Writing in the 'Hypothesis' section in the Lancet, Dr Richard Sharpe of the Medical Research Council's Reproductive Biology Unit in Edinburgh and Professor Niels Skakke baek from the University of Copen hagen say there is evidence to link increased exposure to oestrogen to male reproductive problems.
They say conditions such as failure of the testicles to descend and abormalities in the ducts of the penis have increased in the past 30 to 50 years, while there has been a 'striking drop in semen volume and in sperm counts in normal adult men'.
Particular abormalities in men have already been linked to the now- banned practice of giving women a hormone called diethylstilbestrol to prevent miscarriage.
Dr Sharpe said: 'We are beginning to understand in other areas that what we die from or suffer from may be predicted by what happened in the womb or early childhood.'
They speculate in the Lancet that male foetuses may suffer similar effects because the amount of synthetic oestrogens, one of the sex hormones necessary for female characteristics, is increasing in the environment.
This can be explained partly by changes in diet and the use of female hormones for contraception. These are excreted and can find their way into drinking water.