On Monday, January 11, 2017, The American Medical Association released two updates on marijuana use in pregnancy and the results are both interesting and concerning. In the past decade, marijuana use in the United States has increased. Between 2001 and 2013, the rate of marijuana use in adults in the United States has more than doubled. 29 states and Washington D.C. have legalized medical marijuana and others have legalized the recreational use of the drug. There is limited evidence that marijuana may be helpful in a handful of medical situations, but as a whole, the subject of marijuana in medical applications has not been widely studied.
In the U.S.,
- 7.6% of nonpregnant reproductive age females reported marijuana use in the past month during the study period of 2007-2012.
- 3.9% of pregnant people between the ages of 18 and 44 reported using marijuana within the past thirty days in a 2014 survey, up from 2.37% in 2002. This is an increase of 62%.
- Amongst the age group of pregnant 18-25 year olds, 7.5% of pregnant people had used marijuana in the past 30 days.
- Past year use was 11.6% amongst currently pregnant 18-44 year olds.
There is some evidence from both animal and human studies that prenatal exposure to marijuana may be linked to poor outcomes. Babies born to people who used marijuana were more likely to have a low birth weight, be anemic, need NICU care at birth and suffer from impaired neurological development, and impaired higher order executive functions such as impulse control, visual memory and attention issues during their school years. There is an ongoing prospective study, that has found an association between prenatal cannabis exposure and fetal growth restriction during pregnancy and increased frontal cortical thickness among school-aged children.
As a result of these relationships, health care providers are urged to counsel pregnant people and those considering becoming pregnant to abstain from using marijuana. Additionally, there is a correlation between marijuana use and alcohol and other drug use at the same time, which also can impact the developing baby.
A systematic review and meta-analysis found low quality evidence that some derivatives of marijuana may be effective in the prevention of nausea for people undergoing chemotherapy. Nausea is a medically approved indication for marijuana in all states where medical use of this drug has been legalized.
Recent investigation indicates that some pregnant people are choosing to utilize cannabinoid products to help with the "morning sickness" that frequently accompanies the first trimester of pregnancy, and continue beyond that in some cases including in cases of Hyperemesis Gravidarum (severe morning sickness that typically requires medical treatment.) First trimester marijuana use is of great concern due to the possibility of serious and potentially lifelong negative consequences on the developing embryo. Pregnancy data from Hawaii indicated that women with severe nausea during pregnancy were more likely to use marijuana, compared with other pregnant women (3.7% vs 2.3%, respectively).
Health care providers should not recommend marijuana as a treatment for nausea in pregnancy and should discourage recreational use as well. In 2015, the American College of Obstetricians and Gynecologists (ACOG) issued a committee opinion discouraging physicians from suggesting use of marijuana during preconception, pregnancy, and lactation.
Is the increase in pregnant people using marijuana a result of the increase in the number of states that have legalized medical marijuana? Is it a result of some states making marijuana legal in small amounts for recreational use, and it therefore is more accessible to everyone, including people suffering from morning sickness during pregnancy? There are no states that specifically list pregnancy-related conditions among the allowed recommendations for medical marijuana. Medical marijuana is not required to include warnings about the possible harms of marijuana to the fetus when the drug is used during pregnancy.
Why has the percentage of pregnant people using marijuana increased? Although the prevalence of past-month use among pregnant women (3.9%) is not high, the increases over time (2002-2014) and potential adverse consequences of prenatal marijuana exposure indicate that additional research is necessary.
Does the topic of marijuana use come up during your childbirth classes? Do families have questions about its use for morning sickness, pain relief or during lactation? How do you respond to these inquiries? I live in Washington state and we have had legal medical marijuana for several years and legal recreational marijuana use permitted for the last few years. Not a class goes by that this topic is not brought up by the families I work with. It is clear that use of marijuana products by pregnant people is on the rise. We would be remiss as educators and other professionals who work with people during the childbearing year, if we were not ready to answer their questions by sharing what we know, which is limited for sure. As you can imagine, it is not easy to obtain valid research on this topic, when there is the potential for harm to the fetus, newborn and child from marijuana by a pregnant parent during pregnancy.
American College of Obstetricians and Gynecologists. (2015). Committee Opinion, Marijuana use during pregnancy and lactation.# 637.
Brown, Q. L., Sarvet, A. L., Shmulewitz, D., Martins, S. S., Wall, M. M., & Hasin, D. S. (2016). Trends in Marijuana Use Among Pregnant and Nonpregnant Reproductive-Aged Women, 2002-2014. JAMA.
Volkow ND, Compton WM, Wargo EM. The Risks of Marijuana Use During Pregnancy. JAMA.2017;317(2):129-130. doi:10.1001/jama.2016.18612