Use of E-Cigarettes and Cigarettes During Late Pregnancy Among Adolescents.

Importance: Pregnant adolescents sometimes use cigarettes; however, little is known about e-cigarette use among pregnant adolescents, a population with increased health vulnerability. Objective: To examine yearly trends, sociodemographic and pregnancy-related determinants, and the association with small-for-gestational-age (SGA) birth of e-cigarette and/or cigarette use during late pregnancy among adolescents. Design, Setting, and Participants: This cohort study used existing data from the 2016-2021 Pregnancy Risk Assessment Monitoring System on 10 428 US adolescents aged 10 to 19 years who had a singleton birth with complete data on e-cigarette or cigarette use and SGA birth. Exposure: Adolescents reported e-cigarette and cigarette use during the last 3 months of pregnancy. Main Outcomes and Measures: SGA birth (birth weight below the 10th percentile for the same sex and gestational duration) was determined from birth certificates. Multivariable logistic regression was used to compare the odds of SGA birth across pregnant adolescents who exclusively used e-cigarettes, exclusively used cigarettes, used e-cigarettes and cigarettes, or did not use either. Results: Of the 10 428 pregnant adolescents, 72.7% were aged 18 or 19 years; 58.9% self-identified as White and 23.3% as Black; and 69.8% were non-Hispanic. The weighted prevalence of exclusive e-cigarette use during late pregnancy increased from 0.8% in 2016 to 4.1% in 2021, while the prevalence of exclusive cigarette use decreased from 9.2% in 2017 to 3.2% in 2021. The prevalence of dual use fluctuated, ranging from 0.6% to 1.6%. White pregnant adolescents were more likely than those who self-identified as another race and ethnicity to use e-cigarettes (2.7% vs 1.0% for American Indian or Alaska Native adolescents, 0.8% for Asian or other race adolescents, 0.6% for Black adolescents, and 0.7% for multiracial adolescents). Compared with those who did not use either product, adolescents who exclusively used e-cigarettes (16.8% vs 12.9%; confounder-adjusted odds ratio [AOR], 1.68 [95% CI, 0.89-3.18]) or who used cigarettes and e-cigarettes (17.6% vs 12.9%; AOR, 1.68 [95% CI, 0.79-3.53]) had no statistically significant difference in risk of SGA birth. However, adolescents who exclusively used cigarettes had a more than 2-fold higher risk of SGA birth (24.6% vs 12.9%; AOR, 2.51 [95% CI, 1.79-3.52]). Conclusions and Relevance: This cohort study suggests that pregnant adolescents increasingly used e-cigarettes, with the highest use among White adolescents. Results from this analysis found that, unlike cigarette use, e-cigarette use during late pregnancy was not statistically significantly associated with an increased risk of SGA birth among adolescents. Due to the uncertainty of this nonsignificant association, future research could benefit from a larger sample size.