The subject is no doubt taboo: Women drinking, smoking cigarettes and even using illegal drugs while pregnant.

A recent study of European women found 1 in 6 admitted to drinking alcohol while pregnant.

In a study published by the Centers for Disease Control, 1 in 10 American women admitted to occasionally drinking alcohol during their pregnancy. Around 3 percent said they were binge drinkers.

“Cigarettes, marijuana, drinking every night and going out to be in situations they probably shouldn’t be in,” Corrina Tate said of the behaviors she's seen from some while pregnant.

While there’s a wide spectrum of how much each expectant mother is indulging in these types of vices, traditionally, staying away was the only acceptable advice.

However, nowadays, more and more women are bucking social norms and doctors' advice.

“At first I thought it was a joke,” said Alauna Ray.

Ray admits she was shocked the first time her mom told her she drank wine while pregnant with her. It was nothing heavy, about a glass a day.

“She was like, 'It didn't hurt you, you're fine,'" Ray said, "And I was like, 'Are you serious?'”

Still, now as an adult she's more open-minded.

"Clearly too much (alcohol) is bad, but a little bit isn't that bad,” she said.

Ray isn't the only one reconsidering the zero-tolerance attitude.

Corrina Tate said her mother was a bit more reckless.

“Personally I wouldn't (drink while pregnant), but my mom didn't know she was pregnant until she was three months (pregnant) and she partied it up and drank, and I'm a teacher so I guess I didn't come out that bad,” said Tate.

But do a couple examples of no serious harm show that it's OK for expectant mothers to start ordering cocktails?

Doctors' advice is still to stay away from alcohol in total, because the research doesn't show a particular threshold for effects on an unborn child.

“It's difficult for me to tell you how much alcohol is too much, because we don't know,” said Dr. Megan Cheney from Banner University Medical Center Women’s Unit in Phoenix.

Cheney says while alcohol can no doubt be harmful to an unborn child, causing a variety of birth defects and developmental disabilities, the exact threshold for when that happens is unknown.

“We don't know how much is a safe amount or if there is any safe amount,” Cheney said.” So the best thing we can do as a physician is to counsel them to avoid any exposures.”

While most women have been told to abstain from alcohol while pregnant in recent years several studies have found that light drinking has little or no effect on the health of an expectant mother’s baby.

According to the American Academy of Pediatrics, no alcohol is safe.

But other studies show light drinking, up to 8 drinks a week, had no effect on a baby’s health.

Alcohol, however, isn’t the only vice.

“We're seeing a trend in woman using marijuana to treat nausea and vomiting in pregnancy,” Cheney said.

Studies show 4 percent of women admit to using marijuana while pregnant, nearly doubling the number from 2002.

Research shows up to 20 percent admitted smoking cigarettes.

Emily Zygutis has seen it firsthand.

“Like 8 months, 9 months pregnant smoking cigarettes all the time nowadays,” said Zygutis.

The negative effects of smoking cigarettes are well documented.

“Premature delivery, miscarriage, still birth,” said Dr. Cheney.

Hard data on the negative effects of marijuana use during pregnancy are harder to come by.

Even so some women still wouldn't risk any of it.

“I just can't understand why anybody would do that,” said Zygutis. “Not only are you putting yourself at risk but your kid at risk too.”