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Overview of Infertility


Robert W. Rebar

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

Last full review/revision Sep 2020| Content last modified Sep 2020
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Infertility is usually defined as inability of a couple to conceive after 1 year of unprotected intercourse.

Infertility is defined as a disease by the World Health Organization (WHO).

Frequent, unprotected intercourse results in conception for 50% of couples within 3 months, for 75% within 6 months, and for 90% within 1 year.

Infertility can be caused by the following:

Inability to conceive often leads to feelings of frustration, anger, guilt, resentment, and inadequacy.

Couples wishing to conceive are encouraged to have frequent intercourse when conception is most likely—during the 6 days, and particularly the 3 days, before ovulation. Ovulation is most likely to occur about 14 days before the onset of the next menstrual period.

Measuring morning basal body temperature (BBT) daily can help determine when ovulation is occurring in women with regular menstrual cycles. A decrease suggests impending ovulation; an increase of 0.5° C suggests ovulation has just occurred. However, commercially available luteinizing hormone (LH) prediction test kits, which identify the midcycle LH surge, are probably the best way for women to determine when ovulation occurs and are less disruptive than measuring BBT. BBT can be useful if women cannot afford or do not have access to LH prediction kits. There is no evidence that any test determining when ovulation occurs improves the likelihood of pregnancy in couples having regular intercourse.

Excessive use of caffeine and tobacco, which can impair fertility, is discouraged.

Evidence that men > 45 are less fertile than younger men, regardless of their female partner's age, is increasing.

Evaluation of Infertility

  • A doctor's evaluation

  • Tests depending on the suspected cause

If attempts to achieve pregnancy do not result in pregnancy after ≥ 1 years, both partners are evaluated. Evaluation begins with history, examination, and counseling. Men are evaluated for sperm disorders, and women are evaluated for ovulatory and tubal dysfunction and pelvic lesions.

Evaluation is done sooner than 1 year if

  • The woman is > 35.

  • The woman is known to have decreased ovarian reserve (eg, because she has only one ovary).

  • The woman has infrequent menses.

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

  • The man is known to be subfertile or is at risk of subfertility.

Tests are done depending on the suspected cause (eg, for decreased ovarian reserve, measurement of follicle-stimulating hormone, estradiol, antimüllerian hormone, and antral follicle count, determined by transvaginal ultrasonography; for sperm disorders, semen analysis).

A couple who is being treated for infertility can experience frustration, emotional stress, feelings of inadequacy, guilt, anger, resentment, worry (eg, about finances). These feelings can lead to fatigue, anxiety, sleep or eating disturbances, and loss of concentration. Counseling and psychologic support should be offered if needed.

Support groups for couples (eg, Path2Parenthood, RESOLVE) may help. Clinicians should discuss adoption if the likelihood of conceiving is low (usually confirmed after 3 years of infertility, even in women < 35, or after 2 years of treatment).

More Information

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

  • Path2Parenthood: This web site provides information about becoming and staying pregnant, including dealing with infertility. Information is tailored for different types of people (including lesbian and gay couples and single men and women). The web site also provides resources for adoption, including finding an adoption agency and planning for payment.

  • 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+ (lesbian, gay, bisexual, transsexual or transgender, and queer and/or questioning) people have children.

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