US beef may cause infertility in males: a hormone link?

30 Mar 2007

Pregnant women who eat beef from cattle treated with growth-promoting hormones may be damaging the future fertility of their unborn sons.

New findings suggest that hormones widely given to American cattle could be affecting the development of male foetuses. The study will provide the EU with fresh evidence to support its ban on imported hormone-treated beef and which has been challenged by the US Government. The EU ban has been in place since 1988.

Lead author, Professor Shanna Swan, cautioned that it was applicable only to men from North America born between 1949 and 1983. More research was needed to confirm or refute the hypothesis, she said.

Semen quality of fertile US males in relation to their mothers' beef consumption during pregnancy. (2007) S.H. Swan, F. Liu, J.W. Overstreet, C. Brazil and N.E. Skakkebaek

Human Reproduction, doi:10.1093