(Reuters Health) – Pregnant women who use marijuana to treat their nausea may be harming their unborn children, according to a warning from the National Institute on Drug Abuse (NIDA).
“Although more research is needed, there is strong reason to believe marijuana could be harmful to fetal development,” NIDA director Dr. Nora D. Volkow told Reuters Health by email. “Women who are pregnant should avoid using marijuana, even though it might seem like a 'natural' solution to their nausea.”
Writing in the Journal of the American Medical Association, Dr. Volkow and associates from NIDA in Bethesda, Maryland cite studies that show a greater risk of anemia and lower birth weights, and a higher risk of neonatal intensive care unit admission for infants, when women use marijuana during pregnancy. These children are also more likely to have developmental problems later on.
Despite these risks, marijuana use by pregnant women appears to be rising. According to a related report, the proportion of pregnant women who reported using marijuana during the past month rose from 2.37 percent in 2002 to 3.85 percent in 2014.
By 2014, 11.63 percent of pregnant women – nearly 1 in 8 – said they had used marijuana in the past year.
Dr. Qiana L. Brown from Columbia University, New York, one of the authors of that report, told Reuters Health by email, “The results from our study indicate that marijuana use among reproductive-aged women, especially those who are pregnant, is an increasing public health problem. If the current trends continue, with rates of use among pregnant women increasing as fast as they are in nonpregnant women, the U.S. may face a growing epidemic of prenatal marijuana use with associated consequences for maternal and child health.”
“While more research remains to be done on this issue, the message for pregnant women and those planning pregnancy is that for the best chances of a healthy pregnancy outcome, a prudent approach is to avoid using marijuana,” coauthor Dr. Deborah S. Hasin told Reuters Health by email.
Dr. Marion P. Jarlenski from the University of Pittsburgh, Pennsylvania, who has studied public health messages about perinatal marijuana use, told Reuters Health by email, “One point that I would like to raise, as a public health policy researcher, is that women who use marijuana in pregnancy may face legal harms from state laws requiring physicians to report to child protective services fetuses or infants who are exposed to substances. These state laws typically do not exempt marijuana use; although some state laws exempt substances that are used under medical supervision.”
NIDA is not alone in recommending against marijuana use during pregnancy. “The American College of Obstetricians and Gynecologists suggests that physicians refrain from prescribing or suggesting the use of marijuana for medicinal purposes during preconception, pregnancy, and lactation,” Dr. Brown said. “This is particularly important in the context of political and social norms in the U.S. where attitudes and policies regarding marijuana use are becoming increasingly more permissive.”