More Pregnant Moms Are Smoking Weed, and We’re Not Sure What That Means

The effects are still essentially unknown.

Dec 20 2016, 3:00pm

Image: Unsplash/Pixabay

Pregnant mothers are apparently reaching for their bongs more than ever.

According to a new research letter in the Journal of the American Medical Association, more women are using cannabis products when pregnant, often to treat morning sickness. The prevalence of expecting women who report using cannabis in the past month has increased over the past decade, Dr. Nora Volkow, director of the National Institute on Drug Abuse, told Motherboard.

In 2002, 2.37 percent of US women reported marijuana use during pregnancy. The rate went up to 3.85 percent who reported doing so in 2014, according to the report. Volkow added that the climb was aligned with the prevalence of cannabis use among non-pregnant women and other adults, who are also smoking more than in the past.

But the impact of weed on a fetus is not yet clear. "We have no direct evidence yet of what the effects may be, if any, at any specific point in pregnancy," Volkow said. However, a baby's nervous system begins developing the third week of gestation, before many mothers even realize they're pregnant. "We would expect that the impacts of marijuana use by the mother on the fetus would start then," she added.

With little evidence to support or dissuade pregnant mothers from using cannabis, the decision is often a personal one. One mother, for instance, who suffered from "hyperemesis gravidarum," a condition causing her to throw up so much it would harm her hers or the baby, used cannabis to combat the nausea.

"Marijuana did help. Immensely," she told VICE. "I don't think I would have made it through without cannabis."

Throughout both the prenatal period and the early years of life, the brain is continuously developing and may be influenced by the mother's own cannabis use during pregnancy or breastfeeding. As the brain forms new neurons, the baby's own endocannabinoid system (endogenous cannabinoid receptor cells throughout the body) is involved with those processes, according to Volkow. Hence, any cannabinoids from marijuana in the baby's system could have an affect.

"We do not yet know the degree of risk [for the fetus], but growing evidence suggests prenatal marijuana exposure may impact fetal brain development, which could have a lasting impact on the baby," she said. "Other effects for the baby include increased likelihood of anemia, lower birth weight, and increased risk of placement in a neonatal intensive care unit."

While the effects of cannabis on babies, both prenatal and in their infancy, are still hazy, some people support marijuana use during pregnancy as an alternative to alcohol and cigarettes. A 1994 study looking at newborns in Jamaica provides evidence that cannabis does not in fact have a truly deleterious effect on newborns.

So, with little evidence supporting both sides of the debate, mothers are left to their own discretion to decide whether or not to hit the vape.

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