PORTLAND, Ore. — THC is the primary psychoactive compound found in cannabis, which has been growing in popularity and availability across the United States. As a result, more pregnant individuals are increasingly turning to cannabis to alleviate common first-trimester symptoms like morning sickness. However, the potential effects of prenatal cannabis use on fetal development have remained inconclusive due to a lack of safety data. Now, a new study is warning mothers-to-be that exposure to THC during pregnancy could have a long-term effect on their child’s development.
Researchers at Oregon Health & Science University (OHSU) have uncovered evidence suggesting that consuming THC (delta-9-tetrahydrocannabinol) during pregnancy could have significant implications for fetal development, leading to lifelong health impacts for the offspring. The preclinical study highlights the need for caution when it comes to cannabis use during pregnancy.
Using a non-human primate model, the researchers at OHSU observed that exposing pregnant subjects to THC resulted in alterations in the placental and fetal epigenome. Epigenetics refers to the chemical modifications to DNA that regulate and control gene expression, determining when and where genes are activated. The observed changes in gene regulation and expression were consistent with those associated with various neurobehavioral conditions, including autism spectrum disorder and attention deficit hyperactivity disorder. These conditions have been linked to adverse health outcomes in childhood and adolescence, such as poor memory, verbal reasoning skills, increased hyperactivity, impulsivity, and inattention.
“Cannabis is one of the most commonly used drugs and is widely available across the country, so there is a common perception that it’s completely safe to use. The reality is that cannabis still carries many health risks for certain populations, including those who are pregnant. If we’re able to better understand the impacts, we can more effectively communicate the risks to patients and support safer habits during the vulnerable prenatal period,” says Lyndsey Shorey-Kendrick, Ph.D., the lead author of the study, in a university release.
In the non-human primate model, THC was administered through daily edibles, and its effects were compared to a placebo group. The researchers focused on evaluating the epigenetic changes in key areas crucial for healthy prenatal development: the placenta, fetal lung, brain, and heart.
The analyses revealed that THC exposure led to alterations in the epigenome, the process that translates genetic information into observable traits. Genes, which are segments of DNA, play vital roles in different bodily and cognitive functions. Any impact on epigenetic processes due to drug exposure is concerning, especially during the critical developmental window of pregnancy.
The research team, including renowned experts such as Eliot Spindel, M.D., Ph.D., Elinor Sullivan, Ph.D., Owen McCarty, Ph.D., and Jason Hedges, M.D., Ph.D., aims to contribute to the limited existing literature on THC use during pregnancy. The findings hold implications for patient counseling and the development of public health policies regarding cannabis use.
Dr. Jamie Lo, the corresponding author of the study, expressed hope that this work would spark a broader dialogue surrounding the risks of cannabis use during the preconception and prenatal periods. Dr. Lo, an associate professor of obstetrics and gynecology, emphasized the importance of improving children’s long-term health through informed decision-making and open discussions about the potential dangers of cannabis use during pregnancy.
This study highlights the significance of considering the potential health impacts of THC use during pregnancy and underscores the need for further research to guide medical practitioners, inform patient counseling, and shape public health policies surrounding cannabis.
The study is published in the journal Clinical Epigenetics.