Study Raises Doubts About the Safety of CBD During Pregnancy

New research found that mice exposed to cannabidiol, or CBD, during pregnancy exhibited concerning behavioral and brain changes.

Cannabidiol (CBD) is a compound found in the cannabis plant that does not produce a "high" like tetrahydrocannabinol (THC). It interacts with the body's endocannabinoid system, which plays a role in regulating sleep, mood, pain, and other functions. Since it doesn't have psychoactive effects, many believe it's relatively safe.

Estimates indicate that around 20% of pregnant individuals use CBD to manage anxiety, nausea, and pregnancy-related pain. While cannabidiol shows promise in reducing these symptoms, the safety of using the compound during pregnancy is unclear.

However, research presented on June 24 at the Federation of European Neuroscience Societies (FENS) Forum 2024 suggests that women may want to reconsider taking CBD during pregnancy due to its potential impacts on the unborn child.

Mouse studies reveal concerns

In 2022, researchers from INSERM Université Aix-Marseille in France used artificial intelligence (AI) to show how prenatal exposure to a low dose of CBD can change early communication and cognitive abilities in mice during the early stages of development.

To conduct the study presented at the FENS Forum 2024, the team injected pregnant mice with a low dose of CBD throughout the gestational period. Another group of rodents served as a control group and were not injected with the compound.

Then, after the mice gave birth, the scientists monitored the offspring and tested them for a wide range of behaviors.

"We found a number of behavioral changes among the mice exposed to CBD," said Ph.D. student and study co-author Ms Alba Caceres Rodriguez in a news release. "CBD-exposed females tended to move around their new environment more compared to females that didn't receive CBD during gestation. Furthermore, compared to control mice, both male and female mice treated with CBD established more physical contact with each other."

Moreover, when the team examined the brains of adult offspring, they found that CBD exposure during pregnancy significantly changed how neurons in the IC function. Specifically, they lost their cellular identity and stopped behaving like typical neurons, which could impact sensory system functioning and reduce the ability to understand and react to the environment.

In addition, the research team says that several studies have shown that IC dysfunction increases the risk of developing mental health conditions, including anxiety, addiction, depression, and schizophrenia.

Is CBD safe during pregnancy?

In a mouse study published in 2021, researchers found that CBD exposure during pregnancy may affect mood and cognition in offspring long after the exposure has ended. Moreover, female mice exposed to CBD in utero exhibited higher anxiety levels but improved memory behavior.

In addition, a 2023 mouse study found that CBD exposure during the gestational period disrupts neurodevelopment and behavior after birth, altering pain sensitivity in male mice and reducing problem-solving skills in females.

Still, the scientists involved in these studies and the latest research presented at the FENS Forum conducted their investigations in rodents, so it's unclear whether CBD use among pregnant humans could result in the same effects. Despite these unknowns, the research team remains concerned.

"Scientific evidence has proven that CBD crosses the placenta, can reach the brain of rodents and human embryos, and is also present in breast milk," Caceres Rodriguez said. "Therefore, it's a public health priority to understand the impact of CBD on the developing nervous system as we don't yet know the consequences of CBD exposure to the brain during development."