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Studies show more women in the U.S. are using cannabis during pregnancy; the Food and Drug Administration would rather they did not. The FDA is advising women not to use cannabis in any form when pregnant or breastfeeding because it may put their infants at risk. NPR's Rhitu Chatterjee reports on what researchers are learning.
RHITU CHATTERJEE, BYLINE: Twenty-eight-year-old Jennifer had a rough start to her pregnancy. We aren't using her last name to protect her privacy. Jennifer says she had such intense nausea and vomiting that she couldn't eat anything.
JENNIFER: I couldn't keep down prenatals. I've been anemic my entire adult life, and I couldn't keep down iron pills or food.
CHATTERJEE: She lost 11 pounds in the first couple of weeks and began to worry that she wasn't getting enough nutrients to support the pregnancy.
JENNIFER: I was basically in this space where I felt like I wanted to be a new mom and take care of my child, and I wasn't able to do that.
CHATTERJEE: That's when her husband bought her an iced tea with CBD and THC in it - those are the two main components of the drug. And Jennifer took a few sips.
JENNIFER: Within 20, 30 minutes, I felt completely different, like a whole new person.
CHATTERJEE: Her nausea went away, and she was able to eat her first full meal in weeks. Still, she was worried - could the drug affect her baby? She looked online for answers but couldn't find anything conclusive.
JENNIFER: I was frustrated that I couldn't really find any information.
CHATTERJEE: That's not surprising says Daniel Corsi, an epidemiologist at the University of Ottawa in Canada.
DANIEL CORSI: The science is relatively new.
CHATTERJEE: He says early studies found that use of the drug during pregnancy was associated with a higher risk of premature birth. But, he says, those couldn't say for sure whether the effects were due to cannabis or other factors.
CORSI: Because cannabis users also tended to use other things in pregnancy, including tobacco.
CHATTERJEE: Which also hurts pregnancy outcomes. But Corsi and his colleagues recently published a study where they compared pregnant women using cannabis with those who didn't and of similar ages, backgrounds and with similar use of tobacco and other substances. They still found the same adverse effects.
CORSI: There was higher rates of premature birth and smaller size at birth.
CHATTERJEE: Other analyses have confirmed those findings. And research on laboratory animals suggests that cannabis could have longer-term effects, says Nora Volkow. She directs the National Institute on Drug Abuse.
NORA VOLKOW: Studies have shown, unequivocally, that exposure to pregnant animals results in interference with the development of the brain.
CHATTERJEE: But Volkow acknowledges that it can be difficult to translate findings from animal studies to humans. And there are still big gaps in our understanding. For example, how much marijuana are pregnant women using? Or is there a safe dose? We may not have the answers for a while, she says, but...
VOLKOW: In the meantime, we know sufficiently to say we have to be cautious. Why take the risk?
CHATTERJEE: For Jennifer, she took the risk cautiously, only taking a few sips here and there.
JENNIFER: I ultimately came to the conclusion that lack of nutrition is far worse than the little bit of marijuana that I'm consuming.
CHATTERJEE: And after the first trimester, when the nausea went away, she stopped.
Rhitu Chatterjee, NPR News.
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