Oscar-winning actress Rachel Weisz is getting slammed for declaring it’s OK to drink while pregnant – because experts say booze and babies don’t mix!

The 35-year-old big-screen beauty – who gave birth to a bouncing baby boy on May 31 – has sparked howls of protest after announcing moms-to-be can drink wine after the first three months of pregnancy.

"I think after that it’s fine. I mean, in Europe they drink it," raven-haired Rachel said while promoting her new film "The Fountain."

Now "The Constant Gardener" star is being blasted as irresponsible.

Even in France, the cradle of winemaking, warning labels on wine bottles that caution pregnant women against drinking will begin to appear next year.

"She is ill-informed. She needs to do her research," said Kathy Mitchell, vice president of the U.S. National Organization on Fetal Alcohol Syndrome.

"There is no known safe level of alcohol consumption during pregnancy. If you are drinking, you can have a miscarriage or your baby may have some problems."

Those problems include low birth weight, facial deformity, hearing and vision problems, growth defects, motor skill problems, memory, attention and judgment problems and language difficulties, warns NOFAS.

"Alcohol kills the baby’s cells as they’re developing," explained Mitchell. "A baby could look perfect at birth, but develop all sorts of problems as it grows up."

As for Rachel, "she should leave giving advice to doctors," said Mitchell. "And the advice is, don’t drink at all when you’re pregnant. It’s not worth the risk."