High maternal estriol level in pregnancy as a predictor of surgical intervention for undescended testis.

To assess whether elevated levels of estriol (E3) in pregnancy are a factor in the fetal environment associated with undescended testes, we carried out a two-part study: case-control followed by a retrospective cohort study on cryptorchid boys born in the Sapir Medical Center (Kfar Saba, Israel). We found significantly lower pregnancy urinary E3 levels in cryptorchid newborns as compared to controls; however, subgroup comparison yielded significantly higher pregnancy unconjugated E3 levels in the infants who underwent orchiopexy as compared to those who did not.