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Marijuana or CBD During Pregnancy: Is It Safe?

Though not everyone talks about it openly, marijuana and related products like CBD (cannabidiol, one of the active ingredients in marijuana) are a big topic in the world of motherhood. While there is limited research available on what effect marijuana has on a baby in utero, researchers and physicians warn against its use by moms-to-be. Here are some reasons why, and some tips to help you navigate this topic.

Why Do Mothers Use Marijuana?

Marijuana is illegal and classified as a Schedule I substance under federal law, the same category as heroin and LSD. But that thinking appears outdated to many, since several states have legalized marijuana for recreational use and even more allow medical marijuana.

If you peruse any motherhood app, website or forum, there are likely to be questions and anecdotes about using marijuana before, during or after pregnancy. Some common uses of cannabis are to ease morning sickness during the first trimester and to combat the anxiety that can sometimes accompany a newborn. CBD oils and products are also used in an attempt to relieve aches and pains caused by pregnancy and delivery.

Some mothers perceive marijuana as a natural alternative to prescription medications.

No matter the reasoning behind the use of marijuana or CBD during or after pregnancy, there are some key findings to understand before doing so. And if you’re struggling with substance abuse, seek help.

What the Research Shows About Marijuana Use During Pregnancy

UNC School of Medicine researchers are producing some of the first solid studies on what marijuana use during pregnancy can do to a developing baby.

They’ve learned that cannabinoids (the active ingredients in cannabis, including CBD and THC) can cause brain and facial birth defects if used during the first trimester of pregnancy. Scott Parnell, PhD, assistant professor of cell biology and physiology, along with his research lab in the UNC Bowles Center for Alcohol Studies, has shown this in mice, which are very accurate models of early human pregnancy.

Dr. Parnell and fellow researchers found these defects happened after a one-time exposure of cannabinoids. They also discovered that because of the way cannabinoids interact with our bodies on a basic cellular level, when combined with alcohol, a CBD or THC exposure more than doubled the likelihood of these developmental changes.

The timing of this study is notable. The exposures happened during what would be equivalent to the third and fourth weeks of pregnancy in humans, which is before most women know they are pregnant.

“It is concerning how little we know about the use of marijuana, its cannabinoids and products like CBD oil during pregnancy,” Dr. Parnell says. “We know that there is no safe period to drink alcohol during a pregnancy, and I think this research shows the same is likely true of marijuana use.”

While this is the first study to show that marijuana directly caused abnormal development, other studies have shown associations between marijuana use during pregnancy and preterm birth and low birth weight, along with difficulties in cognitive abilities and behavioral control during the early childhood years. Some of these studies are several years old; the classification of marijuana as a Schedule I drug makes research difficult.

A Pediatrician’s Point of View

Based on the research that does exist on marijuana use in pregnancy, the U.S. Food and Drug Administration advises against the use of marijuana or any of its products, including CBD, during pregnancy or while breastfeeding, as does the American College of Obstetricians and Gynecologists.

While physicians rely on these recommendations and cite research when offering their advice to new mothers, they also use the wisdom they’ve gained from years of experience.

“Doctors like to give reasons for the instructions we give patients, but we can’t do that as well in this case,” says pediatrician Alison Sweeney, MD. “We extrapolate on things we do know, which is the fact that what goes into your body shows up in your breast milk and then is passed on to your baby.”

The medical community is still learning how long marijuana stays in breast milk, Dr. Sweeney adds, but studies have shown THC can be found in breast milk up to six days after a mother uses the drug. Because there’s no great way to tell just how long marijuana will stay in breast milk, the safest option is not to use it while breastfeeding, she says.

The bottom line is that there is no research showing that it is safe to use marijuana or its products during pregnancy or while breastfeeding, Dr. Sweeney says.

As for CBD oils or products applied to the skin, she says, “we’ve established through research that when people put sunscreen on their skin, it gets absorbed into the body and can show up in blood and urine. So you could make the connection that if CBD oil or lotion is used on the skin, it could also get transferred to a developing baby and show up in breast milk.”

Her biggest suggestion to new mothers is to talk to a physician if they are thinking about using marijuana or any other substance that they are unsure of.

“We want women to seek care and help. We want them to ask questions,” Dr. Sweeney says. “A doctor’s job is not to penalize you for asking questions. It is to provide information that can help you make the best decisions for you and your baby.”

How to Manage Without Marijuana

For women experiencing nausea during pregnancy, several medications have proved safe and effective, Dr. Sweeney says.

“Some of the medicines cause increased sleepiness, so you should talk to your doctor about which is right for you. When combined with other measures, like anti-nausea wristbands, these medications work pretty well.”

If you already take a prescription for anxiety or depression before getting pregnant, talk to your doctor about whether to continue that medication through pregnancy, because in several cases it is safe to do so.

After pregnancy, the number of medications a breastfeeding mother can take for anxiety or depression expands further, Dr. Sweeney says. Again, the best thing to do is talk to your doctor to formulate a treatment plan. If you think you may have postpartum depression or another type of mood disorder, it’s especially important to seek treatment.

There are other ways to cope with the stress of a new baby. You can find a support group of moms in your community, and make sure your friends and family are ready to lend a hand at home. You could also try yoga or meditation to help relieve some anxiety.

“Being a new mom is a type of happy crisis,” Dr. Sweeney says. “The feelings of anxiety are heightened by being in such a new situation, and sleep deprivation can exacerbate those feelings. Your pediatrician can be a great resource for all types of questions after delivery, so take advantage of that for yourself. And please know you are not alone.”


If you would like to talk to an OB-GYN or a pediatrician, find one here.