Marijuana in Breastmilk Has No Short-Term Effects, Study Shows

Premature baby drinking breastmilk from a bottle

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Key Takeaways

  • A study found that using marijuana while breastfeeding had no short-term health effects. 
  • The study does not provide enough evidence to say that marijuana use is safe while breastfeeding. 
  • Preterm babies benefit greatly from their parents’ breast milk.

Parents want to do what's best for their kids, which means giving their preemies the best shot at life that they can. However, since one of the active ingredients in marijuana--tetrahydrocannabinol (THC)--passes through the breastmilk, most healthcare providers refrain from giving THC-positive milk to preemies because they don't fully know what the effects might be.. However, since one of the active ingredients in marijuana--tetrahydrocannabinol (THC)--passes through the breastmilk, most healthcare providers refrain from giving THC-positive milk to preemies because they don't fully know what the effects might be.

A new small study from October 2021 found that marijuana use while breastfeeding preterm babies had no short-term health effects. The results of this study bring up the possibility that it may be worth it to give preterm infants their parents’ breast milk even if they used marijuana.

However, there is still not currently enough evidence to say that marijuana is safe while breastfeeding. For now, marijuana is still considered unsafe to use while breastfeeding, but additional research is warranted.

Details About the Study

Looking at the data on health issues like breathing difficulties, development, and feeding issues in 700+ infants between 2014 and 2020, babies fed breastmilk from mothers using THC had similar health outcomes to those whose mothers did not use THC. 

The study also split the 17% of infants whose mothers tested positive for THC at birth into two groups, those who breastfed and those who did not. There was no indication of THC use having any short-term negative effects on preterm infants. 

The researchers noted that parents who use THC tend not to seek prenatal care as early as is recommended. Lack of appropriate care during pregnancy may have negative effects for the baby, not caused directly by THC. 

Benefits of Breastmilk for Preterm Babies

The composition of breast milk changes to meet babies’ needs at different stages, and it has a unique composition when babies are born preterm to help them stay healthy. “Nursing mothers of preterm babies produce a different kind of milk than those who had a term baby,” explains Kecia Gaither, MD, MPH, FACOG, a double board-certified OBGYN, maternal-fetal medicine doctor, and director of Perinatal Services at NYC Health and Hospitals/Lincoln. 

Kecia Gaither, MD, MPH, FACOG

Nursing mothers of preterm babies produce a different kind of milk than those who had a term baby.

— Kecia Gaither, MD, MPH, FACOG

Preterm breast milk also reduces the risk of a life-threatening intestinal issue called necrotizing enterocolitis.

“Necrotizing enterocolitis is basically inflammation of the gastrointestinal tract that eventually leads to death of the tissue,” explains Krystyn Parks, MS, RD, a pediatric registered dietitian, and certified breastfeeding specialist. “Babies who end up with it often end up needing parts of their GI tract removed, which can have lasting complications. Using an exclusively human milk diet has been shown to decrease the incidence of necrotizing enterocolitis significantly.”

When babies are born early, breast milk has lots of protein and necessary minerals that help with things like brain growth, immunity, and organ development. Preemie breastmilk also contains lactoferrin, a protein that aids in digestion. "[Lactoferrin] improves babies' ability to absorb the nutrients in breastmilk," notes Dr. Gaither.

The composition of preterm breast milk is also specifically compatible with the premature baby’s gut, making intestinal infections less likely. “Preterm breast milk contains higher levels of epidermal growth factor (EGF)...which is distinctly needed for gut maturation and intestinal healing,” notes Dr. Gaither. 

Breastmilk aids in brain development, which is especially important for babies who are born early. Preterm babies also benefit from the high level of antibodies found in breast milk that is produced right after birth.

Often, babies who are born early cannot nurse well, so it is recommended to pump and give your baby your milk in a bottle from birth. This gives them the benefits of breastmilk while preserving your milk supply so that you can nurse or continue to pump and give your baby breast milk as they grow.

Can I Use Marijuana While Breastfeeding?

It is not recommended to use any form of marijuana at any stage of breastfeeding. The study provides some evidence to say that it’s possible that the benefits of breastmilk for preterm babies outweigh the risk of using marijuana while breastfeeding; however, there is not enough data to change the recommendation to avoid all forms of marijuana while breastfeeding. 

We do know that marijuana transfers through breastmilk, so there is reason to be concerned about its long-term effects on breastfeeding infants. If you choose to use marijuana, you should refrain from breastfeeding your baby.

More research is warranted to see whether preterm babies in the Neonatal Intensive Care Unit (NICU) should be given their parents’ breast milk even if these parents had used marijuana. Chemicals in marijuana may pass through breast milk and impact infants, emphasizes Dr. Gaither. “There doesn't exist enough research to give a green light to breastfeeding while using marijuana.”

What This Means For You

Giving birth prematurely can be scary. Preemies are more vulnerable than term babies. Know that breastfeeding a preterm baby offers many health and developmental benefits. If your baby struggles to nurse, as many premature babies will, it is recommended to pump your milk and feed it to your baby in a bottle. This will ensure that your baby gets the special benefits your milk can provide, and it allows you to keep your milk supply up for continued breastfeeding.

Marijuana use is currently not recommended while breastfeeding. If you use marijuana for physical or mental health reasons, it is advised to stop during the time that you are breastfeeding. If marijuana helps you function, it may be worth it to abstain from at least during the early weeks when your milk can really help your preemie thrive.

13 Sources
Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Elisa Cinelli
Elisa is a well-known parenting writer who is passionate about providing research-based content to help parents make the best decisions for their families. She has written for well-known sites including POPSUGAR and Scary Mommy, among others.