women, and women tend to resent them. Part of
the pressure to pretend to have an orgasm is caused by these
questions. What is really being asked? If the woman enjoyed
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intercourse? If she thinks the man is a good lover? Or is the
question merely a signal that the lovemaking is over?
“Was It Good for You?”
A question often asked following intercourse is “Was it good for
you?” or its variation, “Did you come?”
While the question “Was it good for you?” may initiate a dialogue, the statement “Orgasm is good for us” acknowledges a
fact. Though it’s apparent that orgasm feels good, some of us
may not recognize that orgasm is indeed good for our health.
Sexual activity not only burns quite a few calories and boosts the
metabolism, it also improves immune function, helps you sleep
better, and relieves menstrual cramps and stress. In fact, substantial connections between women’s sexual satisfaction and all
three aspects of their well-being (relational, mental, and physical)
have been reported (Holmberg, Blair, & Phillips, 2010). Though we
don’t yet understand all of the benefits of sex and orgasm, there
is mounting evidence that the enjoyment we receive from sex
moderates our hormones and improves our emotional state.
Think Critically
1. How important is it that each partner experience
orgasm? What (if anything) would you say to a sexual
partner who never or rarely experiences one?
2. Do you believe there are differences in the amount of
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