The most common causes of female infertility can be attributed to the following: -
This condition usually results from inflammation of the fallopian tube (salpingitis).
Chlamydia is the most frequent cause.
Tubal inflammation may go unnoticed or cause pain and fever. Tubal damage with scarring
is the major risk factor of a pregnancy in which the fertilized egg is unable to
make its way through the fallopian tube to implant in the uterus (ectopic pregnancy).
One episode of tubal infection may cause fertility difficulties in about 12% of
couples and by the third episode more than 50% of women have blocked tubes. The
risk of ectopic pregnancy increases with each occurrence of tubal infection.
Endometriosis occurs when the tissue that makes up the lining of the uterus grows
outside the uterus. This tissue most commonly is implanted on the ovaries or the
lining of the abdomen near the uterus, fallopian tubes and ovaries. These implants
respond to the hormonal cycle and grow, shed and bleed in sync with the lining of
the uterus each month, which can lead to scarring and inflammation. Pelvic pain
and infertility are common in women with endometriosis.
Infertility in endometriosis also may be due to:
Ovarian cysts (endometriomas). Ovarian cysts may indicate advanced endometriosis
and often are associated with reduced fertility. Endometriomas can be treated with
surgery.
Scar tissue
Endometriosis may cause rigid webs of scar tissue between the uterus, ovaries and
fallopian tubes. This may prevent the transfer of the egg to the fallopian tube.
Certain factors
Certain factors released from the endometriotic tissue prevent sperm and egg interaction
or destroy them both or sometimes just prevent the fertilized egg from attaching
to the uterine lining.
About 25 percent of female infertility is caused by ovulation disorders. Disruption
in the part of the brain that regulates ovulation (hypothalamic-pituitary axis)
can cause deficiencies in luteinising hormone (LH) and follicle-stimulating hormone
(FSH). Even slight irregularities in the hormone system can affect ovulation.
Specific causes of hypothalamic-pituitary disorders include:
- Direct injury to the hypothalamus or pituitary gland
- Pituitary Tumors
- Excessive Exercise
- Anorexia Nervosa
The hormone prolactin stimulates breast milk production. High levels in women who
aren't pregnant or nursing may affect ovulation. An elevation in prolactin levels
may also indicate the presence of a pituitary tumor. Some drugs can elevate levels
of prolactin. Milk flow not related to pregnancy or nursing (galactorrhoea) can
be a sign of high prolactin.
An increase in androgen hormone production causes PCOS. In women with increased
body mass, elevated androgen production may come from stimulation by higher levels
of insulin. In lean women, the elevated levels of androgen may be stimulated by
a higher ratio of luteinising hormone (LH). Lack of menstruation (amenorrhea) or
infrequent menses (Oligomenorrhoea) are common symptoms in women with PCOS.
In PCOS, increased androgen production prevents the follicles of the ovaries from
producing a mature egg. Small follicles that start to grow but can't mature to ovulation
remain within the ovary. A persistent lack of ovulation may lead to mild enlargement
of the ovaries. Without ovulation, the hormone progesterone isn't produced and estrogen
levels remain constant. Elevated levels of androgen may cause increased dark or
thick hair on the chin, upper lip or lower abdomen as well as acne and oily skin.
Early menopause is the absence of menstruation and the early depletion of ovarian
follicles before age 35. Although the cause is often unknown, certain conditions
are associated with early menopause, including:
Autoimmune Disease
The body produces antibodies to attack its own tissue, in this case the ovary. This
may be associated with hypothyroidism (too little thyroid hormone).
Radiation or chemotherapy for the treatment of cancer
Tobacco smoking
Fibroids are benign tumors in the wall of the uterus and are common in women in
their 30s. Occasionally they may cause infertility by interfering with the contour
of the uterine cavity, blocking the fallopian tubes.
Pelvic adhesions are bands of scar tissue that bind organs after pelvic infection,
appendicitis, or abdominal or pelvic surgery. They may limit the functioning of
the ovaries and fallopian tubes and impair fertility. Scar tissue formation inside
the uterine cavity after a surgical procedure may result in a closed uterus and
ceased menstruation (Asherman's syndrome). This is most common following surgery
to control uterine bleeding after giving birth.
A number of other causes can lead to infertility in women:
Medications
Temporary infertility may occur with the use of certain medications. In most cases,
fertility is restored when the medication is stopped.
Thyroid problems
Disorders of the thyroid gland, either too much thyroid hormone (hyperthyroidism)
or too little (hypothyroidism), can interrupt the menstrual cycle and cause infertility.
Cancer and its treatment
Certain cancers - particularly female reproductive cancers - often severely impair
female fertility. Both radiation and chemotherapy may affect a woman's ability to
reproduce. Chemotherapy may impair reproductive function and fertility more severely
in men than in women.
Other medical conditions Medical conditions associated with delayed puberty
or amenorrhea, such as Cushing's disease, sickle cell disease, HIV/AIDS, kidney
disease and diabetes, can affect female fertility.