Motherhood and Marijuana

With the legalization of marijuana for medical and recreational use in Vermont and other states, I thought this week I would smoke out some concerns about its use in pregnant mothers, and mothers who breastfeed.

Recently the American Academy of Pediatrics (AAP) issued a clinical report on the implications for infants and children of marijuana use during pregnancy and breastfeeding.  Their conclusion in the report is that no amount of marijuana has been proven safe to use during pregnancy or while breastfeeding.

Why does the report say this?  Tetrahydrocannabinol or THC is the compound in marijuana mostly responsible for its psychoactive effects.  THC can cross into an infant via the placenta during pregnancy and after birth through breastmilk.  Once in the baby’s system, it can affect nerve cell growth and in turn potentially affect the developing brain in an abnormal way. Babies born to mothers who use marijuana during pregnancy have been found to have poor sleep patterns, are easily startled and agitated and in childhood show an increased risk of hyperactivity, inattention, as well as problems with memory and impulsivity.

Marijuana use during pregnancy can increase carbon dioxide levels 5 times higher than when tobacco is smoked, meaning less oxygen as the baby grows and develops which can potentially trigger growth issues, premature birth, possible birth defects, miscarriage, and stillbirth.

So what do the AAP as well as I recommend?  Given the lack of definitive research on the benefits of marijuana for pregnancy or with breastfeeding, don’t use marijuana when pregnant or even thinking about becoming pregnant.    If the thought is it will help calm the nausea of morning sickness, the safety of doing this has never been well-studied, and the risks are likely to far outweigh the benefits. In addition, a mother’s ability to care for their infant once born may be hampered or impaired by their use of marijuana, putting a child at risk for harm which is an event potentially reportable to the Department of Children and Families.

Hopefully, tips like these will provide some highlights to keep in mind when it comes to learning as much as we can about the potentially harmful effects of marijuana during pregnancy and with breastfeeding.

Lewis First, MD, is chief of Pediatrics at The University of Vermont Children’s Hospital and chair of the Department of Pediatrics at the University of Vermont College of Medicine.  You can also catch “First with Kids” weekly on WOKO 98.9FM and WPTZ Channel 5, or visit the First with Kids video archives at

 Stay Informed

Sign up to receive the latest stories, information and guidance from our experts on a wide variety of health topics.