Richer, older, more educated Australians are more likely to have a tipple during pregnancy than their younger less well-off peers, according to new research.
But that's half a drink in a sitting and two at the most.
It's younger, less educated single women who are more likely to guzzle five or more units in a sitting, according to a study published in the latest issue of the Medical Journal of Australia.
A report on the study emphasises that Australian guidelines advocate total abstinence and highlights the danger of "birth defects, growth and developmental abnormalities and fetal mortality".
It shows most women heed doctors' orders and fully abstain when they know they are pregnant.
Based on data from 2007 to 2011, the report shows a big drop in light drinking and little change in heavy drinking.
Those who admit drinking any alcohol after the first trimester have fallen from 42 per cent to 26 per cent in the five years.
The proportion of heavy drinkers after the first trimester is steady around 2.5 per cent.
Lead author Dr Cate Cameron, a senior research fellow at Griffith Health Institute, says the researchers have assumed women are aware they are pregnant after the first trimester.
For women who say they drank alcohol at any stage of their pregnancy, the figure falls from 53 per cent in 2007 to 35 per cent in 2011.
Dr Cameron says more needs to be done to improve the positive results of public health campaigns.
And women with a chance of becoming pregnant should moderate their drinking, just in case.
