Infertility Defined

Unlike sterility, which implies a physiological inability to conceive, infertility is associated with one’s lessened or lost ability to get pregnant and/or stay pregnant and can be either temporary or permanent. One can become infertile even after having produced one or more children. Similarly, a person can conceive and give birth even after years of unsuccessful attempts. It is also possible for a person to never get pregnant or give birth, despite the absence of physiological causes.

Clinical Definition

As defined by the World Health Organization (WHO), infertility is “a disease of the reproductive system defined by the failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual intercourse.” WHO also makes a distinction between two types of infertility: primary and secondary.

Primary Infertility

If a woman has never been pregnant or given birth to a live baby, she presents with primary infertility. This category includes women who spontaneously miscarry, provided they’ve had no successful pregnancies in the past.

Secondary Infertility

If a woman has had a previous pregnancy resulting in live birth but is now unable to become pregnant or give birth to a live baby, she presents with secondary infertility.

Statistics

According to the Reproductive Endocrinology and Infertility Center at Stanford University Medical Center, about 15 percent of couples in the United States fail to achieve pregnancy after a year of unprotected sex and, hence, are considered infertile. My reproductive endocrinologist quoted a similar figure: In his experience, one out of six couples of reproductive age have infertility problems.

Infertility affects men and women in equal proportions. Roughly one-third of infertility cases are associated with the female partner and one-third with the male partner. The remaining one-third of cases are either due to problems in both partners or are unexplained. Identifying the cause of infertility is critical for treating the condition.