Self-reported use of pharmaceuticals and primary ovulatory infertility.

Over 1.5 billion prescriptions were filled by pharmacies in 1990, but little information exists on the effect that pharmaceutical agents have on female reproductive capacity. As part of a case-control study of risk factors for primary ovulatory infertility, we examined self-reported use of several prescription and nonprescription medications in 597 women with ovulatory infertility and 3,833 controls admitted for delivery at seven hospitals. Only women reporting use of a drug for at least 6 months, beginning before the onset of infertility in cases and before conception in controls, were considered exposed. An elevated risk of ovulatory infertility was found for women who ever used thyroid preparations [relative risk (RR) = 2.3, 95% confidence interval (CI) = 1.5-3.5] or antidepressants (RR = 2.9, 95% CI = 0.9-8.3), although the latter estimate was based on only five cases who reported having taken antidepressants. Current users of tranquilizers and ever-users for more than 2 years were also at greater risk of infertility than never-users (RR = 3.2, 95% CI = 1.1-8.5 and RR = 2.9, 95% CI = 0.8-11, respectively). Women who used asthma medication before age 21 had more than a twofold increase in risk of ovulatory infertility (RR = 2.5, 95% CI = 1.0-5.9).