Australian researchers have found a link between alcohol and premature births and say women should limit their alcohol intake during pregnancy, especially in the first three months.
The researchers from the University of Western Australia, conducted a study involving 4,719 Australian women and found an almost 80% higher risk of premature births for women who drank heavily in the first trimester of their pregnancy.
The concern is that the risk remained even after they stopped drinking and this is important as women often drink alcohol, unaware that they are pregnant.
The researchers led by Dr. Colleen O'Leary say women who drink heavily early in a pregnancy - possibly before they know they are pregnant - may be raising the risk of premature delivery.
The whole issue of pregnancy and alcohol is one which raises controversy, with some experts decreeing no alcohol should be consumed while others say drinking small amounts is unlikely to harm the developing child.
As this latest study suggests that the period during which binge or heavy drinking can have the greatest effect is during the first trimester, when it is taken into consideration that as many as 40% of pregnancies are unplanned, it is clear that by the time a woman realises she is pregnant, the damage has already been done.
That the strongest link between the two appears to be in the first trimester, is unusual, and the researchers suggest that suddenly stopping the drinking of alcohol might possibly prompt inflammation which could be harmful to the developing foetus in some way.
Dr. O'Leary says the risk of pre-term birth is highest for women who drink heavily or at binge levels and women should be advised not to drink alcohol during pregnancy.
Experts say the study represents a warning to women but some say the results need to be interpreted cautiously as the relatively small number of women involved means the finding could be a statistical quirk and more research is needed to ascertain the true extent of the risk.
The researchers used data from the Telethon Institute for Child Health Research at the University of Western Australia and the National Perinatal Epidemiology Unit at the University of Oxford on 4,719 women who gave birth in Western Australia between 1995 and 1997.
The study is published in the British Journal of Obstetrics and Gynaecology.