Marijuana and pregnancy


  • No amount of marijuana has been proven safe to use during pregnancy.

  • Using marijuana during pregnancy may cause problems for your baby, like premature birth, problems with brain development and stillbirth.

  • It’s not safe to use marijuana to treat morning sickness. Talk to your health care provider about treatments that are safer for your baby.

  • If you use marijuana, don’t breastfeed. You may pass chemicals from marijuana to your baby through breast milk.

  • Talk to your provider if you need help to quit using marijuana or any other street drug.

What is marijuana?

Marijuana (also called pot, weed and cannabis) is a drug that comes from the dried leaves, flowers, stems and seeds of the cannabis plant. Marijuana is the most commonly used street drug during pregnancy. Marijuana is illegal in many states. But in some states, it’s legal to use and treat some illnesses (called medical or medicinal marijuana).

Marijuana has a chemical in it called delta-9-tetrahydrocannabinol (also called THC). This chemical can affect how your brain works and make it hard to think clearly. THC and other chemicals in marijuana may change your sense of sight, sound and touch. 

Using marijuana during pregnancy may cause problems for your baby before and after birth.

What is medical marijuana?

Medical marijuana (also called medicinal marijuana) is marijuana used to treat a health condition, like cancer, HIV, multiple sclerosis, or severe pain or nausea. In many states, medical marijuana is legal to use with a recommendation from your health care provider. The Food and Drug Administration (also called FDA) has not approved marijuana as a safe and effective medicine for any health condition. The FDA is a government agency that helps protect the health of Americans by making sure that products like food, medicine and cosmetics, are safe.

In some states, marijuana is legal for personal use that’s not for medical reasons.

Even if it’s legal where you live for either personal or medical use, it’s not safe to use marijuana during pregnancy, even to treat morning sickness. Morning sickness is nausea and vomiting that often happens in the first few months of pregnancy. No amount of marijuana has been proven safe during pregnancy, even to treat nausea. If you’re thinking of using marijuana to help with morning sickness, talk to your provider about other treatments that may be less harmful to your baby. 

Can using marijuana cause problems before pregnancy?

Yes. Before pregnancy, using marijuana can affect your fertility and make it hard for you to get pregnant. Marijuana can affect: 


  • Hormones that your body needs to get pregnant. Hormones are chemicals made by the body.
  • Your menstrual cycle. This is the process of your ovaries releasing an egg every month.
  • A man’s sperm count (the number of sperm he makes). A man’s sperm fertilizes a woman’s egg to begin a pregnancy. 


Can using marijuana during pregnancy cause problems for your baby?

Yes. When you use marijuana during pregnancy, THC and other chemicals may pass through the placenta to your baby. The placenta grows in your uterus (womb) and supplies your baby with food and oxygen through the umbilical cord. Chemicals from marijuana also may pass to your baby's brain.

We need more research to find out how marijuana may affect you and your baby during pregnancy. Women who use marijuana may smoke cigarettes, drink alcohol or use other street drugs, making it hard to know exactly how marijuana affects pregnancy. Some studies suggest that if you use marijuana during pregnancy, your baby may have problems, including:


  • Premature birth. This is birth that happens too early, before 37 weeks of pregnancy. 
  • Fetal growth restriction (also called growth-restricted, small for gestational age and small for date) and low birthweight. Fetal growth restriction is when a baby doesn’t gain the weight she should before birth. Low birthweight is when a baby is born weighing less than 5 pounds, 8 ounces. Your baby also may have short body length or small head size.
  • Anencephaly. This is one of the most severe neural tube defects (also called NTDs). NTDs are birth defects in the neural tube, the part of a developing baby that becomes the brain and spine. Babies with this condition are missing major parts of the brain, skull and scalp. They do not survive long after birth, usually for just a few hours. Babies exposed to marijuana during the first month of pregnancy are at increased risk of having anencephaly.
  • Anemia. This is when your baby doesn’t have enough healthy red blood cells to carry oxygen to the rest of his body.
  • Problems with brain development
  • Stillbirth. This is when a baby dies in the womb after 20 weeks of pregnancy.   


If you use marijuana during pregnancy, your baby may have problems after birth, too. He may be more likely than other babies to spend time in a neonatal intensive care unit (also called NICU). A NICU is the nursery in a hospital where sick newborns get care. Exposure to marijuana during pregnancy may cause these problems for your baby after birth: 


  • Withdrawal symptoms, like tremors (shakes) or long periods of crying after birth. These symptoms usually go away within a few days after birth.
  • Problems with sleeping
  • Problems with behavior, memory, learning, problem-solving, depression and paying attention


How does using marijuana affect breastfeeding?

You may pass THC and other chemicals from marijuana to your baby through breast milk. If you breastfeed your baby and smoke marijuana, your baby may be at increased risk for problems with brain development. Marijuana also may affect the amount and quality of breast milk you make. The American Academy of Pediatrics recommends that breastfeeding moms stay away from marijuana to help keep breast milk safe and healthy.

How is marijuana used?

Marijuana often is smoked in hand-rolled cigarettes (also called joints), cigars (also called blunts) or in pipes. It’s sometimes used with a vaporizer that allows users to inhale it (breathe in) without the smoke. Some people mix marijuana with food, like brownies, cookies or candy. Some use a method called dabbing or dabs. Dabbing is when users smoke sticky products called extracts or resins that are made from the hemp plant. These extracts contain high amounts of THC. When you smoke them, you get a stronger high than from smoking hemp leaves. 

There are forms of marijuana extracts: 

  1. Hash oil or honey oil. These are both gooey liquids.
  2. Wax or budder, a soft solid like lip balm
  3. Shatter, a hard, yellow-brown solid. It’s called shatter because it looks like glass and shatters when you scrape it. 

Making marijuana extracts is dangerous because you have to use butane (lighter fluid). Using butane can cause fires, explosions and severe burns.

Can using marijuana harm your general health?

Yes. The more marijuana you use, the more likely you are to have problems, including:

  • Very fast heart rate
  • Lung problems, including  bronchitis and chronic cough (like a smoker’s cough)
  • Trouble paying attention or thinking clearly
  • Memory problems
  • Trouble sleeping
  • Clumsiness and poor coordination and balance

How can you get help to quit using marijuana?

Talk to your health care provider. He can help you get treatment to quit. Use the Substance Abuse Treatment Facility Locator or call (800) 662-4357.

More information

National Institute on Drug Abuse (NIDA)

Mother to Baby

Last reviewed: January, 2017