Infertility is defined as the inability to conceive after 1 year of unprotected intercourse of reasonable frequency. It can be subdivided into primary infertility, that is, no prior pregnancies, and secondary infertility, referring to infertility following at least one prior conception.
Conversely, fecundability is the ability to conceive, and data from large population studies show that the monthly probability of conceiving is 20 to 25 percent. In those attempting conception, approximately 50 percent of women will be pregnant at 3 months, 75 percent will be pregnant at 6 months, and more than 85 percent will be pregnant by 1 year (Fig. 19-1) (Guttmacher, 1956; Mosher, 1991).
Time required for conception.
Infertility is common and affects 10 to 15 percent of reproductive-aged couples. Of note, even without treatment, approximately half of women will conceive in the second year of attempting. According to the National Survey of Family Growth, the percentage of married women who reported infertility fell from 8.5 percent in 1982 to 6.0 percent in 2006 to 2010. In comparison, the percentage of women aged 15 to 44 years who had ever used infertility services increased from 9 percent in 1982 to 12 percent in 2002, with a peak of 15 percent in 1995 (Chandra, 2013, 2014). Interpretation of these data is complicated by ongoing changes in marriage rates, intentional delays in childbearing, and socioeconomic and educational status changes in a growing immigrant community. Nevertheless, well-publicized successes in infertility treatment now give patients greater hope that medical intervention will help them achieve their goal.
Most couples are more correctly considered to be subfertile, rather than infertile, as they will ultimately conceive if given enough time. This concept of subfertility can be reassuring to couples. However, there are obvious exceptions, such as the woman with bilaterally obstructed fallopian tubes or the azoospermic male. In general, infertility evaluation is for any couple that has failed to conceive in 1 year. But, several scenarios may prompt earlier intervention. For example, to delay assessment in an anovulatory woman or a woman with a history of severe pelvic inflammatory disease (PID) may not be appropriate. Of particular note, fecundability is highly age-related, with a significant decrease beginning at approximately 32 years of age and more rapid decline after age 37 (American Society for Reproductive Medicine, 2014a). This decline in conception rates is associated with an increase in poor pregnancy outcomes, primarily due to increased aneuploidy rates. Thus, most experts agree that evaluation is considered after only 6 months in women older than 35 years.
Prior to initiating infertility treatment, a patient’s health status must be optimized for an anticipated pregnancy. Ideally, these issues are addressed prior to referral to an infertility specialist whenever possible. Topics ...