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Overview of Infertility


Robert W. Rebar

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

Reviewed/Revised Sep 2022

Infertility is usually defined as the inability to conceive after 1 year of regular, unprotected sexual 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 anxiety, sadness, 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 time-consuming 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, tobacco, or alcohol, 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

  • Tests depending on the suspected cause

If attempts to achieve pregnancy do not result in pregnancy after ≥ 1 year, 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 pathology.

Evaluation is done sooner than 1 year if

  • The woman is > 35 years old.

  • 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 and antimüllerian hormone and antral follicle count, determined by transvaginal ultrasonography; for sperm disorders, semen analysis).

Support groups for couples (eg, Family Equality, 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).

Treatment of Infertility

  • Treatment of the primary cause

  • Sometimes medications to induce ovulation or spermatogenesis

  • Sometimes assisted reproductive techniques

The primary cause of male or female infertility is treated, if possible. For example, structural abnormalities of the reproductive tract (eg, testicular varicocele, uterine leiomyomas) or endocrine abnormalities (eg, pituitary adenoma, thyroid disorders) can be treated. Patients should be encouraged to make changes to minimize modifiable risk factors. For example, smoking cessation for smokers, weight loss for overweight patients, no or moderate consumption of alcohol, and consumption of a balanced diet (with vitamins if needed) are recommended.

In general, treatment is directed at improving the likelihood of conception by increasing the availability of high-quality oocytes (eg, ovulation induction, egg donation) or sperm (eg, gonadotropin medications to induce spermatogenesis, sperm donation) and by using procedures to assist contact between the oocyte and sperm to achieve fertilization (eg, intrauterine insemination, in vitro fertilization).

People with infertility may experience sadness, anxiety, frustration, emotional stress, feelings of inadequacy, guilt, or anger. These feelings can lead to sleep or eating disturbances or clinical anxiety or depression. Counseling and behavioral health support should be offered if needed.

Giving both partners information about the treatment process is helpful. Such information includes

  • What the chances of success are

  • What the process involves, including time and costs

  • When to end treatment

  • When to consider adoption

Support groups for infertile people (eg, Family Equality, 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 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

Drug Name Select Trade
Cafcit, NoDoz, Stay Awake, Vivarin
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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