This sheet is about exposure to marijuana in pregnancy and while breastfeeding. This information should not take the place of medical care and advice from your healthcare provider.
What is marijuana?
Marijuana is made from a mix of dried flowers from the Cannabis sativa plant. Some other names for marijuana are pot, weed, or cannabis. There are several ways to use marijuana, including smoking or vaping (inhaling), eating or drinking products infused with marijuana (edibles), or as a preparation applied to the skin (topical). The main active chemical in marijuana is delta-9-tetrahydrocannabinol (THC), which is what gives people that “high” feeling.
Another major component of marijuana is cannabidiol (CBD). CBD can be found in many products such as coffee, chocolate, supplements, tinctures, cosmetics, lotions, suppositories, and bath salts. CBD products labeled as “THC free” might still contain a measurable amount of THC.
Professional organizations such as the American Academy of Pediatrics (AAP) and the American College of Obstetricians and Gynecologists (ACOG) advise that people who are pregnant avoid using marijuana. The U.S. Food and Drug Administration (FDA) advises against the use of CBD, THC, and marijuana in any form during pregnancy or while breastfeeding.
How much is known about the effects of marijuana on a pregnancy?
It is hard to study marijuana use during pregnancy. Marijuana contains about 400 different chemicals. Some marijuana preparations can be contaminated with other drugs, pesticides, and/or fungi.
Most of the older studies focus on people who inhale marijuana, not ingest it or use it topically. Eating or drinking products with marijuana in them might lead to higher levels of marijuana in the body.
The THC in marijuana has become more potent (stronger) over the years. Results from studies done years ago on marijuana with lower THC levels may report different risks than the risks from stronger THC.
It can be hard to collect correct information on how much and how often marijuana is used. As with any exposure, some people who use marijuana during pregnancy may also use other substances such as alcohol, tobacco, or other drugs, may have medical conditions, and/or have a lack of prenatal care which could increase the chance of pregnancy-related problems.
I use marijuana. Can it make it harder for me to get pregnant?
It is not known if marijuana can make it harder to get pregnant. Some studies suggest that long-term use of marijuana might affect the menstrual cycle, which could make it harder to get pregnant.
I am using marijuana, but I would like to stop before getting pregnant. How long could it stay in my body?
People eliminate drugs at different rates. The way marijuana is used (inhalation, ingesting, topically), how often it is used, and how much is used can affect how long its metabolites can stay in the body. For some people, it might take up to 30 days for the THC metabolite to be gone from the body.
Does using marijuana increase the chance for miscarriage?
Miscarriage is common and can occur in any pregnancy for many different reasons. Based on the studies reviewed, it is not known if using marijuana increases the chance for miscarriage. One study found that people who used marijuana were at an increased risk of having a miscarriage. Other studies have not confirmed this finding.
Does using marijuana increase the chance of birth defects?
Every pregnancy starts out with a 3-5% chance of having a birth defect. This is called the background risk. Most studies have not found an increase in the chance for birth defects in pregnancies exposed to “occasional” marijuana use. Some studies have suggested an increase chance for some birth defects, including gastroschisis (a rare birth defect in which the infants’ intestines stick out of an opening in the abdominal wall).
Does using marijuana in pregnancy increase the chance of other pregnancy-related problems?
Based on the studies reviewed, marijuana might increase risks to a pregnancy. Smoking marijuana can increase carbon monoxide levels in the blood. This can lower the amount of oxygen that passes to the developing pregnancy. Some studies have suggested that among people who smoke marijuana regularly, there is an increased chance for pregnancy complications such as preterm delivery (birth before week 37), low birth weight (weighing less than 5 pounds, 8 ounces [2500 grams] at birth), small length, small head size, and stillbirth. It is not known if these complications are caused by the marijuana use itself, or if the people in these studies had other risk factors (such as smoking cigarettes).
If I use marijuana throughout my entire pregnancy, will it cause withdrawal symptoms in my baby after birth?
There are reports of some newborns who were exposed to marijuana during pregnancy with temporary symptoms, such as jitteriness and irritability. There are also reports of babies who did not have these symptoms. It is important that your healthcare providers know you are taking marijuana so that if symptoms occur your baby can get the care that is best for them.
Does using marijuana in pregnancy affect future behavior or learning for the child?
Based on the studies reviewed, it is not known if marijuana increases the chance for behavior or learning issues. Several studies have followed children exposed to marijuana during pregnancy. Some available information suggests these children are at higher risk for problems with the ability to plan, focus, remember, and multi-task (impaired executive functioning). There might also be a higher chance for exposed children to be impulsive, hyperactive, aggressive, and/or to experience depression and anxiety. These children were also more likely to have problems with paying attention, remembering things, and doing well in school. One study found an increased risk for autism spectrum disorder when marijuana was used during the pregnancy. These issues have been reported more often in children of “heavy” marijuana users (users who smoked one or more marijuana cigarettes per day). The evidence is not conclusive and not all studies agree.
Breastfeeding while using marijuana:
THC passes into breastmilk. The amount of time THC remains in the milk can range from 6 days to 6 weeks. Available information on use marijuana in breastfeeding has not proven clear health concerns when a person who is breastfeeding reports smoking marijuana on a daily basis. There may be a possible delay in motor development (learning to crawl and walk on time).
In some people, use of marijuana might affect prolactin (a hormone that helps the body make milk). There is a concern that frequent marijuana users may see a negative effect on the quality and amount of milk they produce.
Most professional organizations such as the American Academy of Pediatrics, the Academy of Breastfeeding Medicine, and the American College of Obstetricians and Gynecologists advise that people who are breastfeeding avoid using marijuana. Be sure to talk to your healthcare provider about all your breastfeeding questions.
If a male uses marijuana, could it affect fertility (ability to get partner pregnant) or increase the chance of birth defects?
Based on the studies reviewed, marijuana may affect male fertility. Marijuana use might impact sperm, including the number of sperm (sperm count), the size and shape of sperm (morphology) and the ability for sperm to reach the egg (motility). These factors could make it harder to conceive a pregnancy. In general, exposures that fathers or sperm donors have are unlikely to increase the risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/.
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OTIS/MotherToBaby encourages inclusive and person-centered language. While our name still contains a reference to mothers, we are updating our resources with more inclusive terms. Use of the term mother or maternal refers to a person who is pregnant. Use of the term father or paternal refers to a person who contributes sperm.