Maternal pregnancy serum level of heptachlor epoxide, hexachlorobenzene, and β-hexachlorocyclohexane and risk of cryptorchidism in offspring

Prenatal exposure to environmental endocrine disrupters has been postulated to cause adverse effects on male reproductive health. Exposure to organochlorine pesticides with anti-androgenic and estrogenic potency has been shown to interfere with the sex-hormone-dependent process of testicular descent in animal models. We examined the relation between serum levels of the pesticides heptachlor epoxide (HCE), hexachlorobenzene (HCB), and β-hexachlorocyclohexane (β-HCCH) in pregnant women, and the occurrence of cryptorchidism in their sons. These three pesticides were previously suggested as risk factors for cryptorchidism. In a nested case–control design, we compared serum levels between mothers of cases (n=219) and controls (n=564), selected from the Collaborative Perinatal Project, a US birth cohort study of pregnancies in 1959–1966. The offspring of mothers with HCE levels above the 90th percentile compared to those below the 10th percentile had an adjusted odds ratio of cryptorchidism of 1.2 (95% confidence interval 0.6–2.6); for β-HCCH the odds ratio was 1.6 (0.7–3.6). For HCB the adjusted odds ratio was near one. These results provide little support for an association of cryptorchidism with exposure to low levels of HCE or HCB. For β-HCCH the findings were somewhat suggestive of an association but were inconclusive.