Pregnancy Pregnancy has doubled among American women and is most common in the first trimester, according to government research.
A total of 7 percent of pregnant women, or 1 out of 14, said they used marijuana in the past month. It comes from a nationally representative health survey in 2016-17 and compares with just over 3 percent in 2002-03.
Some studies have associated marijuana use during pregnancy with increased chances of premature birth and low birth weight. Animal studies have bound high doses early in pregnancy with fetal brain abnormalities, but if typical use in humans poses similar risks, it is unknown, says Dr. Nora Volkow, director of the National Institute for Drug Addiction. "
" Because we do not know exactly how harmful it is, it is better to fail on the caution, "said Volkow, one of the authors of the government survey. Marijuana use during pregnancy" is not worth the risk, "she said Tuesday
The study was presented at a medical meeting Tuesday and published online in the Journal of the American Medical Association.
First trimester jumped from nearly 6 percent to 1
The results are based on health studies involving nearly half a million American women questioned over a period of increasing number of states r legalized marijuana for medical or leisure use. It is legal in 10 states for both applications but remains illegally federal.
A separate study of marijuana use among pregnant Canadian women published in the same journal adds evidence that pot use in pregnancy may lead to premature birth. A journal editorial commentary that resembles similar previous studies, Canadian research cannot rule out other factors that may have contributed.
The editors warned against relying on imperfect data to judge potential damage from marijuana use and said stricter research is needed. Volkow said US government restrictions on marijuana research are "very much a problem" and have hampered efforts to answer basic potato issues.
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