Dear Mr. Dad: My wife and I are in our early 30s and want to start a family. To be perfectly honest, we’ve been regular weed and tobacco smokers for years. To get ready for pregnancy, though, we both quit cigarettes cold turkey. Beyond that, we disagree. I think we should also give up marijuana. My wife has reluctantly agreed to stop smoking, but she has a medical marijuana card and says that the edible kind is perfectly healthy and won’t hurt the baby. So two questions: Is consuming marijuana during pregnancy okay? If not, are the tablets or drops any better than smoking?

A: To be blunt, consuming marijuana during pregnancy is a terrible—and potentially dangerous—idea. And while the non-inhaled delivery mechanism may be less dangerous, they’re still a long, long way from “perfectly healthy.”

I just came back from a conference where one of the speakers, Ira Chasnoff, M.D., talked about this exact topic. To sum up his findings about marijuana, “contrary to popular perception, it is not a harmless drug, especially when used during pregnancy.” But let’s dig a little deeper.

Chasnoff cites a large study done by the US National Birth Defects Prevention Center that found that fetuses exposed to marijuana during the first four weeks of pregnancy are at increased risk of developing anencephaly (a severe birth defect that keeps a major chunk of the brain and skull from developing).  Prenatal exposure to marijuana may also interfere with the neurotransmitter systems that govern the baby’s cognitive and emotional function.

And the effects of prenatal marijuana exposure can last a lifetime. According to Chasnoff, at age six, children who had been exposed to marijuana in utero had “lower verbal reasoning scores and deficits in composite, short-term memory, and qualitative intelligence scores.” Ten-year-olds prenatally exposed to marijuana were more likely to be hyperactive and impulsive, have attention problems, and be depressed than their unexposed agemates. Depression and attention issues at age 10 are major predictors of delinquency at age 14. And 14-year-olds whose mothers were heavy users during the first trimester, had lower scores on spelling, reading, and math. The effects of prenatal exposure continue to show up well into young adulthood—and possibly beyond.

As you might suspect, not everyone agrees about just how bad marijuana during pregnancy is for the baby.  A study done at the Washington University School of Medicine in St. Louis, for example, found a connection between marijuana smoking and perterm birth and/or low birthweight. But since many mothers who smoke dope also smoke cigarettes—which are indisputably linked to preterm birth and low birthweight—the researchers couldn’t be sure that the negative effects were caused by the marijuana. However, those researchers were very careful to note that they aren’t suggesting that “marijuana use during pregnancy should not be encouraged or condoned.”

To answer your question about the relative danger of smoking dope vs. eating it, I spoke to two doctors, including Chasnoff. Both believe that smoking is more dangerous because the psychoactive chemical in the plant, THC, goes straight from the lungs into the bloodstream. Ingesting marijuana via the stomach, however, takes it through the liver, where some of the THC may be filtered out, thereby reducing the negative effects.

Bottom line: At the very least, neither you nor your wife should smoke, eat, drink, or consume marijuana in any other way while she’s pregnant. If your wife needs more convincing, contact Dr. Chasnoff directly through his website, http://www.ntiupstream.com and ask for a copy of his study.  Even if your wife is on the fence, it’s completely irresponsible of her to subject your baby to a potential hazard that’s 100% preventable.

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