A recent meta-analytic study has explored the connection between maternal cannabis use during pregnancy and the occurrence of autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) symptoms in their children. The researchers found that children whose mothers used cannabis during pregnancy were more likely to have symptoms of ADHD compared to children whose mothers were not using cannabis during pregnancy. The findings were published in the Journal of Psychiatric Research.
Cannabis sativa is a plant that contains psychoactive compounds, primarily tetrahydrocannabinol (THC) and cannabidiol (CBD). It can be consumed in various forms, including smoking dried leaves and flowers, ingesting it in edibles like cookies or candies, using oils or tinctures, or vaporizing. Recreationally, cannabis is used for its relaxing and euphoric effects, while medicinally, it is used to alleviate symptoms such as chronic pain, anxiety, and nausea. The legal status of cannabis varies widely across different regions, with some areas allowing its use for medical and/or recreational purposes, while others prohibit it entirely.
Recent research findings indicate that the use of cannabis among pregnant women has been increasing substantially. This has raised concerns among scientists as studies on animals indicate that prenatal exposure to cannabis is associated with various cognitive deficits in newborns. Human studies have similarly found that children born to mothers who used cannabis during pregnancy are at an increased risk of developing ADHD and ASD, although these findings have been inconsistent.
Study author Abay Woday and his colleagues wanted to systematize the results of these studies and see whether there is indeed an association between the use of cannabis by mothers during pregnancy and ADHD and ASD symptoms of their children during childhood and adolescence.
ADHD is a neurodevelopmental disorder characterized by persistent patterns of inattention, hyperactivity, and impulsivity that interfere with everyday social functioning, particularly in the school environment. It is usually first detected in childhood, but the symptoms can persist in adolescence and adulthood as well.
ASD is a complex developmental condition that adversely affects communication abilities, behavior, and social interaction in varying degrees. Individuals with ASD tend to have difficulties with social communication, exhibit repetitive behaviors, and show a narrow range of interests.
For their new study, the authors scoured scientific databases for studies that examined the relationship between prenatal cannabis use and offspring neurodevelopmental disorders, specifically focusing on ADHD and ASD. Out of 8,444 articles initially found, only 14 contained the relevant data needed for their analysis—10 linked to ADHD and 4 to autism in children. The studies included 203,783 participants overall.
Results that children exposed to cannabis in utero had a statistically significant increased risk of developing symptoms of ADHD and/or being diagnosed with the disorder. Prenatal cannabis exposure was also associated with an increased likelihood of ASD symptoms in children. However, this finding was not statistically significant, implying that the observed association between cannabis in utero and ASD symptoms could be due to chance.
The results remained significant even after accounting for factors such as tobacco and alcohol use during pregnancy and maternal mental health issues.
“In this systematic review and meta-analysis, we found that offspring exposed to prenatal cannabis use had an increased risk of ADHD symptoms and ASD compared with unexposed offspring. Adjustment for maternal mental health problems, maternal alcohol use, and tobacco smoking did not substantially alter the observed associations. The findings suggest the importance of implementing prevention and early interventions among offspring exposed to prenatal cannabis use,” the study authors concluded.
The paper, “Prenatal cannabis use and the risk of attention deficit hyperactivity disorder and autism spectrum disorder in offspring: A systematic review and meta-analysis,” was authored by Abay Woday Tadesse, Berihun Assefa Dachew, Getinet Ayano, Kim Betts, and Rosa Alati.