Higher Smoking Abstinence Rate Found Among e-Cigarette Users During Late Pregnancy

E-cigarette users had a higher smoking abstinence rate during late pregnancy than those who used nicotine replacement therapy (NRT), like nicotine gum or patches, according to a study published in JAMA Network Open.

Smoking cigarettes during pregnancy has been proven to severely affect the health of the mother and child. The researchers explained that past studies found several benefits of maternal smoking cessation, including increased birth weight, height, and head circumference.

Consequently, pregnant individuals began using e-cigarettes to aid in smoking cessation given their potential for harm reduction, as “gestational exposure to e-cigarettes has been associated with lower rates of small-for-gestational-age birth as well as improved neurobehavioral scoring compared with combustible cigarettes,” the study authors wrote. Despite their popularity, limited information is known about how e-cigarettes aid in smoking cessation among pregnant individuals.

Because of this, the researchers conducted a study to examine “the smoking abstinence rate among pregnant individuals who used e-cigarettes compared with NRT in a US national sample.” To do so, they compared the smoking cessation rate of NRT users during pregnancy to that of e-cigarette users during pregnancy. In their secondary analysis, they compared the smoking cessation rate of NRT users to that of 2 e-cigarette subgroups, the exisiting e-cigarette user group and the new e-cigarette user group; they placed individuals who began using e-cigarettes before pregnancy in the existing group and those who began during pregnancy in the new group.

The researchers conducted their study using phase 8 of the US Pregnancy Risk Assessment Monitoring System (PRAMS), which collected data between 2016 and 2020. Covering approximately 83% of all US births, “PRAMS is an ongoing state-level, population-based, surveillance system first administered in 1987” that uses both mail and telephone surveys to collect information on maternal attitudes, behaviors, and experiences before, during, and shortly after pregnancy, the study authors noted.

Pregnant woman in a hospital gown | Image credit: WavebreakMediaMicro - stock.adobe.com

The total sample size was 206,080 individuals, which the researchers narrowed down using specific inclusion criteria; they only included pregnant individuals who smoked combustible cigarettes within 3 months before pregnancy and used either e-cigarettes or NRT during pregnancy.

Ultimately, their population consisted of 1329 pregnant individuals, 952 of whom had an annual household income of $48,000 or less (81.5%), 766 who were non-Hispanic White individuals (79.8%), 759 older than age 25 (60.2%), and 781 who had a high school education level or lower (61.4%). Based on answers to related PRAMS questions, the population included 890 existing e-cigarette users (67.0%), 372 NRT users (28.0%), and 67 new e-cigarette users (5.0%).

The researchers found that, when comparing the 372 individuals who used NRT during pregnancy to the 67 individuals who used e-cigarettes, those who used e-cigarettes had a higher smoking abstinence rate in late pregnancy (adjusted odds ratio [aOR], 2.47; 95% CI, 1.17-5.20; P = .01). In the secondary analysis, they found that the 446 individuals who started using e-cigarettes before pregnancy had a higher smoking abstinence rate than the 67 NRT users (aOR, 2.61; 95% CI, 1.23-5.51; P = .01). On the other hand, the 10 individuals who began using e-cigarettes during pregnancy had a similar smoking abstinence rate in late pregnancy compared with the 67 NRT users (aOR, 1.13; 95% CI, 0.22-5.87; P = .88).

Overall, their findings showed that individuals who used e-cigarettes had a higher smoking abstinence rate in late pregnancy than those who used NRT, especially for those who began using e-cigarettes before pregnancy. Based on these findings, the researchers explained that replacing cigarettes with e-cigarettes during pregnancy may be a viable strategy for harm reduction.

The researchers also acknowledged their study’s limitations, one being the small sample size, as it may have produced unreliable results with larger confidence intervals. Also, only 8 of 47 states participating in PRAMS collect information on NRT use during pregnancy; this may limit the generalizability of their results.

With these limitations in mind, the researchers explained that randomized clinical trials are needed to “overcome the limitations of lack of data from most recent years (2021-2023), the incomplete exposure measures (especially NRT), and residual confounding effects.”

“Ultimately, e-cigarette products, if shown to have a lower health risk than combustible cigarette use during pregnancy, may support smoking cessation among pregnant individuals and lead to positive changes in clinical recommendations and public health policy,” the authors concluded.

Reference

Wen X, Chung MV, Liszewski KA, et al. Cigarette smoking abstinence among pregnant individuals using e-cigarettes or nicotine replacement therapy. JAMA Netw Open. 2023;6(9):e2330249. doi:10.1001/jamanetworkopen.2023.30249