Marijuana use and sleep quality during pregnancy

Objective: Marijuana use among pregnant women is on the rise in part due to the perception that marijuana may improve problems related to pregnancy such as poor sleep. This study's objective was to examine associations between marijuana use and sleep quality among a sample of women during pregnancy.

Material and methods: The sample included women seeking prenatal care at The Ohio State University Wexner Medical Center (2010-2015). Intake assessments included medical, demographic, and socioeconomic domains, as well as the Pittsburgh Sleep Quality Index. Marijuana use during pregnancy was determined using urine screens, chart abstraction, and self-report. Women completed standardized questionnaires regarding sleep quality, depressive symptoms, anxiety, stress, and discrimination at enrollment and each subsequent trimester. A linear mixed-effect model was used to assess the relationship between sleep variables and marijuana use adjusted for maternal race, education, household income, age, marital status, depressive symptoms, anxiety, stress, discrimination, and use of tobacco and other substances during pregnancy. Women completed the sleep quality assessments for a total of 294 pregnancies, which comprise the study population.

Results: Among the study sample (n = 294), 93 women used marijuana and 201 women did not use marijuana during their pregnancies. Women who used marijuana (n = 93) were more likely to identify as African-American (73% vs 58%; p = .01), report government health insurance (98% vs 89%; p = .001), use tobacco during pregnancy (66% vs 33%; p < .001), report less household income (70% vs 43% < 10,000 annual household income; p < .001), and be unmarried (69% vs 49%; p < .001) compared to women who did not. Mean sleep quality was similar among women who did (µ = 7.6; SD = 4.0) and did not use marijuana during pregnancy (µ = 7.7; SD = 4.0), and both groups had a mean score worse than the conventional cutoff for poor sleep quality (>5). In fact, both groups reported worse sleep than is typically observed among cohorts reporting poor sleep, which have ranged from 5.3 to 6.3.

Conclusions: Current findings did not suggest differences in sleep quality between women who used and did not use marijuana during pregnancy. Findings are contrary to the perception that marijuana use alleviates sleep-related problems during pregnancy. Given well-documented adverse outcomes associated with prenatal marijuana exposure for children and the increase in women using marijuana during pregnancy, providers should be prepared to discuss possible harms associated with marijuana use during pregnancy as well as provide psychoeducational information and service referrals to those interested. Future studies could improve upon this design by assessing objective measures of sleep, such as actigraphy, as well as marijuana use repeatedly throughout pregnancy, which may be a more optimal strategy for illuminating potential relationships between marijuana use and sleep during pregnancy.