(CNN) - A study published in The Journal of the American Medical Association shows more pregnant women are smoking marijuana.
In 2017, seven percent of expecting moms admitted to using marijuana during their pregnancy. That's more than double from 15 years earlier.
The study also shows the usage is lightest in the first trimester when a fetus is most vulnerable.
There's no confirmed answer as to how pot affects a fetus, but the CDC said marijuana could lead to developmental problems and low birth weight.
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