Infertility

Reviewed/Revised Apr 2024
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What is infertility?

Infertility is a disease defined by the inability to get pregnant or the need for medical help to get pregnant.

For most couples, having frequent sex without birth control results in a pregnancy within a year. For more than half of couples, pregnancy happens within the first 3 months.

  • Not getting pregnant can be caused by problems with the man, the woman, or both

  • For women, eggs may not be released from the ovary or the eggs may not get through the tubes that lead to the womb

  • For men, there may be a problem making sperm, or the sperm may not get through the tubes that lead to the penis

  • Doctors do tests to look for the cause of infertility

  • For the highest chance of pregnancy, couples should have sex in the 3 days right before ovulation

  • If having sex at the right time doesn't work, there are medications and medical techniques to help women get pregnant

Locating the Female Reproductive Organs

What is ovulation?

Ovulation is the release of an egg from a woman’s ovary.

Typically, women ovulate about halfway between one period and the next. For example, if your menstrual cycle is 28 days (counting from the first day of one period to the first day of the next period), you usually ovulate around day 14.

A woman is most likely to get pregnant if she has frequent sex during the 3 days before ovulation. This is when there's the best chance for the egg to be exposed to sperm.

If you want to figure out when you ovulate, there are better ways than counting days. These methods are more accurate:

  • Measuring body temperature

  • Using a home ovulation predictor kit

Body temperature: Take your temperature at the same time each morning before you get out of bed. This is your basal body temperature. Your temperature will be a little lower starting a few days before ovulation. Then when you ovulate, your temperature goes up and stays up until your next period.

Ovulation predictor kit: You can buy a home ovulation prediction kit in the drugstore. The kit tests your urine for a hormone that goes up right before you ovulate. These kits are more accurate than the body temperature method.

What causes infertility?

Infertility in women is most often caused by:

  • Lack of ovulation—sometimes, the woman’s ovaries don’t release an egg each month

  • Blocked or damaged fallopian tubes (the tubes that carry eggs from the ovaries to the uterus)

  • Problems in the abdomen or in the uterus (womb)

Lack of ovulation has many possible causes. For example, it can be due to hormone problems, polycystic ovaries, eating disorders, early menopause, too much exercise, and use of certain medications.

Blocked fallopian tubes prevent sperm from reaching the egg or keep a fertilized egg from entering the uterus. Tubes may be blocked by scar tissue. Scar tissue may result from infections such as pelvic inflammatory disease, a ruptured appendix, or having had a pregnancy in the tubes (ectopic pregnancy).

Problems in the abdomen or womb can keep an egg from entering the fallopian tubes or keep a fertilized egg from attaching inside the uterus. Problems in the abdomen or womb include scar tissue from previous surgery, birth defects of the uterus, and abnormal growths such as endometriosis or fibroids.

Other things that make it harder for a woman to get pregnant include getting older, having diabetes, being overweight, drinking a lot of coffee (more than 5 or 6 cups a day), and smoking.

Infertility in men is most often caused by:

  • Low numbers of sperm (low sperm count) or slow-moving sperm

  • Problems getting sperm from the testicles to the penis

Low sperm count has many possible causes. It can be due to hormone problems, too much heat on the testicles, infections such as mumps, undescended testicles, and varicose veins of the testicles. Certain medical treatments, including many medications, chemotherapy, and radiation, can affect sperm count. Too much alcohol or marijuana can also lower the number of sperm.

Problems getting sperm from the testicles to the penis may happen if the pathway is blocked or damaged because of previous surgery or certain birth defects. Diabetes or nerve problems can also affect how sperm gets from the testicles to the penis.

Sometimes doctors can't figure out the reason why a couple is infertile.

When should I see a doctor about infertility?

The diagnosis of infertility requires a thorough assessment of both partners. Usually, the assessment is done after at least 1 year of trying to get pregnant. However, it is done sooner if

  • A woman is 35 or older and has been trying to get pregnant for more than 6 months

  • A woman doesn't have regular periods or has very painful periods

  • A woman has a known problem with her uterus, fallopian tubes, or ovaries

  • Doctors have identified or suspect problems with sperm in a man

What tests will my doctor do?

Doctors may do tests, including:

  • Blood tests, including hormone tests

  • X-rays, ultrasound, and other imaging tests of the woman's womb and fallopian tubes or the man's sex organs

  • In women, using a viewing tube to look inside the pelvis or womb

  • In men, sperm count and looking at the sperm under a microscope to see if they're normal in shape and move normally

  • Sometimes, genetic tests

How do doctors treat infertility?

Doctors will treat the cause of infertility, if known. They'll advise the couple to stop smoking and to not drink too much alcohol, to watch their weight, and to exercise regularly.

Sometimes doctors can’t identify the cause of infertility. But they can still treat you to raise the chances of getting pregnant or getting pregnant sooner.

Doctors may:

  • Give the woman medicine that stimulates the ovaries to release eggs

  • Do intrauterine insemination (IUI), a procedure in which doctors use a syringe to place sperm into the womb

  • Do surgery to treat blocked tubes or other problems

In some cases, doctors may recommend assisted reproductive technologies (ARTs). With ART, a woman's eggs are fertilized with a man's sperm in the laboratory to produce one or more embryos. Fertilizing eggs in a laboratory is called in vitro fertilization. The embryo can then be put into the woman's womb.

These treatments don't always work. Couples may want to consider adoption as an alternative to pregnancy.

Being treated for infertility can be very stressful. You may feel frustrated, upset, or guilty. This can put a strain on your relationship. Infertility treatment can also cost a lot and take a lot of time. The stress can lead to anxiety, sleep or eating problems, and can interfere with your life and work. This is normal. Counseling and support groups can help.

Where can I get more information about infertility?

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