Possible association of maternal factors with the higher risk of isolated true undescended testis: A population-based case-control study.

The objective of the study was to evaluate the possible association of maternal factors with the risk of isolated true undescended testis (ITUT) diagnosed at the third postnatal month because our knowledge is limited regarding the origin of ITUT. Acute and chronic diseases with related drug treatments were compared in the mothers of 2052 cases with ITUT, 24,814 male controls without any defects and 12,082 malformed male controls with other isolated defects in the population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996. Prospective medically recorded endometriosis before conception of the study pregnancy in the mothers of 39 cases was associated with a higher risk of ITUT in their sons (odds ratio (OR) with 95% confidence interval [CI]: 2.42, 1.71-3.42). Dihydrogesterone treatment in the first trimester of pregnancy also showed association with the higher risk of ITUT but based on only five pregnant women. In conclusion, endometriosis before pregnancy may have a role in the origin of ITUT.