DRINKING any alcohol during pregnancy is unsafe and national guidelines should be changed to reflect this fact, the Australian Medical Association has warned.

The AMA has called on the National Health and Medical Research Council (NHMRC), which is reviewing its alcohol guidelines, to recommend that pregnant women not drink alcohol at all.

Current guidelines recommend pregnant women drink no more than seven standard drinks in a week and no more than two on any one day.

But AMA president Dr Mukesh Haikerwal said there was no evidence to suggest alcohol could be safely drunk at all during pregnancy.

"It's well-known that alcohol exposure can affect the structure and function of a developing foetus, interfere with the development of the central nervous system, and cause a range of disabilities,'' Dr Haikerwal said.

The AMA's call comes as a new study shows young adults whose mothers drank during early pregnancy have an increased risk of developing alcohol disorders.

The report found young adults whose mothers drank as little as three glasses of alcohol on any one occasion in the early stages of pregnancy were more than twice as likely to develop an alcohol problem later in life.

The long-term study, published in this month's issue of Archives of General Psychiatry, examined 7,223 mothers from their first prenatal visit between 1981 and 1984.

A team from the University of Queensland followed the mother and their children at birth, six months later, and five, 14 and 21 years later.

The study found 25 per cent of the 2,555 children who completed the assessment at age 21 met the criteria for a diagnoses of alcohol disorder.

"It's just one more reason for the NHMRC to recommend that pregnant women steer clear of alcohol entirely,'' Dr Haikerwal said.

"Women considering pregnancy need to know that there is no known safe level of alcohol consumption.''

But the government today failed to support a motion by Australian Democrats senator Lyn Allison calling for the recommendations to be changed.

Senator Allison's motion was defeated in the senate today.

The doctors group also supported Senator Allison's call for the government to make it compulsory for all alcohol products to carry obvious warning labels describing the health effects of alcohol.