Chapter 4
Female Sexual
Anatomy & Physiology
Genital Self-Exam
• Increases sexual comfort
– Feeling familiar and comfortable with one’s
anatomy can enhance sexual experiences
• Monitor for changes related to health
concerns
– If you don’t know what “normal” looks like, you
can’t know if something seems abnormal and
requires medical attention.
The Vulva
• Vulva = all female external genital structures
– Includes hair, folds of skin, and urinary and vaginal
openings
– Appearance varies from person to person
The Vulva (cont.)
Fig. 4.1 The structures and variations of the vulva: (a) external structures.
Tour of the Vulva
Mons veneris (from Latin “mound of Venus”):
- Triangular mound over the pubic bone.
- Consists of pads of fatty tissue btwn. pubic bone and skin.
- Touch and pressure can be pleasurable due to numerous nerve endings.
- At puberty, becomes covered with hair
- Purpose of hair is to trap pheromones from vaginal secretions, adding to sensory
erotic pleasure.
Labia majora (outer lips):
- Extend downward from mons
veneris on each side of vulva.
- Like mons veneris, touch and
pressure can be pleasurable
due to numerous nerve endings.
Tour of the Vulva
Labia minora (inner lips):
- Located within outer lips and may protrude between them.
- Hairless folds of skin that join at the prepuce (clitoral hood) and
extend down past urinary and vaginal openings
- Contain sweat glands, blood vessels, and nerve endings.
- Vary considerably in size, shape, and color; become darker in
color during pregnancy.
Tour of the Vulva
Clitoris:
- Highly sensitive structure of the female
external genitals.
- Is the only organ in the human body
whose only function is pleasure.
- Consists of:
- glans
- shaft: has small spongy structures
that engorge with blood during
sexual arousal.
- internal crura (roots)
- Covered by clitoral hood
- Stimulation of clitoris is the most
common way that most women
achieve orgasm.
- External part of the clitoris has
about the same # of nerve
endings as the head of the penis.
Tour of the Vulva
Vestibule:
- Area inside labia minora.
- Urinary and vaginal openings are located within the vestibule.
Perineum:
- Area of skin between the
vaginal opening and the
anus
- Urinary and vaginal
openings are located within
the vestibule.
Female Genital Cutting
• Circumcision: cutting off the clitoral hood.
• Clitoridectomy: removal of the clitoris.
• Genital infibulation:
– Removal of the clitoris
– Labia are cut off
– Both sides of the vulva are stitched together
• Procedures done w/o anesthetics, disinfectants, or
sterile instruments
• Cultural tradition in >40 countries in Africa, the
Middle East, and Asia--clitoris is seen as male b/c it
gets erect; ensures marriageability of girls
• Serious gynecological and obstetric complications
result from infibulation
Underlying Structures of the Vulva
(Fig 4.2)
–Fill with blood during arousal,
causing vulva to swell and vagina
to increase in length.
–Similar in structure and function
to tissue in penis that engorges
during arousal, causing erection.
Secrete drop or two of
fluid just before orgasm.
Underlying Structures of the Vulva
more on Kegel
exercises in Chp. 5…
Fig. 4.3 The underlying muscles of the vulva. These muscles can be strengthened
using the Kegel exercises described in the text.
Internal Structures (cont.)
Fig. 4.4 Internal female sexual anatomy: front view of the internal organs. Parts of the
ovaries, uterus, and vagina are shown cut away.
Internal Structures (cont.)
Fig. 4.4 Internal female sexual anatomy: (a) cross-sectional side view of female
internal structures.
• Vagina
Internal Structures
– Approx. 3-5 in. long--can elongate during arousal, stretch
during childbirth, etc.
– 3 layers: mucous, muscle, fibrous
– Arousal and vaginal lubrication
• Vaginal tissue blood vessels become engorged, causing clear
fluid from the tissues to moisten the inside of the vaginal wall.
• lubrication changes () vaginal pH and increases pleasure
– Grafenberg (G) spot
• Anterior (front) wall of vagina
• Female equivalent of prostate gland
– Secretions & chemical balance
• Douching, feminine hygiene sprays, etc. are not only
unnecessary, they cause numerous health problems.
• Cervix
Internal Structures
– At the upper/back end of the vagina
– Leads into uterus
• Os: the small opening in the cervix that leads into
uterus
– Dilates to 10 cm opening during labor & birth
Internal Structures
• Uterus (or womb)
– Hollow, thick, pear-shaped organ
– 3 in. long, 2 in. wide in woman who has not had
a child.
– Walls consist of 3 layers
• External: perimetrium
• Middle: myometrium
– (stretching, contraction)
• Inner: endometrium
– (nourishes zygote, sheds each month if no fertilization
during menstruation)
Internal Structures
• Fallopian tubes
– Extend from uterus to each ovary (each tube about 4 in.)
– Lined with cilia to help move ovum along tube
– Outside end of each tube is shaped like a funnel, with
fringelike projections called fimbriae
• When egg leaves ovary, it’s drawn into fallopian tube by the
fimbriae.
Fertilization
– Ectopic pregnancy: when fertilized ovum implantsoccurs fairly
outside of the uterus (usually in the fallopian tube). close to ovary
• Can rupture the tube and cause uncontrolled bleeding
Internal Structures
• Ovaries
– Endocrine glands that produce ova (eggs) and sex
hormones.
– 3 types of hormones produced:
• Estrogens
• Progesterones
• Testosterone
– Ovulation: the maturation and release of an egg
from the ovary into the fallopian tube
• Up to 472,000 ova at birth
• Only about 400 will mature
Group activity: female A & P flashcards
One side: name of term
Other side: definition, function, location
TERMS:
Vulva
Mons veneris
Labia majora
Labia minora
Clitoris
Perineum
Vagina
Cervix
Uterus
Fallopian tubes
Ovaries
Discussion question: (4-A)
• What are some slang terms for female
genitalia and breasts? Keep track of how
many terms your group knows.
•
Are these terms positive or negative?
• Why do people tend to use “nicknames” for
parts of the female sexual anatomy? •
How might men and women become more
comfortable using correct terms for female
anatomy?
Menstruation
• Myths and negative attitudes
– In the U.S., girls used to be taught that menstruation was
dirty, something to be hidden.
• Advertisements for “feminine hygiene products” often capitalized
on these negative attitudes toward menstruation (see next slide)
– Some cultural attitudes toward menstruation are positive
• Association with transformation to adulthood, purification,
spirituality, connectedness with natural cycles.
– Today, even w/negative attitudes, most women associate
regular menstruation with health.
– Research has shown that women who have positive
attitudes and comfort w/menstruation are more likely to
be comfortable with their bodies and their sexuality.
Menstruation (cont.)
• Menarche (initial onset)
– age 11-15 (avg: about 12.5 yr)
– related to heredity, health,
– Age has decreased over time:
• Many reasons proposed,
environmental
pesticides, etc.),
altitude
including
estrogens (in
obesity, stress.
• Menstrual physiology
–
–
–
–
flow lasts from 2 to 6 days
volume varies (6 to 8 ounces)
duration varies (24 to 42 days)
menstrual synchrony: simultaneous menstrual cycles that sometimes
occur among women who live in close proximity.
Menstruation (cont.)
Fig. 4.7 Ovulation timing and cycle length. Regardless of the length of the cycle,
ovulation occurs approximately 14 days before menstruation.
Menstrual cycle: control by hormones
• hypothalamus releases GnRH that stimulates pituitary
• pituitary produces:
– Follicle-stimulating hormone (FSH):
• Estrogen production in ovaries
• Ovum maturation in follicles inside ovaries
– Luteinizing hormone (LH):
• Stimulates release of mature ovum
• Stimulates development of corpus luteum, the progesteronesecreting part of the follicle that remains after egg is released.
• Negative feedback mechanism
– Each hormone is secreted until the organ it acts upon is
stimulated--then that organ secretes a hormone that
reduces secretion of the first hormone.
Menstrual cycle: 3 phases
1) Menstrual phase: menstruation
-
Menstrual flow=endometrial tissue, blood, and mucus
-
 FSH: ovum (egg) matures inside follicle
Egg produces estrogen: causes endometrium to thicken a
little
 LH: causes ovulation (release of mature egg from follicle)
2) Proliferative phase: follicles mature, release ovum
-
3) Secretory phase: corpus luteum develops
-
Corpus luteum develops from follicle & secretes
progesterone
 progesterone: endometrium thickens & engorges w/blood &
nutrients in preparation for implantation of a fertilized egg
If there is no implantation, corpus luteum degenerates, and
estrogen & progesterone levels fall --> triggers menstruation.
Changes during
menstrual cycle
Gonadotropins (FSH, LH)
Changes in the ovary
Levels of estrogen &
progesterone
Changes in the
endometrium
Proliferative phase:
Changes to ovaries and uterus
• Follicle matures and releases ovum
• Uterine lining begins to thicken
Fig 4.6a
Secretory phase:
Changes to ovaries and uterus
Uterine lining
continues to thicken
• Development of corpus luteum from follicle
(corpus luteum degenerates if there’s no implantation of a
fertilized egg in the uterus)
• Uterine lining continues to thicken
Fig 4.6b
Menstrual phase:
Changes to ovaries and uterus
• Uterine endometrium is shed as menstrual flow
Fig 4.6c
Menstruation (cont.)
• Sexual activity and the menstrual cycle
• Menstrual cycle problems
– premenstrual syndrome:
• Premenstrual Dysphoric Disorder
– dysmenorrhea = painful menses
– amenorrhea = no menses
– toxic shock syndrome
– self-help for menstrual symptoms
Sexual activity and the
menstrual cycle
• Libido is typically maximal around ovulation, as
well as during menstruation
• There are no medical reasons to avoid sex
during menstruation
• Orgasm during menstruation can be beneficial-relieves, backache, cramping, etc.
Menstrual cycle problems
• Premenstrual syndrome (PMS) - catchall term
for a number of symptoms of physical discomfort
and emotional irritability 2-12 days before
menstruation
– PMDD (Premenstrual dysphoric disorder):
Premenstrual symptoms severe enough to significantly
affect a woman’s functioning
• Dysmenorrhea - pain or discomfort before or
during menstruation - Can include cramping,
backache, headache, nausea, fatigue
• Amenorrhea - absence of menstruation
– Can be caused by too little body fat (amenorrhea is
common in training athletes, women with anorexia nervosa)
Discussion question (4-B):
PART 1: What types of sexual activity
are acceptable during menstruation?
PART 2: Where did you learn about female
sexual anatomy and the menstrual cycle?
Was the information that you received
accurate and thorough?
Menopause
• Terms
– Peri-menopause: time before menopause,
when estrogen levels are decreasing
– Menopause: permanent cessation of
menstruation
• Average age is 51 (range: 30s to 60s)
Menopause (cont.)
• Symptoms vary from mild to strong (due
mostly to the decline in estrogen levels)
– hot flashes or warm spells from rapid dilation of
blood vessels (about 75% of women experience these)
– night sweats, interrupted sleep
– headaches, poor concentration
– depression, anxiety
– vaginal dryness, reduced libido
Hormone Therapy during
and after menopause
• Hormone therapy: the use of supplemental
hormones (estrogen, progesterone, testosterone)
– Benefits: (mostly estrogen) can reduce hot
flashes, night sweats, vaginal dryness, loss of
bone density and (mostly testosterone) increase
overall energy and sexual interest
– Problems: Increased risk of endometrial, ovarian,
and breast cancer; increased risk of blood clots,
cardiovascular disease (prog. HT)
Alternatives to Hormone Therapy
• Lifestyle factors
– Women who are sexually active have fewer
changes in vaginal tissues and lubrication.
– Exercise, avoiding caffeine, tobacco, alcohol,
and spicy foods can reduce hot flashes.
• Vitamins and herbs
– Calcium supplements, vitamin D, and weightbearing exercise can prevent osteoporosis.
– Vitamin E, herbs (e.g. dong quai or black
cohosh) can relieve symptoms such as hot
flashes.
Gynecological Health Concerns
• Urinary tract infections (UTIs)
– Usually due to bacteria that enter urethral opening.
– If infection spreads past bladder into kidneys, severe
illness can result.
– Treatable with antibiotics.
* Prevention:
 Wiping from front to back (from vulva to anus)
 Avoiding introducing bacteria from the rectum from into the
vagina during sexual activity
 Don’t wait to urinate--urinate as soon as you feel the urge
to avoid stretching the bladder
 Use water-soluble lubricants during sexual activity (not
petroleum jelly)
 Urinate after intercourse.
Gynecological Health Concerns (cont).
• Vaginal infections (aka vaginitis)
– Include yeast infections, bacterial infections, etc.
(more in Chp. 17)
– Some factors that increase susceptibility to vaginitis:
•
•
•
•
•
•
•
•
•
Diabetes
Antibiotic use
Stress
Diet high in simple carbohydrates
Intercourse w/o adequate lubrication
Hormonal changes due to pregnancy or birth control pills
Wearing nylon underwear or panty hose (trap heat and moisture)
Douching
Unprotected sex (STDs can cause vaginitis)
Gynecological Health Concerns (cont).
• Cysts
– Fluid-filled sac that sometimes grow on the ovary
– Fairly common, usually resolve on their own and are
unnoticeable
– Need to be monitored if they become painful
• Endometriosis
– Condition in which uterine endometrial tissue grows on
various parts of the pelvic cavity.
– Cause pelvic pain, often quite severe
– Can cause infertility
• Self-exams & vaginal health care
– The greater awareness a woman has about her body, the
better able she will be to diagnose problems.
The Pap Smear
• To screen for cervical cancer.
• Cells are taken from the cervix
and examined under the
microscope
• Since widespread use of Pap
smears began in 1950s, the
death rate of cervical cancer
has decreased dramatically b/c if cancer is found, it
is usually at a very early stage.
normal
dysplasia
cervical cancer
Surgical removal of the uterus or ovaries
• Hysterectomy: surgical removal of the uterus.
• Oophorectomy: surgical removal of the ovaries
• Can be necessary due to bleeding disorders, pelvic
infections, fibroids, cancer.
• Most frequently performed operation in U.S.--1/3 of
women will have a hysterectomy by age 65.
– more frequently performed on low income, less educated
women
• Can decrease sexual responsiveness due to
hormonal changes, loss of nerves in the pelvis, loss
of ability to have uterine contractions.
• There are some alternatives to surgery--women
should be fully informed about all options.
The Breast
• Mammary glands produce milk
– fatty tissue determines size
– There is little variation among women in amount of
glandular tissue present
• Therefore, amount of milk for breastfeeding doesn’t correlate with
breast size.
• Areola is darker area
• Nipple is in center of areola
– Has many nerve endings & has openings for milk.
• Breasts are secondary sex characteristics
– Physical characteristics other than genitals that indicate
sexual maturity (such as body hair, breasts, and deepened voice).
The Breast (cont.)
Fig. 4.8 Cross-section front and side views of the female breast.
Breasts come in lots of shapes and sizes
• Media/porn, etc. has distorted our idea of what a
“normal” breast looks like
• Some normal breasts: (from http://www.007b.com/breast_gallery.php)
Breast cancer screening
• Breast exams: early detection is best b/c
treatments work better on early stage cancers
– self-exam following menstruation
– routine healthcare provider exams
Breast cancer screening, (cont.)
• Mammography: X-ray of the breast
– Can detect breast lump before it can be felt manually.
– Recommended yearly for women over 50
– Sometimes recommended for women between 40-50,
though mammograms are less effective in women
under 50 b/c the breast tissue is more dense.
– Can miss tumors-• better screening methods are needed.
Breast health
• Breast lumps: 3 types
– cysts (fluid-filled sacs, benign)
– fibroadenomas (solid, round, benign tumors)
– malignant tumor (tumor made up of cancer cells)
• Breast cancer
– Incidence: 1 in 9 women in North America; 190,000 new
diagnoses each year.
– Kills 40,000 women in U.S. each year and 370,000
women worldwide each year.
– In North America, one woman dies of breast cancer
approximately every 12 minutes.
Breast cancer
• Early detection increases survival b/c cancer
is usually found at an earlier stage.
• The 5-year survival rate is lower for minority
women than for white women, most likely due
to differences in access to preventive health
care.
Stage of cancer
Percentage of cancer
diagnosed at this stage
Survival Rate
at 5 years (%)
Local (confined to breast)
60
98
Regional (spread to lymph nodes)
31
76
Distant (spread to other organs)
6
16
Breast cancer: risk factors
• Risk rises with age
• Growing evidence indicates that synthetic chemicals
found in plastics, pesticides, detergents, and
cosmetics can increase the risk of breast cancer
• Cosmetics and personal care products are not
tested by the Food and Drug Administration (FDA)
because they are not foods and are not drugs
– Nonetheless, chemicals in these products can penetrate
our skin and our bodies.
• To check your personal care products and, if
necessary, look for safer alternatives, go to:
www.cosmeticsdatabase.com
Breast cancer treatment
• Surgery
– Mastectomy: surgical removal of all or most of
the breast
– Lumpectomy: removal of part of the breast
containing the tumor and some surrounding
tissue.
• Chemotherapy and/or radiation
– Kills rapidly dividing cells (tumor cells generally
divide more than normal cells)
Breast cancer activism
• 3 local groups committed
to increasing awareness of
breast cancer and
advocating for breast
cancer prevention.
– Breast Cancer Fund (S.F.)
– Breast Cancer Action (S.F.)
– Women’s Cancer Resource
Center (Berkeley)
• Resource library, supportgroups
Discussion question: (4-C)
If you or your partner had a mastectomy
(removal of a breast), how do you think this
would affect your sexual feelings toward
yourself/your partner? What would the
effects be if you or your partner had a
hysterectomy (removal of uterus)