Understanding Cannabis Metabolism:

Before diving into the topic, it's essential to comprehend how cannabis is metabolized in the body. When cannabis is smoked or ingested, the active compounds (such as THC) enter the bloodstream and eventually pass into breastmilk. However, the timing and dosage play a crucial role in determining the concentration levels in breastmilk.

The THC transfer rate to breastmilk is about 2.5%, which might not seem like much. But if you're wondering how much of that actually reaches the baby's system, it's probably even less than 2.5%. Here's why: moms inhale, babies ingest, and that makes a big difference because it affects how much of the THC actually gets into their bloodstream. Also, it's good to know that the theoretical "level of concern" is set at over 10%.

“Hard to believe, but there is only one study (!) in which two samples (!) of human breast milk were analyzed.3 The two mothers were heavy users and their milk showed THC levels of 105 ng/ml and 340 ng/ml.4

Those two data points are interesting, but don’t answer the question how much THC makes it into breast milk because:

1. We don’t know how much marijuana was initially consumed.

2. We don’t know how long since the last marijuana consumption.

3. With a one-time measurement we don’t see how the THC concentration in breast milk behaves over 24 hours.

Both mothers were heavy users who were consuming marijuana on a daily basis. With regular use, THC accumulates in the body over time, especially in fat. And there is a lot of fat in breast milk. We don’t know which part of the detected THC is due to accumulation and which part is recently consumed THC.

A sample size of two isn’t representative for a larger population.

Here are the claims actually supported by science:

1. THC blood levels have proven to be highly variable across subjects.

2. THC blood levels drop soon after consumption because THC is rapidly taken up by fat tissue. It’s plausible therefore that THC levels would be higher in milk because of its high fat content.”

Debunking the Fear:

Contrary to some misconceptions, reputable studies have shown that if cannabis is consumed responsibly, it may not significantly impact breastmilk composition. Research suggests that waiting approximately 4 hours after consumption before breastfeeding can help minimize the presence of THC in breastmilk. Additionally, low levels of THC in breastmilk may not pose serious risks to infants and is often measured in nanograms.

When looking at any studies, it’s important to look for certain things and ask certain questions.
Was the cannabis quantity, quality, consumption method, and frequency documented in the study?
Were other factors considered? i.e. Alcohol use, other drug use, prescription medicine, nicotine, etc.
Who paid for the study?
Was synthetic cannabis used?

Responsible Cannabis Use and Breastfeeding:

It's crucial to avoid smoking cannabis in the presence of your baby. Equally important is not consuming excessive amounts that could impair your ability to provide proper care for your child. Prioritizing their safety and well-being means making responsible choices to ensure you remain fully attentive and capable of meeting their needs.

Frequently Asked Questions:

Can I use cannabis while breastfeeding?

It's important to remember that every individual's situation is unique, and what works for one person might not be suitable for another. When it comes to using cannabis while breastfeeding, it's a personal decision. It's important to consider the available information about potential risks. Ultimately, the choice should be one that feels right for you, your baby, and your overall well-being.

Will using cannabis affect the quantity of my milk? 

There is no conclusive evidence on this. 

Can cannabis pass into breast milk? 

Yes. The THC transfer rate to breastmilk is about 2.5%. But if you're wondering how much of that actually reaches the baby's system, it's even less than 2.5%. Here's why: moms inhale, babies ingest, and that makes a big difference because it affects how much of the THC actually gets into their bloodstream. Also, it's good to know that the theoretical "level of concern", when looking at medications in breastmilk, is set at over 10%.

What are the potential risks of cannabis exposure to my breastfeeding baby?

“One study8 from 1985 found no effects. The other identified slightly reduced motor development in kids of frequent users.9 That was only true if the mother consumed cannabis in the first month after birth and more frequently than 15 days per month. At one year old, those kids scored more poorly than the kids of non-users.10 However, those results can’t be distinguished from cannabis use during pregnancy; 84% of the mothers who used cannabis while breastfeeding had done so during pregnancy too.11” ref:https://sapiensoup.com/cannabis-breastfeeding#fn:astley

How long does cannabis stay in breastmilk?

Studies have shown that cannabis is most present in the breast milk after inhalation at one hour and tapers down to minute levels at four hours after consumption. Edibles have even lower THC levels.

This study looks at the amount of THC found in breastmilk after 1, 2, and 6 weeks. 

1 week 3.2 NG/mL 

2 weeks 5.5 NG/mL

6 weeks 1.9 NG/mL

(NG/mL = nanogram per milliliter)

Are there different forms of cannabis (e.g., smoking, edibles, oils) that have varying effects on breastfeeding?

Yes, different consumption methods transfer differently. Edibles have lower THC exposure. 

If I used cannabis during pregnancy, could that affect my breast milk differently?

There are no studies that we have come across that states cannabis affects breast milk differently other than the traces of THC within it. Anecdotal evidence may say differently. We’ve had mother’s share that consuming cannabis has allowed them to relax enough that their supply has increased and we’ve had others share that consuming cannabis led to a burning let down while nursing. It affects everyone differently, just as any medication has different effects on individuals.

Are there legal considerations I should be aware of when using cannabis while breastfeeding?

Every state has their own laws surrounding cannabis and pregnancy. It is always recommended to educate yourself on your state laws before choosing to consume.

What resources are available for parents who want more information about cannabis and breastfeeding?

Things like this blog post and the ones we’ve referenced in this article can be helpful. Another thing you can do is look at the studies linked to the information offered in blog posts and articles. You can also seek out resources from trusted cannabis educators.

Is it safe to pump and store breast milk if I've used cannabis? 

Yes. We recommend pumping before you consume your cannabis or immediately after as the peak concentration is from 1-3 hours after consumption. No need to pump and dump!

Should I adjust my cannabis use based on my baby's feeding schedule? 

Studies show that the amount of cannabis within your breastmilk changes based on the consumption method, dosage, and time span after consumption. We recommend feeding your baby before consuming your dose of cannabis and waiting at least four hours before feeding again.

Are there any potential long-term effects of cannabis exposure during breastfeeding that we should be concerned about?

There are not enough studies to determine whether or not cannabis exposure in breastmilk has long-term effects.

Supporting Breastfeeding Mothers:

We understand that every parent's journey is unique. Some may choose to abstain from cannabis entirely during breastfeeding, while others may make informed decisions to balance their well-being and parenting responsibilities. Our goal is to support all parents on their breastfeeding journey while providing accurate information.

At Momentous Doula Care, we believe that education is empowering. When it comes to cannabis and breastfeeding, knowledge can dispel fears and foster responsible choices. Understanding that the concentration of cannabis in breastmilk can be minimized with proper timing and dosage can reassure breastfeeding parents who choose to use cannabis.

Remember, every parent's journey is unique, and we are here to provide support and information to help you make the best choices for yourself and your baby. Together, let's embrace knowledge and create a nurturing environment for motherhood and beyond.

Disclaimer: The information provided on this website is intended for educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your healthcare provider with any questions you may have regarding a medical condition. Additionally, the views and opinions expressed on this website are solely those of the original authors and other contributors. These views and opinions do not necessarily represent those of Momentous Doula Care.

References:
(1) Cannabis and Breastfeeding: The Facts
(2) Persistence of Δ-9-Tetrahydrocannabinol in Human Breast Milk
(3) How States Handle Drug Use During Pregnancy
(4) Baker, T., Datta, P., Rewers-Felkins, K., Thompson, H., Kallem, R. R., & Hale, T. W. (2018). Transfer of inhaled cannabis into human milk. Obstetrics & Gynecology, 131, 783-780.
(5) Bertrand, K. A., Hanan, N. J., Honerkamp-Smith, G., Best, B. M., & Chambers, C. D. (2018). Marijuana use by breastfeeding mothers and cannabinoid concentrations in breast milk. Pediatrics, 142(3), e20181076.