Nice said there was "no consistent evidence" to show a small amount of alcohol damaged unborn children.

The guidelines are out for consultation and are due to be published in March.

A Nice spokesman said, "The experts developing this guideline have carried out a systematic review of all the evidence available on the risks of drinking alcohol in pregnancy.

"The recommendations in the draft guideline are based on this evidence.

"The experts have concluded that there is no consistent evidence of adverse effects from low to moderate alcohol during pregnancy (less than one drink or 1.5 units per day), but the evidence is probably not strong enough to rule out any risk."

The risks of birth defects, miscarriage and behavioral problems among children of drinking mothers were considered.

The experts concluded women should avoid alcohol only during the first trimester but said drinking led to a slightly higher risk of miscarriage.

A small 125ml glass of red or white wine is just under 1.5 units, the Department of Health said. Half a pint of 5% lager or strong cider or a bottle of alcopop are also 1.5 units. A 25ml measure of spirits is one unit.

The Royal College of Obstetricians and Gynaecologists said the "safest option" was for pregnant women to abstain from drinking.

The government has said women who do choose to drink during pregnancy should have no more than one to two units of alcohol once or twice a week.

From the October 22, 2007, Prepared Foods e-Flash