Marijuana is becoming a legal drug in more states each year (23 states the District of Columbia have legalized it in some form). My state, Oregon, became the most recent addition to that list on July 1st.
Talking with a labor and delivery nurse in my local hospital yesterday, I learned the policies in her unit are changing too. More mothers are admitting to using marijuana during pregnancy and the nurses no longer collect a newborn’s urine for the drug. The common reasons for smoking marijuana during pregnancy are relief from nausea and anxiety. These are very real and debilitating problems that often continue after delivery and into the breastfeeding period.
But the safety of smoking marijuana during breastfeeding has not been proven. In fact, the available data raises serious concerns about the effects of marijuana use by lactating women.
THC is excreted in breast milk in moderate amounts and babies can excrete it in their urine for 2-3 weeks after ingestion. A fat-soluble drug, THC is transferred to the baby through the fat in breast milk. A study published in 1998 reported infants exposed to marijuana via breast milk show signs of sedation, reduced muscular tone, and poor sucking coordination. Another study showed no differences between babies that have been exposed to marijuana through breast milk and those that had not. Often, this conflicting data can be the result of outside factors which are difficult to control for during a study.
However, the available data was examined by the American Academy of Pediatrics (APA), they recommend strongly against using marijuana if a mother is breastfeeding. During the first months of life an infant’s brain is undergoing rapid growth and the APA cites concerns about negative effects on brain development.
While there are no studies of the long-term effects of THC ingestion during infancy, the preponderance of evidence supports passing on pot while breastfeeding.
Garry, A., Rigourd, V., et al. (2009). Cannabis and Breastfeeding. J Toxicol. 2009; 2009: 596149.
Published online 2009 Apr 29. doi: 10.1155/2009/596149
Behr, T., (2015). Marijuana and Breastfeeding. http://www.breastfeeding-problems.com/marijuana-