A review of published epidemiological studies
2006 Study Abstract
Male reproductive disorders in humans and prenatal indicators of estrogen exposure. A review of published epidemiological studies. Reports of an increase in male reproductive disorders in several countries led to the hypothesis that estrogens during fetal life may cause reduced sperm counts, cryptorchidism, hypospadias and testicular cancer. So far the hypothesis is based on animal studies and reports from the wild life.
We systematically searched the epidemiological literature for evidence linking indicators of prenatal serum levels of maternal estrogens with sperm density, hypospadias, cryptorchidism and testicular cancer in humans. Indicators of fetal estrogen exposure included direct measurements, recorded intake of hormones (diethylstilbestrol (DES), oral contraceptives (OCs) and estrogens), pregnancy conditions with known deviant estrogen level as for instance twin pregnancies and some environmental exposures.
We identified four studies focussing on estrogens given prenatally, mainly DES studies.
- Physical examination of men from Dieckman’s cohort revealed a higher number of men with hypoplastic testes among exposed [OR = 4.36 (1.9–11.4) calculated by the author] and cryptorchidism was more prevalent among exposed men with hypoplastic testes, but data on the occurrence of cryptorchidism among all men are not given.
- Vessey et al. found an equal frequency of cryptorchidism in the DES and the placebo group among offspring from Sweyer and Law’s DES cohort from 1954. Selection bias in this study is less likely since information was obtained from GP’s, blinded for exposure status. The time of entry and the total dose of DES were similar in these two DES studies (11.6 and 11.5 g, respectively).
- Two case-referent studies using data on estrogen prescription from medical records found increased risk of cryptorchidism [RR 1.9 (95%CI: 0.5–6.6)  and 2.8 (95% CI: 0.9–8.8)…
- Male reproductive disorders in humans and prenatal indicators of estrogen exposure. A review of published epidemiological studies, Reproductive toxicology, NCBI PubMed, PMID: 16005180, 2006 Jan.
- Featured image Nik Shuliahin.