New research sparks debate over drinking while pregnant

There is very little evidence that light drinking in pregnancy harms unborn babies, a review has found.

The study found an association between light drinking and smaller babies at birth but found no evidence of other harm, including miscarriage, birth defects, developmental delay, behavioural problems and impaired intelligence.

Experts welcomed the news, with some saying Government recommendations that women stop drinking altogether in pregnancy are based on “generally weak” evidence. However, the Department of Health and the Royal College of Midwives (RCM) said the safest course of action is still for women to avoid drinking in pregnancy.

Overall, the researchers backed this view, saying the lack of evidence of harm was not the same as proof that it is fine to drink. The review, published in the journal BMJ Open, included experts from the University of Bristol and University Hospitals Bristol NHS Foundation Trust.

From 26 studies, the team found that drinking up to four units a week while pregnant, on average, was associated with an 8% higher risk of having a small baby compared with drinking no alcohol, with a range across the studies from 2% to 14%. But they said while there was an association, this did not prove a direct cause of smaller babies at birth.

The researchers said that overall there was insufficient data to “make robust conclusions”, adding that evidence on the effects of light drinking was “sparse”.

Official NHS guidance from the Chief Medical Officers for the UK published last year says pregnant women should not drink because “experts are still unsure exactly how much – if any – alcohol is completely safe for you to have while you’re pregnant”.

Up until last year, women were told they could drink up to one or two units, once or twice a week.