Female Infertility

Infertility is the inability of a sexually active couple, not using birth control, to get pregnant after one year of trying. About one quarter of female infertility is caused by a problem with ovulation. Normally, each month an egg matures within its own follicle (a sort of bubble) in the ovary and is released into the fallopian tube. This process of ovulation is the fertile time of the menstrual cycle.

Reasons for infertility
Lack of ovulation or infrequent ovulation:  Absent or irregular ovulation is a common cause of infertility, and can be caused by:

• polycystic ovary syndrome (PCOS)
• hypothalamic amenorrhea
• problems that cause the pituitary to release too much prolactin, a hormone that affects estrogen levels
• primary ovarian insufficiency

Age: There is a gradual decrease in egg quantity and quality beginning when a woman is in her mid 30s, or about 10 years before menopause.

Other hormone-related conditions: An overactive or underactive thyroid gland, diabetes, obesity, and, occasionally, Cushing’s syndrome (a disorder of the adrenal glands) can affect fertility. 

Other causes of infertility include tubal blockages, endometriosis, and male factor infertility.

Treatment of infertility
Infertility due to ovulation problems is treated with fertility drugs. These drugs, in general, work like natural hormones, such as FSH and LH, to bring about ovulation. Some commonly used fertility drugs are:

• Clomiphene. This oral medication causes the pituitary gland to release more FSH and LH.
• Gonadotropin therapy. These injected medications contain either FSH or both FSH and LH. These drugs stimulate the ovaries to develop egg-containing follicles. Most women need FSH only, but women with hypothalamic amenorrhea need both LH and FSH.
• Human chorionic gonadotropin (hCG). Used in combination with clomiphene and gonadotropin therapy, this drug, which is also given by injection, stimulates the follicle to release its egg (i.e., to ovulate).
• Bromocriptine and cabergoline. These oral medications are used to treat infertility caused by the body’s production of too much prolactin. Too much prolactin causes menstrual abnormalities.

Polycystic ovary syndrome (PCOS) and infertility
PCOS is a leading cause of infertility in women (for a detailed discussion, see our Polycystic Ovary Syndrome overview). Although not all women with PCOS have all these features, common signs and symptoms include:

• irregular menstrual cycles
• excess hair growth on the face and body
• infertility (due primarily to lack of ovulation)
• excess weight (especially at the waist)

On ultrasound, the ovaries appear to have a ring of small cysts. These are painless and do not become large cysts.

Normally, a woman’s ovaries and adrenals produce small amounts of male hormones (androgens), but women with PCOS have increased androgen levels. Higher levels of androgens lead to an imbalance in the hormones that regulate ovulation and normal egg development. Obesity, which is common in women with PCOS, contributes to infertility. Thus, weight loss, if needed, and treatment for PCOS with medications can restore ovulation.

Primary ovarian insufficiency (POI) and infertility
POI (previously known as premature ovarian failure, or POF), occurs when the ovaries stop working normally before a woman turns age 40. When this happens, women don’t ovulate on a regular basis or produce normal amounts of estrogen. The most common signs of POI are irregular or missed periods, along with hot flashes. Other symptoms may include:

• night sweats
• vaginal dryness
• irritability
• difficulty concentrating

In most cases, the cause of POI is unknown. It is sometimes linked to genetic disorders such as Turner syndrome and Fragile X syndrome, conditions that are due to changes to the X chromosome. The risk of developing POI is greater in women with a family history of the disorder.

Although some women with POI become pregnant, the chance of success is very low. Research is ongoing to identify treatments for restoring fertility in women with POI. Hormone therapy may be used to relieve menopause symptoms (such as hot flashes, night sweats, vaginal dryness) or to prevent osteoporosis (brittle bones).