Edinburgh
University researchers claimed a crucial window between eight and 12 weeks of
pregnancy determined future reproductive problems.
They
believe that exposure to chemicals found in products such as cosmetics during
this period may affect later sperm production.
But
they stressed there was not yet conclusive proof this was the case.
The
research team was led by Professor Richard Sharpe of the Medical Research Council's
Human Reproductive Sciences Unit, based in Edinburgh.
Testicular
cancer
During
tests on rats, they blocked the action of androgens, which include male sex hormones
such as testosterone, for a short period in the womb.
The
experiments confirmed that if the hormones are blocked, the animals suffered fertility
problems.
Some
of the chemicals which can block the hormones are widely used in items such as
cosmetics, household fabrics and plastics.
Prof
Sharpe said the chemicals may also increase the risk of baby boys developing other
reproductive conditions in later life, including testicular cancer.
He
added that if women planning on becoming pregnant were anxious about such issues
they could avoid putting any cosmetic products on their skin which could then
be absorbed into their bodies. (bbc.co.uk)