With many states now moving forward with the legalization of medical marijuana, there seems to be a growing sense that marijuana is relatively safe and may, in some cases, be more attractive or effective than traditional pharmacologic interventions.  The use of marijuana in the United States appears to be increasing.  According to a nationwide survey, 7.3% of Americans 12 or older regularly used marijuana in 2012, up from 5.8% of Americans in 2007.  Among younger and socioeconomically disadvantaged women, the rates of use increase to 15  to 28 percent.

The majority of marijuana users are young and of reproductive age. It is estimated that  roughly half of female marijuana users continue to use during pregnancy.  While marijuana is often considered to be a relatively benign substance, we have data to indicate that the developing fetus may be particularly vulnerable to its effects.

The American College of Obstetricians and Gynecologists (ACOG) has issued a committee opinion on the use of marijuana in pregnant and nursing women, calling for ob-gyns to urge their patients who are pregnant or contemplating pregnancy to discontinue marijuana use.

This opinion reflects data indicating a spectrum of risks to the fetus related to maternal marijuana use.  (We have reviewed these findings in previous posts here and here.) These include:

  • Increased risk of intrauterine growth restriction
  • Low birth weight
  • Increased risk of stillbirth
  • Cognitive delays and deficits, poor executive functioning

Also concerning is that a growing number of people who view marijuana as a more attractive or effective option  than traditional pharmacologic interventions for the treatment of a variety of conditions, including nausea and vomiting, depression, and anxiety.  At this point, there is no data to support the use of marijuana for the management of these symptoms.  (This review published last week in JAMA reviews clinical studies using marijuana.)  ACOG recommends that pregnant women or women contemplating pregnancy should be counseled  to discontinue use of marijuana for medicinal purposes in favor of an alternative therapy for which there are better data regarding reproductive safety.

Ruta Nonacs, MD PhD

Marijuana Use During Pregnancy and Lactation (ACOG)