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U N I T 1 1
Genitourinary and Reproductive Function
Menstrual Disorders
Between menarche (i.e., first menstrual bleeding) and
menopause (i.e., cessation of menstruation), the female
reproductive system undergoes cyclic changes called
the
menstrual cycle
. This includes the maturation and
release of oocytes from the ovary during ovulation and
periodic vaginal bleeding resulting from the shedding of
the endometrial lining. The menstrual cycle produces
changes in the breasts, uterus, skin, ovaries, and perhaps
other unidentified tissues.
Dysfunctional Menstrual Cycles
Dysfunctional menstrual cycles may take many forms,
including dysfunctional bleeding, and
amenorrhea
(absence of menstruation) is failure to menstruate,
hypomenorrhea
(scanty menstruation),
oligomenor-
rhea
(infrequent menstruation, periods more than 35
days apart),
polymenorrhea
(frequent menstruation,
periods <21 days apart),
menorrhagia
(excessive men-
struation), or
metrorrhagia
(bleeding between peri-
ods).
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Menometrorrhagia
is heavy bleeding during and
between menstrual periods.
Although unexplained bleeding can occur because of
pregnancy, spontaneous abortion, neoplasms, or other
reasons, the frequent cause in the nonpregnant woman
is a condition commonly called
dysfunctional bleed-
ing
. Dysfunctional bleeding is related to alterations in
the hormones that support normal cyclic endometrial
changes. Estrogen deprivation causes retrogression of
a previously built-up endometrium and bleeding. Such
bleeding often is irregular in amount and duration,
with the flow varying with the time and degree of estro-
gen stimulation and with the degree of estrogen with-
drawal.
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A lack of progesterone can cause abnormal
menstrual bleeding. In its absence, estrogen induces
development of a much thicker endometrial layer with a
richer blood supply.
Periodic bleeding episodes alternating with amenor-
rhea are caused by variations in the number of function-
ing ovarian follicles present. When too many follicles
are present and active, high levels of estrogen develop,
causing the endometrium to proliferate for weeks or even
months. In time, either of two events occurs that lead to
an estrogen deficiency and bleeding: several follicles may
SUMMARY CONCEPTS
■■
The female external genitalia are affected by
disorders that affect skin on other parts of the
body. Bartholin cysts, which are the result of
occluded ducts in Bartholin glands, are often
painful and can become infected. Vulvodynia
is a chronic vulvar pain syndrome with several
classifications and variable treatment results.
Cancer of the vulva, is an uncommon malignant
neoplasm, which accounts for 3% to 5% of all
genital cancers in women.
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The normal vaginal ecology depends on a
delicate balance of hormones and bacterial
flora. Vaginitis or inflammation of the vagina is
characterized by vaginal discharge and burning,
itching, redness, and swelling of vaginal tissues.
It may be caused by chemical irritants, foreign
bodies, and infectious agents. Primary cancers
of the vagina are uncommon, accounting for
1% of all cancers of the female reproductive
system.
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Disorders of the cervix and uterus include
inflammatory conditions such as cervicitis and
endometritis. Endometriosis is a condition in
which functional endometrial tissue is found in
ectopic sites outside the uterus. Cervical cancer is
caused by HPV and arises from precursor lesions
that can be detected on Pap smear cytology, and
if detected early, is the most easily cured of all
the cancers of the female reproductive system.
Endometrial cancer is the most common cancer
of the female pelvis. Leiomyomas are benign
neoplasms of the uterine wall.
■■
Pelvic inflammatory disease (PID) is an
inflammation of the upper reproductive tract that
involves the uterus (endometritis), fallopian tubes
(salpingitis), or ovaries (oophoritis).
■■
Disorders of uterine support result from weakness
and relaxation of the pelvic floor muscles.
Cystocele and rectocele involve herniation of
the bladder or rectum into the vagina. Uterine
prolapse occurs when the uterus bulges into
the vagina.
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Disorders of the ovaries include cystic disorders,
polycystic ovary syndrome (PCOS), and
cancer of the ovary. Functional cysts usually
are asymptomatic unless there is substantial
enlargement or bleeding into the cyst or the cyst
becomes twisted or ruptures. Polycystic ovary
syndrome is a disorder characterized by various
degrees of hirsutism, obesity, and infertility,
and often is associated with hyperinsulinemia
and insulin resistance. Cancer of the ovary is
the second most common female genitourinary
cancer and the most deadly. A family history of
cancer, particularly breast and ovarian cancer,
and nulliparity increase the risk of developing
ovarian cancer, whereas oral contraceptive use,
pregnancy, and lactation decrease the risk.
