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Overview of Infertility


Robert W. Rebar

, MD, Western Michigan University Homer Stryker M.D. School of Medicine

Reviewed/Revised Oct 2022
Topic Resources

Infertility is usually defined as the inability to achieve a pregnancy after 1 year of regular sexual intercourse without birth control.

Frequent intercourse without birth control usually results in pregnancy:

  • For 50% of couples within 3 months

  • For 75% within 6 months

  • For 90% within 1 year

To maximize the chance of pregnancy, couples should have frequent intercourse in the 6 days—and particularly the 3 days—before the ovaries release an egg (ovulation). Ovulation usually occurs in the middle of the menstrual cycle, which is about 14 days before the first day of a women's next period.

Two of the more common methods women can use to estimate when ovulation occurs are

  • Home ovulation prediction kits (probably the best way)

  • Measurement of body temperature at rest (basal body temperature)

Home ovulation prediction kits are the most accurate method that can be used at home. These kits are used to detect an increase in luteinizing hormone in the urine. (Luteinizing hormone stimulates the ovaries to trigger ovulation.) Usually, this increase occurs 24 to 36 hours before ovulation. Women usually need to repeat the test for several consecutive days, so kits typically include five to seven sticks. The sticks can be held under a stream of urine or dipped into urine that is collected in a clean, preferably sterile, container.

Basal body temperature measurement is another option. If women have regular periods, they can estimate when ovulation occurs by measuring their temperature each day before they get out of bed. A decrease suggests that ovulation is about to occur. An increase of 0.9° F (0.5° C) or more suggests ovulation has just occurred. However, this method is time-consuming and is not reliable or precise. At best, it predicts ovulation within 2 days after the fact.

Whether estimating when ovulation will occur increases the chance of pregnancy for couple who have intercourse regularly is unknown. However, estimating when ovulation will occur is likely to help couples who do not have intercourse regularly estimate when the best time for intercourse is.

Up to one in five couples in the United States do not conceive for at least a year and are thus considered to have infertility. However, of the couples who have not conceived after a year of trying, more than 60% conceive eventually, with or without treatment.

Causes of Infertility

The cause of infertility may be due to problems in the man, the woman, or both:

Consuming a lot of caffeine and/or using excess tobacco may impair fertility in women and should be avoided. There is no clear evidence that drinking a lot of coffee impairs fertility. However, some data suggest that for women who drink more than 5 to 6 cups of coffee a day, it may take longer to become pregnant.

Some studies have reported that men over 45 are less fertile than younger men.

Diagnosis of Infertility

  • A doctor's evaluation

  • Various tests depending on the suspected cause

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

  • The woman is over 35 (usually after 6 months of trying to become pregnant).

  • The woman's menstrual periods occur infrequently (fewer than nine times a year).

  • The woman has a previously identified abnormality of the uterus, fallopian tubes, or ovaries.

  • Doctors have identified or suspect problems with sperm in the man.

Age is a factor, especially for women. As women age, becoming pregnant becomes more difficult, and the risk of complications during pregnancy increases. Fertility may start to decrease around age 35, and after 40, becoming pregnant becomes even more difficult.

Tests are done depending on the suspected cause. They may include

  • For problems with eggs: Blood tests to measure the hormones involved in the release of eggs (ovulation) by the ovaries, such as follicle-stimulating hormone

  • For problems with ovulation: Ultrasonography to determine whether and when ovulation occurs

  • For sperm disorders: Semen analysis

Treatment of Infertility

  • Treatment of the cause

  • Sometimes medications

  • Sometimes assisted reproductive technologies

  • Measures to lessen stress, including counseling and support

The goals of treatment are

  • To treat the cause of infertility if possible

  • To make conception more likely

  • To reduce the time needed to conceive

Even when no cause of infertility can be identified, the couple may still be treated. In such cases, the woman may be given medications that stimulate several eggs to mature and be released— fertility medications Treatment Women may have infertility if the ovaries do not release an egg each month, as usually occurs during a menstrual cycle. Ovulation problems can result from dysfunction of the part of the brain... read more . Examples are clomiphene, letrozole, and human gonadotropins. These medications are most helpful for women who have problems with ovulation Infertility Problems With Ovulation Women may have infertility if the ovaries do not release an egg each month, as usually occurs during a menstrual cycle. Ovulation problems can result from dysfunction of the part of the brain... read more . However, fertility medications increase the chances of having more than one fetus.

Assisted reproductive technologies may result in more than one fetus.

While a couple is being treated for infertility, one or both partners may experience frustration, emotional stress, feelings of inadequacy, and guilt. They may alternate between hope and despair. Feeling isolated and unable to communicate, they may become angry at or resentful toward each other, family members, friends, or the doctor. The emotional stress can lead to fatigue, anxiety, sleep or eating disturbances, and an inability to concentrate. In addition, the financial burden and time commitment involved in diagnosis and treatment can cause marital strife.

These problems can be lessened if both partners are involved in and are given information about the treatment process (including how long it takes), regardless of which one has the diagnosed problem. Knowing what the chances of success are, as well as realizing that treatment may not be successful and cannot continue indefinitely, can help a couple cope with the stress.

Information about the following is also helpful:

  • When to end treatment

  • When to seek a second opinion

  • When to consider adoption

For example, if pregnancy has not occurred after 3 years of attempting it or after 2 years of being treated for infertility, the chance of pregnancy is very low. Ideally, couples should ask for this information before treatment is begun.

Counseling and psychologic support, including support groups such as RESOLVE and Family Equality, can help.

More Information

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

  • Family Equality: This organization aims to promote equality for LGBTQ (lesbian, gay, bisexual, transsexual or transgender, and queer and/or questioning) families and to provide information about building families. The web site includes information about becoming pregnant, (including costs) and about adoption, parenting and legal issues pertaining to the LGBTQ community..

  • RESOLVE: The National Infertility Association: This web site provides general information about infertility, possible treatments and solutions (such as adopting or using a surrogate), and financial issues, as well as links to support groups, ways to manage stress, and advice for friends and family. It also includes resources to help LGBTQ+ people have children.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Cafcit, NoDoz, Stay Awake, Vivarin
Clomid, Serophene
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