Association between maternal e-cigarette use during pregnancy and low gestational weight gain

To evaluate the risk of low gestational weight gain (GWG) in women who use electronic cigarettes (e-cigarettes), combustible cigarettes, or both e-cigarettes and combustible cigarettes (dual use) during pregnancy.

We conducted a secondary analysis of the data from 176 882 singleton pregnancies in the 2016-2020 US Pregnancy Risk Assessment Monitoring System (PRAMS). Postpartum women self-reported their use of e-cigarettes and/or cigarettes during the last 3 months of pregnancy. Low GWG was defined as the total GWG less than 12.7 kg, less than 11.3 kg, less than 6.8 kg, and less than 5.0 kg (<28, <25, <15, and < 11 lb) for women with underweight, normal weight, overweight, and obesity, respectively. We used multivariable logistic regression to estimate the odds ratios (ORs) of low GWG, adjusting for confounders.

In this national sample, 921 (weighted percentage, 0.5%) of women were e-cigarette users and 1308 (0.7%) were dual users during late pregnancy. Compared with non-users during late pregnancy (40 090, 22.1%), cigarette users (4499, 28.0%) and dual users (427, 26.0%) had a higher risk of low GWG, but e-cigarette users had a similar risk (237, 22.1%). Adjustment for sociodemographic and pregnancy confounders moderately attenuated these associations: confounder-adjusted ORs 1.26 (95% confidence interval [CI] 1.18-1.35) for cigarette users, 1.18 (95% CI 0.96-1.44) for dual users, and 0.99 (95% CI 0.78-1.27) for e-cigarette users.

Unlike combustible cigarette use, e-cigarette use during late pregnancy does not appear to be a risk factor for low GWG.