Is usually defined as not being able to get pregnant despite trying for one year. A broader view of infertility includes not being able to carry a pregnancy to term and have a baby.
Pregnancy is the result of a chain of events. A woman must release an egg from one of her ovaries (ovulation). The egg must travel through a fallopian tube toward her uterus (womb). A man's sperm must join with (fertilize) the egg along the way. The fertilized egg must then become attached to the inside of the uterus.
While this may seem simple, in fact many things can happen to prevent pregnancy from occurring.
It is a myth that infertility is always a "woman's problem." About one third of infertility cases are due to problems with the man (male factors) and one third are due to problems with the woman (female factors). Other cases are due to a combination of male and female factors or to unknown causes.
Infertility in men
Infertility in men is often caused by problems with making sperm or getting the sperm to reach the egg. Problems with sperm may exist from birth or develop later in life due to illness or injury. Some men produce no sperm, or produce too few sperm. Lifestyle can influence the number and quality of a man's sperm. Alcohol and drugs can temporarily reduce sperm quality. Environmental toxins, including pesticides and lead, may cause some cases of infertility in men.
Infertility in women
Problems with ovulation account for most infertility in women. Without ovulation, eggs are not available to be fertilised. Signs of problems with ovulation include irregular menstrual periods or no periods. Simple lifestyle factors - including stress, diet, or athletic training - can affect a woman's hormonal balance. Much less often, a hormonal imbalance from a serious medical problem such as a pituitary gland tumour can cause ovulation problems.
Aging is an important factor in female infertility. The ability of a woman's ovaries to produce eggs declines with age, especially after age 35. About one third of couples where the woman is over 35 will have problems with fertility. By the time she reaches menopause, when her monthly periods stop for good, a woman can no longer produce eggs or become pregnant.
Other problems can also lead to infertility in women. If the fallopian tubes are blocked at one or both ends, the egg can't travel through the tubes into the uterus. Blocked tubes may result from pelvic inflammatory disease, endometriosis, or surgery for an ectopic pregnancy.
How is infertility tested?
If you have been trying to have a baby without success, you may want to seek medical help. If you are over 35, or if you have reason to believe that there may be a fertility problem, you should not wait for one year of trying before seeing a health care provider. A medical evaluation may determine the reasons for a couple's infertility. Usually this process begins with physical exams and medical and sexual histories of both partners. If there is no obvious problem, like improperly timed intercourse or absence of ovulation, tests may be needed.
For a man, testing usually begins with tests of his semen to look at the number, shape, and movement of his sperm. Sometimes other kinds of tests, such as hormone tests, are done.
For a woman, the first step in testing is to find out if she is ovulating each month. There are several ways to do this. For example, she can keep track of changes in her morning body temperature and in the texture of her cervical mucus. Another tool is a home ovulation test kit, which can be bought at drug or grocery stores.
Checks of ovulation can also be done in the doctor's office, using blood tests for hormone levels or ultrasound tests of the ovaries. If the woman is ovulating, more tests will need to be done.
Some common female tests include:
- Hysterosalpingogram: An x-ray of the fallopian tubes and uterus after they are injected with dye. It shows if the tubes are open and shows the shape of the uterus.
- Laparoscopy: An exam of the tubes and other female organs for disease. An instrument called a laparoscope is used to see inside the abdomen.
Treatment for infertility
Depending on the test results, different treatments can be suggested. Eighty-five to 90 percent of infertility cases are treated with drugs or surgery.
Various fertility drugs may be used for women with ovulation problems. It is important to talk with your health care provider about the drug to be used. You should understand the drug's benefits and side effects. Depending on the type of fertility drug and the dosage of the drug used, multiple births (such as twins) can occur in some women.
If needed, surgery can be done to repair damage to a woman's ovaries, fallopian tubes, or uterus. Sometimes a man has an infertility problem that can be corrected by surgery.
Assisted reproductive technology (ART)?
Assisted reproductive technology (ART) uses special methods to help infertile couples. ART involves handling both the woman's eggs and the man's sperm. Success rates vary and depend on many factors. ART can be expensive and time-consuming. But ART has made it possible for many couples to have children that otherwise would not have been conceived.
- In vitro fertilization (IVF) is a procedure made famous with the 1978 birth of Louise Brown, the world's first "test tube baby." IVF is often used when a woman's fallopian tubes are blocked or when a man has low sperm counts. A drug is used to stimulate the ovaries to produce multiple eggs. Once mature, the eggs are removed and placed in a culture dish with the man's sperm for fertilization. After about 40 hours, the eggs are examined to see if they have become fertilized by the sperm and are dividing into cells. These fertilized eggs (embryos) are then placed in the woman's uterus, thus bypassing the fallopian tubes.
- Gamete intrafallopian transfer (GIFT) is similar to IVF, but used when the woman has at least one normal fallopian tube. Three to five eggs are placed in the fallopian tube, along with the man's sperm, for fertilization inside the woman's body.
- Zygote intrafallopian transfer (ZIFT), also called tubal embryo transfer, combines IVF and GIFT. The eggs retrieved from the woman's ovaries are fertilized in the lab and placed in the fallopian tubes rather than the uterus.
ART procedures sometimes involve the use of donor eggs (eggs from another woman) or previously frozen embryos. Donor eggs may be used if a woman has impaired ovaries or has a genetic disease that could be passed on to her baby.