How Long Does THC Stay in Breastmilk?

As cannabis reform spreads across the United States, more people feel ready to experiment with cannabis or step out into the public about their usage. A growing number of cannabis consumers are parents. However, many parents have questions about how marijuana consumption might affect their role as parents. One such concern revolves around the possible effects cannabis use may have on breast milk and breastfeeding.

Breastfeeding can play an important role in many parents' child-rearing plans, and it can affect many of the decisions a breastfeeding parent makes (avoiding certain foods, drinks, and medications, for example). But is there actually a danger in using cannabis while nursing a newborn?

With a lack of definitive answers at this time, it's only natural that parents continue to voice their concerns and ask questions like, “How long does THC stay in breast milk?”

While many consumers assert that cannabis use is safe, adverse effects are still a reality that some users will face. With the possible effects on their child's health and well-being, parents may want to exercise extra caution until researchers better understand how long THC stays in breast milk and what effect it may have on nursing babies.

Can THC Get Into Breastmilk? 

Yes, traces of THC have been found in breast milk. 

Clinical studies remain scant to date, with few subjects tested in most analyses. One study found that the amount of THC in pumped breast milk varied, with researchers concluding that an average infant dose amounted to 8 micrograms per kilogram of THC consumed daily.¹

Another 2018 study conducted by UC San Diego seems to support these findings. The study analyzed breast milk samples from 54 women between 2014 and 2017. Researchers noted that THC levels were “highly variable” in subjects. The examination found that 63% of breast milk samples contained detectable amounts of THC for up to six days. The average concentration in the analysis was 9.47 nanograms of THC per milliliter of breast milk.²

While these studies indicate that THC can make its way into breastmilk of nursing parents, we still lack answers to a few important questions:

• How long do cannabinoids stay in breast milk?
• How does the presence of THC affect breast milk or the nursing child?

It also isn’t clear exactly how much THC passes into breast milk. However, we do recognize some of the factors that likely play a role, including the amount and frequency of cannabis consumed, the product’s potency, and the parent’s metabolism.

How Long Does THC Stay in Breastmilk?

With the lack of research available, it remains unclear how long THC stays in breast milk. According to one small study in JAMA Pediatrics, THC can be excreted in the breast milk of regular consumers for up to six weeks after stopping their use.³

But we also know that cannabis metabolizes at different rates in the body. With such a small sample size (just seven participants), additional research is required before making any definitive statements about how long THC stays in the breast milk of nursing parents.

Without clear answers, some parents are searching for workarounds. 

The “pump-and-dump” method is when a parent extracts breast milk and disposes of it rather than giving it to their baby. This approach has been used by some cannabis-consuming moms operating under the assumption that they’re eliminating the milk that had absorbed the THC compounds, and any new milk will be clear of cannabinoids. However, one study suggested that THC can remain in bodily fluids for up to 30 days, so the pump-and-dump approach may not be as effective as some parents think.⁴

We still need more research to determine exactly how long THC stays in breast milk and what, if anything, parents can do to eliminate it quickly. For now, groups like The American Academy of Pediatrics recommend that parents avoid cannabis consumption during pregnancy and while breastfeeding. Some lactation specialists offer more liberal guidelines, suggesting that the amount of cannabis consumed may play a part in whether a parent should abstain from cannabis during pregnancy and breastfeeding.¹

At this time, parents should consult with trusted medical professionals. Even then, it is worth remembering that this field of study is only in its infancy (no pun intended).

Can I Breastfeed While Using Cannabis? 

Without enough evidence to support a clear answer, many professionals are erring on the side of caution and advising parents that it may be best to avoid consuming cannabis while pregnant or breastfeeding.

Still, many parents are not ready or able (in the case of some medical cannabis patients) to give up cannabis during this long period. As a result, some parents are turning to different cannabinoids like cannabidiol (CBD). 

CBD is known as the non-intoxicating cannabinoid used by many medical marijuana patients. It has been noted as a source of potential relief, including physical and mental alleviation. And early scientific studies on the benefits of CBD have led some parents to switch to CBD-dominant or CBD-only options while planning their family and feeding their newborns.

However, the effects of CBD on breast milk and infants remain just as unclear as THC. As a result, most pediatric groups continue to recommend that parents abstain from cannabis while breastfeeding, regardless of the specific product. 

Conclusion 

This subject will continue to evolve as additional research is made public. For now, the choice is ultimately up to the breastfeeding parent, and it is worth taking time to understand the latest clinical data and consult with medical professionals whenever possible.

Resources

1. Metz TD, Borgelt LM. Marijuana Use in Pregnancy and While Breastfeeding. Obstet Gynecol. 2018;132(5):1198-1210. doi:10.1097/AOG.0000000000002878 ↩︎
2. Bertrand KA, Hanan NJ, Honerkamp-Smith G, Best BM, Chambers CD. Marijuana Use by Breastfeeding Mothers and Cannabinoid Concentrations in Breast Milk. Pediatrics. 2018;142(3):e20181076. doi:10.1542/peds.2018-1076 ↩︎
3. Wymore EM, Palmer C, Wang GS, et al. Persistence of Δ-9-Tetrahydrocannabinol in Human Breast Milk. JAMA Pediatr. 2021;175(6):632-634. doi:10.1001/jamapediatrics.2020.6098 ↩︎
4. Hadland SE, Levy S. Objective Testing: Urine and Other Drug Tests. Child Adolesc Psychiatr Clin N Am. 2016;25(3):549-565. doi:10.1016/j.chc.2016.02.005 ↩︎

The information in this article and any included images or charts are for educational purposes only. This information is neither a substitute for, nor does it replace, professional legal advice or medical advice, diagnosis, or treatment. If you have any concerns or questions about laws, regulations, or your health, you should always consult with an attorney, physician or other licensed professional.