Does clomiphene in early pregnancy increase the risk of hypospadias?

Evidently not, according to a large, Danish, population-based, case–control study.

Clomiphene, which is structurally related to diethylstilbestrol (DES), has been linked to urogenital anomalies and testicular cancer in males exposed in utero. In addition, hypospadias has been reported in boys born to women exposed to DES in utero.

But this latest study calculated an odds ratio of developing hypospadias after exposure to clomiphene of only 0.48 (95% CI; 0.15–1.54). Restricting exposure to clomiphene to the first trimester and up to 30 days prior to conception did not alter the result substantially.