Prenatal cannabis exposure may increase risk for psychopathology during middle childhood, according to results of a cross-sectional study published in JAMA Psychiatry.
"Although the number of studies on the potential effects of prenatal cannabis exposure is increasing, there have still been relatively few investigations," Sarah E. Paul, BA, of the department of psychological and brain sciences at Washington University in St. Louis, told Healio Psychiatry. "Further, there has been little consistency in the findings. Heterogeneity in study design, covariates, sample size and measurement of cannabis use in pregnancy and of outcome variables have made it difficult to draw strong conclusions from the findings."
"Additionally, many previous studies have not been able to account for timing of prenatal cannabis exposure, which conceivably leads to some heterogeneity in findings based on timing of the endocannabinoid system development," Paul added.
To identify potential adverse outcomes among offspring related to prenatal cannabis exposure, Paul and colleagues analyzed data of 11,489 children with prenatal cannabis exposure who were included in the baseline session of the Adolescent Brain and Cognitive Development (ABCD) Study. The ongoing longitudinal ABCD Study included children aged 9 to 11 years, as well as a parent or caregiver, from across the United States.
Paul and colleagues used prenatal exposure to cannabis before and after maternal knowledge of pregnancy as the exposure. Main outcomes and measures were symptoms of psychopathology among children which included psychotic-like experiences, internalizing, externalizing, attention, thought and social problems, as well as cognition, sleep, birth weight, gestational age at birth, body mass index and brain structure. Familial, pregnancy and child variables served as covariates.
Results showed 5.7% of children who were included had prenatal cannabis exposure. Compared with no exposure, cannabis exposure only before (N = 413) and after (N = 242) maternal knowledge of pregnancy were linked to greater psychopathology characteristics among offspring. These included psychotic-like experiences, internalizing, externalizing, attention, thought, social problems, sleep problems and body mass index. The investigators also noted lower cognition and gray matter volume. Further, only exposure after knowledge of pregnancy was linked to lower birth weight, as well as total intracranial and white matter volumes compared with no exposure and exposure only before knowledge of pregnancy. Exposure after maternal knowledge of pregnancy remained associated with greater psychotic-like experiences and externalizing, attention, thought and social problems when potentially confounding covariates were included. However, exposure only before maternal knowledge of pregnancy was not different from no exposure on any outcomes when potentially confounding variables were included.
"Currently, cannabis use among pregnant women should be discouraged," Ryan Bogdan, PhD, associate professor in the department of psychological and brain sciences at Washington University in St. Louis, told Healio Psychiatry. "It is also important that expecting mothers who may be experiencing difficulties are not stigmatized. Stopping substance use is difficult, especially during challenging times such as pregnancy."
"Physician and psychologist support and empirically-based paradigms aimed at helping pregnant women quit are important," Bogdan added. "Finally, couples who are planning on having a child may wish to consider addressing cannabis use before they begin attempting to conceive and pregnancy-related stressors mount."
This article is originally published in healio.