As cannabis and CBD products become more and more mainstream for recreational use and medical purposes, like treating morning sickness, new concerns about their effects on pregnant and nursing women rise. Now that more states (26 so far, plus the District of Columbia) have decriminalized the use of marijuana and products derived from its compounds, research about safety has finally begun to emerge — and it looks like the cautious view that pregnant and nursing women should abstain was well founded.
A study done at the University of North Carolina School of Medicine found that CBD and THC, also called cannabinoids (CBs), used during early pregnancy can cause damage to an unborn child. Researchers found that exposure to CBs early in pregnancy can affect brain development and cause facial malformations. The effects found are similar to those caused by fetal alcohol syndrome.
Researchers noted these malformations even with a single exposure to CBs in early pregnancy. Both natural and synthetic CBs produced the same results.
These findings could have a wide impact. According to the study, “about 4% of pregnancies are marijuana-exposed, through either recreational use or as an anti-nausea self-medication.” That number could be much higher in some areas. In places like California where CB use is more widespread, nearly 20 percent of pregnancies could be exposed.
Negative effects are amplified by alcohol.
Researchers used mice to test the effects of CBs because they are very similar in development to humans at this phase of pregnancy. The study’s senior author, Scott Parnell, PhD is an assistant professor of cell biology and physiology in the UNC School of Medicine. Parnell is also a member of the UNC Bowles Center for Alcohol Studies. He and his colleagues found that “when CBs and alcohol were used together, the likelihood of these birth defects more than doubled.”
Researchers in the study gave various amounts of CBs and CBs with alcohol on the eighth day of pregnancy, because it is similar developmentally to the third or fourth week of a human pregnancy. This time frame is especially concerning because it is often before women know they are pregnant, or when morning sickness begins — and also when alcohol and CB exposure can be most damaging. The amount of CBD given was an amount considered to be therapeutic in most CBD products on the market. The mount of THC given was the amount generally reached through smoking marijuana.
The study’s first author, Eric Fish, PhD, a research associate in the UNC School of Medicine Bowles Center for Alcohol Studies offers, “Previous studies have shown that CBs and alcohol are frequently used together, and for pregnant women we’re learning that could be very dangerous to a developing child.”
Other experts agree.
The study’s conclusions support initial guidelines from the American Academy of Pediatrics (AAP), published in 2018. The AAP states that additional research is needed, but initial evidence raises “concerns regarding both short-term growth and long-term neurodevelopmental and behavioral consequences of prenatal exposure to marijuana.” Until more information is available, the AAP recommends that physicians educate pregnant and nursing mothers about the potential risks.
The U.S. Food and Drug Administration (FDA) released a statement last month strongly advising against CBD and THC during pregnancy or while breastfeeding. While they also concede that there’s “no comprehensive research studying the effects of CBD on the developing fetus, pregnant mother, or breastfed baby,” they state there is enough evidence to conclude that “there is significant cause for concern.”
Authors of the UNC study plan to continue their research on more human-like models, but until that time it’s better to be safe than sorry. If you’re experiencing the aches, pains and morning sickness that often come along with pregnancy, talk to your doctor about safe remedies.