In utero exposure to environmental estrogens and male reproductive health: a systematic review of biological and epidemiologic evidence.

In recent years, chemicals with hormone-like properties have become a topic of scientific and public discussion. It has been hypothesized that prenatal exposure of the male fetus to endocrine disruptors may be responsible for a series of outcomes, such as hypospadias and cryptorchidism. The purpose of this study was to review the endocrine disruption hypothesis, to present the relevant supporting evidence, to summarize the current knowledge, to identify gaps and limitations in the interpretation of published data, and to define future directions in research. An update on environmental estrogens was followed by an assessment of the biological plausibility and evidence connecting the environmental chemicalization with adverse reproductive outcomes in males. Subsequently, we carried out a systematic review of human studies attempting to document a direct effect of exogenous estrogens on the male reproductive system. The results do not support with certainty the view that environmental estrogens contribute to an increase in male reproductive disorders, neither do they provide sufficient grounds to reject such a hypothesis.