Marijuana & Breastfeeding: Is it safe?

Author: Georgia Perinatal Association

Over half the country has legalized the medicinal and recreational use of marijuana. Georgia has yet to legalize the use of marijuana, yet many pregnant women use marijuana during pregnancy and breastfeeding. Marijuana is the most commonly used recreational drug used during pregnancy. Marijuana is classified as a scheduled 1 drug, which is in the same classification as cocaine. From 2009 to 2016, marijuana use has climbed from 4% to 9%. This data is self-reporting and thought to be higher than actually reported.

The Center for Disease Control and Prevention states that data data are insufficient to say yes or no on whether is it safe for mothers who use marijuana to breastfeed. Chemicals from marijuana in any form can be passed from mother to infant through breast milk.  The American Academy of Pediatrics (AAP) states thats present data are insufficient to assess the effects of maternal marijuana use on breastfeeding infants. Also, the AAP urges providers to inform mothers of the potential risks of marijuana during lactation, and to work with local health departments to help with constructive, non-punitive policy and education for families. The Academy of Breastfeeding Medicine states, “Breastfeeding mothers should be counseled to reduce or eliminate their use of marijuana to avoid exposing their infants to this substance and advised of the possible long term neurobehavioral effects from continued use.” The ACOG states there are insufficient data to evaluate the effects of marijuana use during lactation.

You can see why everyone is so confused on how the use of marijuana during lactation will affect infants. A research study was done in Colorado involving 8 postpartum women that smoked 0.1g cannabis;  breast milk was tested at 20 minutes, 1 hour, 2 hour, & 4 hours after cannabis consumption. D9-THC levels were detected in breast milk as early as 20 minutes and peaked at 1 hour. These data suggest that an exclusively breastfeeding infant ingests 2.5% of the maternal dose and demonstrates that D9-THC levels decline quickly in the breast milk compartment. By 4 hours after smoking, D9-THC levels were much lower. So, what does this mean?  After smoking 0.1mg of cannabis, the psychoactive molecule D9-THC enters the breast milk compartment rapidly, peaks at 1 hour, and is returning to baseline by 4 hours after consumption. D9-THC does not linger in breast milk due to its high fat content. More research is needed on the effects of marijuana on breast milk. This pilot data suggests that, like alcohol, there may be a day where is it possible to talk to lactating parents about the peak and fall of D9-THC exposure via human milk after smoking cannabis.

For now, marijuana continues to be classified as a L4, which means potentially hazardous per Dr. Hale’s Medications and Mother’s Milk (2019). With the legalization of cannabis/marijuana in many states, there is increased concern with use of marijuana in breastfeeding mothers. Both human and animal studies suggest that early exposure to cannabis may not be benign, and that cannabis exposure in the perinatal periods may produce long term changes in mental and motor development. While this data poses numerous limitations, and does not directly examine the benefits of breast milk vs exposure to marijuana in the milk, cannabis use by breastfeeding mothers should be discouraged at this time.


  1. Hale, Thomas (2019), Dr. Hale’s Medications and Mother’s Milk. New York: Springer Publishing Company
  2. Thompson, Heather. (2018) Publication of Colorado data!! Transfer of Inhaled Cannabis Into Human Breast Milk. Retrieved on May 24, 2019 from