Prevalence and correlates of cannabis use in pregnancy and while breastfeeding: A survey-based study

Objectives Recreational cannabis use has been legal in Canada since October 2018. This study sought to determine current prevalence and trends of cannabis use among pregnant women in the greater Hamilton area. Methods An anonymous survey was distributed in May–October 2019 to pregnant patients attending family practice, midwifery, low- and high-risk obstetrical clinics. It was carried out via electronic tablet, and included lifetime and in-pregnancy cannabis use, intent for postpartum cannabis use, and characteristics of use. Demographic data included age, relationship status, partner cannabis use, educational attainment, and household income. Descriptive statistics were calculated, and logistic regression analyses were performed to explore relationships between cannabis use and demographics. Results Among 478 respondents, 11.3% had used cannabis at any point in pregnancy, 4.2% were currently using and 4.8% intended to use while breastfeeding. Of current users, 65.0% reported using at least weekly and 95.0% reported nausea, sleep, or anxiety as reasons for use. Women who used cannabis in pregnancy and intended to use while breastfeeding were more likely to report partner cannabis use and lower educational attainment. Women reporting partner cannabis use were 3.3-fold more likely to use cannabis in pregnancy (p<0.001; 95% CI 1.77–6.17) and women without post-secondary education were 8.6-fold more likely to use cannabis than university-educated women (P<0.0001; 95% CI 3.78–19.52). Conclusions Partner cannabis use and lower educational attainment predict likelihood of in-pregnancy cannabis use and intent for postpartum use. Education about safer alternatives for coping with nausea, sleep difficulties and anxiety may help reduce the prevalence of cannabis use in pregnancy.