Reproductive outcomes in men with prenatal exposure to diethylstilbestrol

Objective: To examine prenatal diethylstilbestrol (DES) exposure in relation to male reproductive outcomes. Design: Prospective observational study: Setting: Participants were identified through record review, clinical trial participation, or an obstetrics clinic. Patient(s): A total of 1,085 DES-exposed and 1,047 unexposed men. Intervention(s): Participants were exposed prenatally to DES through the mother's obstetrics care or clinical trial participation. Main Outcome Measure(s): Infertility; never fathering a pregnancy or live birth; number of pregnancies or live births fathered. Result(s): We found little evidence that prenatal DES exposure affects the likelihood of never fathering a pregnancy or live birth, or influences the mean number of fathered pregnancies or live births. Our data suggest that DES-exposed men are slightly more likely to experience infertility (relative risk [RR] = 1.3, 95% confidence interval [CI] = 1.0-1.6). The DES dose and gestational timing did not influence infertility or the number of pregnancies or live births fathered, but: results were inconsistent for dose effects on the likelihood of never fathering a pregnancy or a live birth: Conclusion(s): Prenatal DES exposure may be associated with a slightly increased risk of having an infertility experience, but does not increase the likelihood of never fathering a pregnancy or a live birth, or the number of pregnancies or live births fathered.