861
CHAPTER TWENTY-TWO
Reproductive System
abdominal pain. These breakdown products also
stimulate formation of fibrous tissue (fibrosis),
which may encase the ovary and prevent ovula-
tion or obstruct the uterine tubes. Conception
becomes impossible.
Some women become infertile as a result
of infections, such as gonorrhea. Infections can
inF
ame and obstruct the uterine tubes or stimu-
late production of viscous mucus that can plug
the cervix and prevent entry of sperm.
The ±
rst step in ±
nding the right treatment
for a particular patient is to determine the cause
of the infertility. Table 22C describes diagnostic
tests that a woman having di²
culty conceiving
may undergo.
many follicles to release egg cells simultaneously,
resulting in multiple births if fertilization occurs.
Another cause of female infertility is
endo-
metriosis,
in which tissue resembling the inner
lining of the uterus (endometrium) grows in
the abdominal cavity. This may happen if small
pieces of the endometrium move up through the
uterine tubes during menses and implant in the
abdominal cavity. Here the tissue changes as it
would in the uterine lining during the reproduc-
tive cycle. However, when the tissue begins to
break down at the end of the cycle, it cannot be
expelled to the outside. Instead, material remains
in the abdominal cavity where it may irritate
the lining (peritoneum) and cause considerable
F
or one out of six couples, trying for par-
enthood is a time of increasing concern,
as pregnancy remains elusive. Infertility is
the inability to conceive after a year of trying. A
physical cause is found in 90% of cases, and 60%
of the time, the abnormality lies in the female’s
reproductive system. Some medical specialists
(reproductive endocrinologists) use the term
“subfertility” to distinguish individuals and cou-
ples who can conceive unaided, but for whom
this may take longer than usual.
One of the more common causes of female
infertility is hyposecretion of gonadotropic hor-
mones from the anterior pituitary gland, followed
by failure to ovulate (anovulation). This type of
anovulatory cycle can sometimes be detected
by testing the woman’s urine for
pregnanediol,
a
product of progesterone metabolism. The con-
centration of progesterone normally rises follow-
ing ovulation, so no increase in pregnanediol in
the urine during the latter part of the reproduc-
tive cycle suggests lack of ovulation.
³ertility specialists can treat absence of
ovulation due to too little secretion of gonad-
otropic hormones by administering hCG
(obtained from human placentas) or another
ovulation-stimulating biochemical, human
menopausal gonadotropin (hMG), which con-
tains LH and ³SH and is obtained from urine of
women past menopause. However, either hCG
or hMG may overstimulate the ovaries and cause
22.3
CLINICAL APPLICATION
Female Infertility
PRACTICE
51
Trace the events of the female reproductive cycle.
52
What e´
ect does progesterone have on the endometrium?
53
What causes menstrual F
ow?
54
What are some changes that may occur at menopause?
22.6
MAMMARY GLANDS
The
mammary glands
are accessory organs of the female
reproductive system specialized to secrete milk following
pregnancy.
Location of the Glands
The mammary glands are located in the subcutaneous tissue
of the anterior thorax within the hemispherical elevations
be accompanied by chills and sweating. Women may also
experience migraine headache, backache, and fatigue dur-
ing menopause. These vasomotor symptoms may result from
changes in the rhythmic secretion of GnRH by the hypothala-
mus in response to declining concentrations of sex hormones.
TABLE
22C
|
Tests to Assess Female Infertility
Test
What It Checks
Hormone levels
If ovulation occurs
Ultrasound
Placement and appearance of reproductive organs and structures
Postcoital test
Cervix examined soon after unprotected intercourse to see if mucus is thin
enough to allow sperm through
Endometrial biopsy
Small piece of uterine lining sampled and viewed under microscope to see
if it can support an embryo
Hysterosalpingogram
Dye injected into uterine tube and followed with scanner shows if tube is
clear or blocked
Laparoscopy
Small, lit optical device inserted near navel to detect scar tissue blocking
tubes, which ultrasound may miss
To minimize menopause symptoms, some women take hormone
replacement therapy (HRT), which consists of estrogen plus progestin
to lower the risk of developing endometrial cancer. A woman whose
uterus has been removed may take estrogen alone, called estrogen
replacement therapy (ERT). A doctor prescribes the therapy in any
of several forms, including rings, patches, pills, creams, and gels. The
lowest e´
ective dose is taken for the shortest possible time. HRT is not
advised for women who have a history of or high risk of abnormal blood
clotting, heart disease, stroke, breast cancer, or gallbladder disease.
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