Men’s ability to father children may be affected by their mothers’ drinking habits when they were in the womb, a study has suggested.
Unborn sons exposed to high levels of alcohol when being carried by their mothers could suffer from impaired fertility as adults.
The research found that while the men may not be completely infertile, they might find it more difficult to impregnate their partners.
Men whose mothers consumed 4.5 or more drinks a week had sperm concentrations a third lower than those of men exposed to little or no alcohol in the womb, the study found.
In some cases, the most-exposed men had sperm concentrations well below the accepted threshold point for reduced fertility.
Study leader Dr Cecilia Ramlau-Hansen, from Aarhus University Hospital in Denmark, said: “We found that if mothers drink alcohol during pregnancy, sperm concentrations in sons will decline.
“This might result in a son, when he wants to be a father, needing more time to make his partner pregnant.
“I can’t say the man will be infertile. But we see this lower sperm concentration at higher levels of alcohol exposure, and we know that it takes more time to make your partner pregnant the lower sperm concentration you have.”
The findings were presented at the annual meeting of the European Society of Human Reproduction and Embryology in Rome, and reported in the journal Human Reproduction.