Infertility

Infertility is far more common than most people think. According to research, one in eight couples—about 12 percent of the reproductive-age population—experience fertility problems and have difficulty achieving pregnancy.

The truth is that hundreds of variables must coincide precisely for conception to occur and for a woman's body to successfully maintain a pregnancy for nine months. A healthy, fertile 30-year-old woman who has regular unprotected intercourse has about a 20 percent chance of conception during each menstrual cycle. Once she reaches age 40, the odds drop to about 5 percent each cycle.

There is no "typical" infertile patient. Lack of ovulation and sperm deficiencies are the most common infertility problems.

Ovulation is a complicated communication process between the hormones in a woman's brain and the eggs and hormones in her ovaries. To understand ovulation problems related to infertility, you must first understand ovulation. As your menstrual cycle begins (day one of your period), your estrogen levels are low. Your hypothalamus (the area of your brain responsible for maintaining hormone levels) tells your pituitary gland to start producing a hormone called follicle stimulating hormone (FSH). The FSH triggers eggs that are ready to start developing to grow. One of these egg follicles will develop into the dominant mature egg destined to ovulate, and the others degenerate.

Follicles produce estrogen, and when the estrogen levels reach a certain threshold, the egg is mature and ready to be released. The pituitary gland then releases a hormone called luteinizing hormone (LH) that causes the egg to mature and be released from the ovary wall and begin its 48- to 72-hour or so journey through the fallopian tube.

Ovulation problems can occur due to a number of factors:

• The ovaries may no longer contain eggs
• Eggs are present in the ovary but ovulation is disrupted because of a breakdown in the hormonal communication cycle

Age is also a major factor in a woman's fertility. After age 35, a woman's fertility rapidly declines. By age 43, there are fewer normal eggs remaining in her ovary, and she is less likely to conceive.

The quality of a woman's eggs is critical to her chances of becoming pregnant. If a woman is having trouble conceiving, she may have an ovarian reserve test. If it indicates few high-quality eggs or a very low probability of conception, her physician may recommend using donor eggs.

While an older woman is more likely to have poor egg quality than a younger one, the condition can also affect younger women. Each year, about 20,000 in vitro fertilization (IVF) cycles include the use of donor eggs. Less common identifiable fertility problems for women include structural problems or scarring of the fallopian tubes and/or uterus caused by pelvic inflammatory disease (PID) or endometriosis (a condition causing adhesions and cysts), uterine fibroids or, very rarely, birth defects.

Sperm deficiencies can include low sperm production (oligospermia) or lack of sperm (azoospermia). Sperm may also have poor motility—they don't move properly once inside the female reproductive tract to achieve fertilization. Additionally, sperm cells may be malformed or may not survive long enough to reach the egg.

About one-third of identifiable causes of infertility are due to male factors and about one-third are caused by female factors. Roughly one-third of infertility is couple-related, with a combination of problems in both partners preventing conception

An estimated 20 percent of infertility cases are unexplained; the source of the problem cannot be identified.

The majority of infertility cases are treated with medication or surgery. In vitro fertilization (IVF) and other types of assisted reproductive technologies (ART)—in which barriers to successful conception are overcome in the laboratory—account for a much smaller percentage of infertility treatments.