Avoid cannabis while breastfeeding
Cannabis and breastfeeding: https://pubmed.ncbi.nlm.nih.gov/33469174/
The THC concentration in breast milk is on average 7x the concentration of THC in mom’s blood. This is part of why most medical groups recommend avoiding cannabis while breastfeeding.
I’m Dr. Wagner, a board certified pediatrician. I made a video a few days ago about how the alcohol concentration in mom’s blood is about the same as in breast milk, and this is unfortunately NOT the case for THC.
This 2021 study followed twenty breastfeeding moms by measuring the THC and CBD concentrations in their serum (blood) and breast milk who were self-reported cannabis users at 2 weeks and 2 months post-partum. These moms were frequent users who increased their use from birth to two months – an average of 17 times/week in the first two weeks and 23 times/week at 2 months. Concentration in blood of THC was on average 3.7 ng/dL, and in breast milk in 27.5 ng/dL, (generally the higher in blood the higher in breast milk) more than 7 times the concentration in the maternal blood (this is in contrast to ALCOHOL in breast milk, which is about equal to the quantity in maternal blood). CBD also concentrates in breast milk, though not as dramatically as THC. Prof Emily Oster did the full math for this one to calculate that if breastfeeding at peak levels of THC, the infant would reach approximately ⅓ of mom’s weight adjusted dose of THC. This is in contrast (this is my rough math, not perfect) to the alcohol numbers I talked about last week, where after one drink that baby is breastfeeding at peak alcohol levels, is at about 1% of mom’s weight adjusted dose. I bring this up because in another small study 80% of moms who use marijuana while breastfeeding do NOT report any concerns about cannabis while breastfeeding, and We don’t have enough data on the long-term implications of cannabis on the developing brain, and avoidance as much as possible of cannabis containing products while breastfeeding is strongly recommended.
(This is my math – 14g alcohol in one drink (0.2g/kg to 70kg mom)→ 0.03% alcohol in 90mL breast milk → 0.02g alcohol (0.0033g/kg in 6kg baby) → about 1% of mom’s weight-adjusted dose, <0.2% of maternal drink to baby)
