Just one or two glasses of wine a week could reduce a woman’s chance of becoming pregnant by a third, say researchers.

Three or more glasses cuts the odds of conception by two-thirds. Experts say even low levels of alcohol can harm the development of unfertilised eggs.

The findings suggest that success can be impaired even if women stick within limits recommended by the NHS.

Health workers say women trying for a baby should have no more than three small glasses of wine a week – but preferably none at all.

Dr Dara Godfrey, of New York fertility clinic Reproductive Medicine Associates, carried out research on 91 women undergoing IVF treatment.

She told a meeting of the American Society for Reproductive Medicine in Boston that teetotal women in the study had a 90 per cent chance of becoming pregnant.

Those who drank throughout the week reduced their odds by up to 70 per cent. But binge-drinking could make the problem worse, she said.