Almost half of Australia's pregnant women drink alcohol throughout their pregnancy, and some even admit to binge drinking in the final months before giving birth, according to a study issued on Wednesday.

The women who were prepared to drink on were also more likely to smoke during their pregnancy, according to the study of 4,700 mothers in Western Australia.

However, the bad habit put these women at the risk of having their baby prematurely, according to the research which was released on Wednesday by WA's Telethon Institute for Child Health Research.

"Our research shows pregnant women who drink more than one to two standard drinks per occasion - and more than six standard drinks per week - increase their risk of having a premature baby," the institute's researcher Colleen O'Leary said on Wednesday.

This was the case even if the women stopped drinking before their second trimester, O'Leary said.

"The risk of pre-term birth is highest for pregnant women who drink heavily or at binge levels, meaning drinking more than seven standard drinks per week, or more than five drinks on any one occasion," Australian Associated Press quoted her as saying.

The study found a low birth weight was more likely to be caused by a mother's smoking rather than drinking.

"Women should be advised that during pregnancy, drinking alcohol above low levels increases the risk to the baby and that the safest choice is not to drink alcohol," O'Leary said.

(Xinhua News Agency January 22, 2009)