Medically Reviewed by
Jason Crawford

Article Last Updated on December 28, 2022

Some of the most commonly discussed topics regarding weed are its recreational effects and its medical benefits. But, considering how many more people smoke weed nowadays because it’s more readily available in an increasing number of states, one less discussed topic is how weed can affect breastfed babies.

Many mothers use cannabis either to relax or to alleviate some medical conditions, and many also wonder if it’s safe for the baby to smoke weed while they’re breastfeeding. We already talked about the presence of weed in the placenta, and now it’s time to talk about the weed in breast milk. 

In this article, we’ll talk about whether breastfeeding mothers can still smoke weed during lactation and if it’s harmful to the baby, so let’s get started.

The Benefits of Breastfeeding for the Baby

Breast milk is incredibly beneficial for babies as it’s considered to be the optimal nutritional option for the first months of their lives. The general recommendation for breastfeeding mothers is to breastfeed their babies for about six months. 

Breastfed babies have a lower risk for developing infections due to the presence of antibodies which can help to fight off bacteria and viruses. Feeding your baby with breast milk also reduces the risk of sudden infant death syndrome (SIDS), obesity, diabetes and cardiovascular disease in adulthood, as well as gastrointestinal infections.

Breastfeeding is also beneficial for the mothers. It’s thought to help reduce the risk of developing high blood pressure, type 2 diabetes, and heart disease.

But what happens when we put marijuana use in the picture? Can nursing mothers still smoke weed while breastfeeding and are there any potential risks for the baby?

Is Cannabis Present In Human Breast Milk?

The cannabis plant contains hundreds of compounds, of which the cannabinoids are the most abundant. The two most prominent cannabinoids are THC (tetrahydrocannabinol), the cannabinoid that gets you high, and CBD (cannabidiol), which has therapeutic effects.

When the cannabinoids are processed by the body upon consumption, they get turned into byproducts that remain in the body fat for days or weeks. Cannabinoids seek fat because they are fat-soluble and depending on how frequently you smoke, they can remain in your body for days or weeks.

One way that cannabis is thought to reach breast milk is by the fat cells which are used by the body in milk production, and the other way is through the blood vessels in the breast tissues which have access to the milk ducts.

In fact, a 2018 clinical study has found the presence of THC in the breast milk of nursing mothers who were also regular marijuana users. They participated in the study by donating samples of their breast milk to be tested for THC. The results showed that low levels of THC were found in the samples.

How Long Does Cannabis Stay In Mother’s Milk?

There is definitely a lack of research regarding cannabis and breastfeeding, but the small number of studies that have been conducted in recent years have been qualitative and have given us some insight.

A 2018 longitudinal study found that traces of THC can be detected in breast milk samples about six days after use. However, a newer study published in 2020, discovered that THC can remain in the breast milk of regular cannabis users for up to six weeks after abstinence.

Should Breastfeeding Moms Smoke Weed?

Seeing as how common cannabis use is nowadays, it’s very important to address this question. Cannabis may have many health benefits, but we still don’t know how it can affect babies and whether it could cause negative effects on their development due to its psychoactive properties. Newborns are highly vulnerable during the first months of their lives, and in theory, marijuana exposure could pose some health risks. 

Therefore, a pressing question is whether breastfeeding mothers should smoke weed during lactation. What does science has to say so far? Let’s see!

Marijuana Use During Lactation Could Harm the Baby’s Development

A 2018 article on marijuana use during pregnancy and lactation suggests that smoking weed while breastfeeding can harm the baby’s development in multiple ways. It seems that the use of marijuana can negatively impact the baby’s motor development and even cause congenital defects.

Similarly, the FDA (Food and Drug Administration) states that cannabis may affect brain development which could result in neurobehavioral problems and poor cognitive function later in life, and they strongly advise mothers against smoking weed during lactation.

Using Cannabis While Breastfeeding Could Affect Milk Production

Some older studies have discovered that smoking weed can tamper with milk production and hormone levels. One 1985 study found that chronic cannabis use can lower the levels of prolactin, an important hormone involved in milk production.

Secondhand Smoke Can Be Extremely Harmful to the Baby

Secondhand smoke is harmful in itself since it contains many of the same toxins as tobacco smoke, but when it comes to infants, its side effects can be a lot more harmful (especially if the mother mixes the weed with tobacco). 

The Academy of Breastfeeding Medicine (ABM) wrote in their 2015 Guidelines for Breastfeeding and Substance Use or Substance Use Disorder that exposure to secondhand smoke doubles the risk of sudden infant death syndrome (SIDS) in breastfed babies.

Smoking Weed During Lactation Can Impair a Mother’s Ability to Care for Her Baby

The ABM also warns about the mother’s ability to appropriately care for her child while under the influence of weed. They stress that her ability to respond to her baby’s needs may be significantly impaired when smoking weed, which could put the baby in danger. 

What About Medical Marijuana?

Some breastfeeding women may use marijuana for medical purposes, and this is also a grey area. Needless to say, if you want to continue using marijuana you should consult with your healthcare provider and get counseling on how to use marijuana during this time.

The CDC (Centers for Disease Control and Prevention) suggests that if a mother wants to continue using marijuana during the lactation period, she should “be encouraged to significantly reduce her intake” as well as avoid smoking marijuana around her child in order to minimize the exposure to secondhand smoke.

Final Thoughts – Should You Smoke Weed While Breastfeeding?

While marijuana has its benefits, it’s still unclear what its effects on newborns are and whether it poses any health risks. It’s also unclear whether the benefits of breastfeeding override the potential risks of marijuana presence in breast milk. 

There is definitely a lack of studies on the subject, but all of the authoritative bodies advise against it simply because it’s better to stay on the safe side. Cannabis, or THC, in particular, affects the brain in more ways than one, and this can be a serious risk for newborns whose bodies and brains are only beginning to develop. 

As the CDC advises: “To limit potential risk to the infant, breastfeeding mothers should be advised not to use marijuana or marijuana-containing products in any form, including those containing CBD, while breastfeeding.”

Additional Sources

Ryan, S. A. (2018). Marijuana use during pregnancy and breastfeeding: Implications for neonatal and childhood outcomes. American Academy of Pediatrics. https://publications.aap.org/pediatrics/article/142/3/e20181889/38625/Marijuana-Use-During-Pregnancy-and-Breastfeeding

A passionate advocate for the benefits of cannabis. Fraser Horton, who has a background in botany and a strong love of nature, has spent years researching how cannabis affects the body and mind. He established Leaf Nation in 2020, where he has devoted himself to educating people about the legalisation of marijuana and its safe and responsible use. Fraser is committed to highlighting cannabis’ potential for improving wellness and working to dispel the stigma associated with its use.


The information presented on this page is provided as a public service to aid in education and is derived from sources believed to be reliable. Readers are responsible for making their own assessment of the topics discussed here. In no event shall Leaf Nation be held reliable for any injury, loss or damage that could happen if using or abusing drugs.