Cannabis use after pregnancy shows no link to high blood pressure

To evaluate whether cannabis exposure after a first pregnancy was associated with incident hypertension 2-7 years after that pregnancy. This was a secondary, cross-sectional analysis of the nuMoM2b (Nulliparous Pregnancy Outcomes Study: Monitoring Mothers to Be) Heart Health Study. Nulliparous participants were followed up from the first trimester to an in-person study visit 2-7 years after their pregnancy. The primary exposure was cannabis use after pregnancy, which was detected by having urine positive for THC-COOH (11-nor-9-carboxy-delta-9-tetrahydrocannabinol) metabolite (cutoff 15 ng/mL or higher) at the study visit at 2-7 years. The primary outcome of this analysis was incident hypertension (systolic blood pressure 140 mm Hg or higher or diastolic blood pressure 90 mm Hg or higher) or use of an antihypertensive agent at the time of the follow-up visit at 2-7 years. A multivariable logistic regression model was fitted and adjusted for covariates that were selected a priori, including nicotine exposure assessed at the follow-up visit (measured through serum cotinine levels or self-report), to assess whether cannabis exposure was associated with the occurrence of incident hypertension. Of 4,079 participants, 216 (5.3%) developed hypertension by the study visit at 2-7 years. Neither exposure to cannabis in 406 participants (10.0%) (adjusted odds ratio [AOR] 1.05, 95% CI, 0.63-1.76) nor active nicotine exposure (AOR 1.03, 95% CI, 0.66-1.63) was associated with incident hypertension in multivariable modeling. In this population of nulliparous women, cannabis exposure 2-7 years after pregnancy was not associated with incident hypertension after controlling for nicotine exposure and known risk factors measured during the pregnancy.