Researchers examining marijuana in the breast milk of nursing mothers measure the number of cannabinoids in breast milk after marijuana use.
There has been a surge in the number of individuals engaging in the use of medicinal and recreational marijuana, probably due to an increase in availability and accessibility following its legalization.
Marijuana is quickly becoming the most recreational drug of abuse among pregnant women and breastfeeding mothers, increasing the need for research regarding marijuana in breast milk. For example:
Is marijuana present in the breast milk of breastfeeding mothers? At what concentrations? How long does THC or other cannabinoids stay in breast milk?Â
Breastmilk has numerous health benefits for the baby and it is strongly recommended for mothers to exclusively breastfeed their infants for the first six months of life.
Therefore, it is important to know of any potential health risks of using marijuana and its effects on breast milk.
Marijuana, otherwise known as cannabis, contains psychoactive components called cannabinoids. Cannabinoids (tetrahydrocannabinol, cannabinol, and cannabidiol) are known to have some effects on the brain.
They also attach to fat molecules, which are abundant in breast milk.
Marijuana in breastmilk found up to six days after last use
In a study published in the journal Pediatrics, researchers examined 54 samples from 50 breastfeeding mothers who had provided their samples to a research repository called Mommy’s Milk.
The researchers performed an analysis using liquid chromatography-mass spectrometry electrospray ionization, which revealed various concentrations of the different types of cannabinoid tetrahydrocannabinol (THC), cannabinol, and cannabidiol.
The researchers detected tetrahydrocannabinol (THC) in 63% of the samples up to six days after the mothers’ last marijuana use. They found cannabidiol in 9% of the samples. They did not detect any cannabinol.
Some samples were not collected under direct observation and the researchers depended on online questionnaires and interviews to determine the mothers’ exposure to marijuana.
However, this study does use a relatively large number of samples, and, participants were professionally guided on how and when to collect the samples.
Again, the findings in this study are consistent with other research that has demonstrated a high concentration of cannabinoids, especially THC, in breast milk.
They specifically found these concentrations six days after the last marijuana use.
The study aligns with previous findings on marijuana in breast milk
A previous study found that the more marijuana a mother smoked, the higher concentrations of marijuana they found in the milk sample. Marijuana is also more concentrated in breast milk than in the blood.
Another study found that the infant’s stool had a higher concentration of marijuana than the mother’s milk following ingestion, demonstrating that the infant sucked, absorbed, and digested the marijuana.
A study tracking the levels of THC in breastmilk reported not only that THC was present in breastmilk, but also estimated that the infant ingested 2.5% of the amount that was initially ingested by the mother.
In terms of effects on infants, neurodevelopmental deficits in infants who were exposed to marijuana have been documented, however, this is not consistent among studies.
More studies are needed to determine the effect of marijuana on babies exposed to breastmilk
Based on the presence of a detectable, measurable amount of marijuana found in these studies, coupled with the previous studies documenting psychomotor deficits and neurodevelopment effects in babies exposed to marijuana through breastmilk, researchers recommend that more studies are urgently needed investigating the effect of marijuana on nursing babies.
Meanwhile, based on existing evidence regarding the amounts and how long marijuana stays in breast milk, health professionals strongly advise against the use of marijuana by pregnant women and nursing mothers.
Written by Ijeoma C. Izundu, MBBS
Updated Dec 2020
References:
- Bertrand K, Hanan N, Honerkamp-Smith G, Best B, Chambers C. Marijuana Use by Breastfeeding Mothers and Cannabinoid Concentrations in Breast Milk. Pediatrics. 2018;142(3):e20181076.
- Marijuana is found in breast milk up to six days after use [Internet]. EurekAlert! 2018 {cited 2 October 2018]. https://www.eurekalert.org/pub_releases/2018-08/uoc–mfi082318.php
- Baker T, Datta P, Rewers-Felkins K, Thompson H, Kallem RR, Hale TW. Transfer of Inhaled Cannabis Into Human Breast Milk. Obstet Gynecol. 2018 May;131(5):783-788. doi: 10.1097/AOG.0000000000002575. PMID: 29630019.
Other topics that may be of interest:
- Do marijuana edibles harm patients with heart disease?
- Marijuana-related poison control center phone calls before and after legalization
- Does parents’ marijuana use increase the risk of substance use by their kids?
- Marijuana use in teens may reduce ability to cope with stress in adulthood
- What are the combined effects of marijuana and stress in teenagers?
