MIAMI -- Drinking alcohol during pregnancy puts infants at risk of developmental problems and brain damage, but one in 10 US women say they drink while pregnant, U.S. health authorities said Thursday.

Pregnant women's binge drinking habits also raised concern among researchers, who said they found that pregnant women who drink reported more binge drinking episodes than non-pregnant women.

"We know that alcohol use during pregnancy can cause birth defects and developmental disabilities in babies, as well as an increased risk of other pregnancy problems, such as miscarriage, stillbirth, and prematurity," said Coleen Boyle, director of the U.S. Centers for Disease Control and Prevention's National Center on Birth Defects and Developmental Disabilities.

"This is an important reminder that women should not drink any alcohol while pregnant. It's just not worth the risk."

Ten per cent of pregnant women between the ages of 18 and 44 reported drinking alcohol in the past month, according to the CDC's Morbidity and Mortality Weekly Report (MMWR).

About a third of pregnant women who drink -- or 3.1 per cent of pregnant women overall -- admitted to binge drinking, meaning they consumed four or more alcoholic beverages in one sitting.

The frequency of these binge-drinking episodes was higher than seen among non-pregnant women -- 4.6 episodes in the last month, compared to 3.1 episodes among women who were not pregnant.

Experts say the danger of drinking is it may cause fetal alcohol spectrum disorders (FASD), which have no cure and can damage a child for life.

"Community studies estimate that as many as two to five percent of first grade students in the United States might have an FASD," said the report.

The survey was based on a landline and cell phone survey of the U.S. population, and relied on data from all 50 states and the District of Columbia for women aged 18-44 years.

"Women who are pregnant or might be pregnant should be aware that there is no known safe level of alcohol that can be consumed at any time during pregnancy," said Cheryl Tan, lead author of the study and an epidemiologist in CDC's National Center on Birth Defects and Developmental Disabilities.

"All types of alcohol should be avoided, including red or white wine, beer, and liquor."