Marijuana (Cannabis) and Pregnancy

Cannabis is a type of plant that contains chemicals called tetrahydrocannabinol (THC) and cannabidiol (CBD). THC is what can cause you to feel relaxed and “high” when you use marijuana or other cannabis products.

Cannabis also has CBD and other chemicals that affect different organs in the body, including the brain, lungs, blood vessels, heart, and liver. Researchers are still learning about the effects that THC, CBD, and other chemicals in cannabis have on your fetus.

Medical marijuana is any use of cannabis that is prescribed by a doctor. Medical marijuana is legal in many states, but it is illegal under federal law. The U.S. Food and Drug Administration (FDA) has not approved medical marijuana for the treatment of any medical condition.

There are some FDA-approved medications that contain a form of THC that does not produce a “high.” These medications are different from medical marijuana, and they also require a doctor’s prescription.

Edible cannabis (sometimes called “edibles”) is processed differently in the body than cannabis that is smoked or vaped. Because edibles go through the digestive system, it takes longer to feel the effects. This leads some users to eat more edibles so that they can feel the effects more quickly. And because it is not always possible to tell how strong the cannabis is before eating it, there is a higher risk of overdose with edibles than with smoking or vaping.

Your obstetrician–gynecologist (ob-gyn) should ask you about any use of substances as part of routine prenatal care, including alcohol, tobacco, cannabis, illegal drugs, and prescription medications used for a nonmedical reason. Doctors ask about these substances because they need to know about anything that could harm you or your fetus. And if you are using these substances to help problems like pain, sleeplessness, stress, or nausea, your ob-gyn can help you find alternatives that are safe during pregnancy.

After tobacco and alcohol, cannabis is the most commonly used substance during pregnancy. When you eat, smoke, or vape cannabis products, the chemicals reach the fetus by crossing the placenta. Smoking or vaping also lowers the level of oxygen in your body, which can cause breathing problems for you and development problems for your fetus.

Researchers are still learning about the effects of cannabis during pregnancy and birth. Studies are not always clear, but researchers and doctors have found that:

• The chemicals in cannabis products may disrupt the fetus’s normal brain development, which may lead to learning problems and behavior disorders.

• Using both cannabis and tobacco during pregnancy can increase the risk of preterm birth.

• Babies exposed to cannabis during pregnancy may be born with low birth weight, be smaller at birth, or be more likely to stay in the neonatal intensive care unit (NICU).

• Cannabis use during pregnancy can increase the risk of stillbirth and infant death.

You may have heard that you can use cannabis for morning sickness. While it is true that cancer patients often use cannabis to help with nausea, that type of nausea is different than the type that happens during pregnancy. There is no evidence that cannabis products are helpful in managing morning sickness.

If you have morning sickness, talk with your ob-gyn. There are things you can do to help, including temporarily changing your food or other lifestyle choices. There is also an FDA-approved medication that can safely treat nausea and vomiting of pregnancy.

No. Medical marijuana is no different than recreational (nonmedical) cannabis. It is not safer, and it has all the harmful effects of recreational cannabis.

As with any medication during pregnancy, it is important to let your ob-gyn know if you are using medical marijuana. You can discuss other treatment options that are safe to use during pregnancy.

Yes. It is best to stop using cannabis before trying to get pregnant. The effects of cannabis on the fetus can be seen as early as 5 weeks of pregnancy, which is before most women even know they’re pregnant.

If you used cannabis before you knew you were pregnant, stopping or reducing your use at any point, especially in the first trimester, is a good way to reduce the risks to your fetus.

Yes. Using cannabis may make it harder to get pregnant by affecting your partner’s sperm. Cannabis may

• Lower the amount of sperm (“sperm count”)

• Cause sperm to move less and have trouble reaching an egg

• Change the shape of sperm and make them less effective at fertilization

Some people think that CBD is safer than marijuana because it does not contain THC. But CBD is not regulated by the FDA, and many products have been found to be contaminated with THC and other harmful substances. CBD itself can cause liver problems and harmful interactions with other medications. Both the FDA and ACOG recommend avoiding CBD during pregnancy.

Researchers are still learning about the effects of cannabis exposure during pregnancy. Studies are not always clear, but researchers and doctors have found that babies and children who were exposed to cannabis during pregnancy:

• May have problems with sleep and irritability during their first month of life.

• May have learning and behavioral problems later in life.

Researchers don’t know much about the effects of cannabis on breastfed babies. Because it is not clear how much THC and other chemicals in cannabis can transfer through breast milk, ACOG recommends avoiding cannabis during breastfeeding.

However, the benefits of breastfeeding are likely to be much more important than the potential harms of cannabis exposure through breast milk. So, you shouldn’t stop breastfeeding even if you can’t stop using cannabis.

Keep in mind that secondhand smoke and vape aerosol from cannabis products may be just as harmful as secondhand smoke from tobacco, especially for babies and young children. If you do smoke or vape, make sure you do it when you’re away from your baby. 

If you use edible cannabis or any form of marijuana, keep it safely locked away. If your child finds your edibles, they can easily overdose and become sick.

Yes, cannabis products are addictive, especially because advanced technology and growing methods mean that the amount of THC in cannabis products is higher than ever. About 1 in 3 users develops cannabis use disorder. This disorder can make you feel like you need more cannabis to achieve the same effects, and cause withdrawal symptoms when you try to stop using cannabis products. Symptoms include irritability, trouble sleeping, cravings, and restlessness.

The most severe form of cannabis use disorder is addiction. About 1 in 10 cannabis users becomes addicted. With addiction, you feel like you can’t stop using a substance even when it causes problems with relationships, work, school, or your physical or mental health.

If you are having trouble with substance use, your ob-gyn can offer advice or resources to help you quit. ACOG believes that if you have a substance use problem, you should receive medical care and counseling services to help you quit.

If you want to quit using cannabis products and you need help, you can find resources on the website of the Substance Abuse and Mental Health Services Administration (SAMHSA): www.samhsa.gov. SAMHSA also has a 24-hour treatment referral line: 800-662-HELP (4357).

Digestive System: A system made up of the stomach, bowels, liver, gallbladder, and pancreas. This system breaks down food and removes waste from the body.

Egg: A reproductive cell made in and released from the ovaries. Also called the ovum.

Fertilization: A multistep process that joins the egg and the sperm.

Fetus: The stage of human development beyond 8 completed weeks after fertilization.

Liver: An organ that regulates most of the chemicals in the body and filters the blood to remove toxins.

Low Birth Weight: Weighing less than 5 1/2 pounds (2,500 grams) at birth.

Nausea and Vomiting of Pregnancy: A condition that develops in early pregnancy, usually starting before 9 weeks of pregnancy.

Neonatal Intensive Care Unit (NICU): A special part of a hospital where sick newborns receive medical care.

Obstetrician-Gynecologist (Ob-Gyn): A doctor with medical and surgical training and education in the female reproductive system.

Oxygen: An element that people breathe in to sustain life.

Placenta: An organ that provides nutrients to and takes waste away from the fetus.

Preterm: Less than 37 weeks of pregnancy.

Sperm: A cell made in the testicles that can fertilize an egg.

Stillbirth: Birth of a dead fetus.

Trimester: A time period of 3 months. There are three trimesters in pregnancy: the first trimester, second trimester, and third trimester.