Background and aims: In the United States, the prevalence of cannabis use during pregnancy has increased whereas tobacco smoking has decreased. This study aimed to estimate the prevalence of tobacco cigarette smoking and cannabis use among new mothers, stratified by breastfeeding status. Additionally, trend analysis was used to examine changes in tobacco and cannabis use over time.
Design: Cross-sectional study based on the National Health and Nutrition Examination Survey (NHANES, 2001-18).
Setting: United States.
Participants: Population-based sample of new mothers (within 2 years of childbirth) aged 20-44 years (n = 1332).
Measurements: For each NHANES data cycle, the prevalence of tobacco smoking measured by self-report or serum cotinine was estimated. Additionally, we estimated the prevalence of cannabis use measured by self-report. Using Joinpoint Regression, we tested for significant changes in trends and produced the average 'data-cycle' percentage change (APC).
Findings: From 2001 to 2018, more than one in five new mothers were tobacco cigarette smokers. New mothers who were breastfeeding were less likely to smoke cigarettes [7.4%, 95% confidence interval (CI) = 4.9%, 10.9% compared with mothers who were not breastfeeding (25.7%, 95% CI = 22.3%, 29.3%]. Results from Joinpoint regression indicated no robust temporal trends for self-reported tobacco smoking (APC = -1.3, 95% CI = -8.6, 6.7; P = 0.7) or for cotinine levels ≥ 4.47 ng/ml (APC = 0.3, 95% CI = -5.0, 5.9; P = 0.9), whereas cannabis use had increased among new mothers (APC = 23.7, 95% CI = 4.8, 46.0; P = 0.02).
Conclusions: Consistent with the increase seen among other subgroups, cannabis use has approximately doubled among US new mothers since 2005. There is no significant evidence of a change in tobacco smoking among US new mothers since 2001.
Keywords: Cannabis; NHANES; new mothers; prevalence; tobacco; trend; women.
© 2020 Society for the Study of Addiction.