Background

Despite increased e-cigarette use, limited research has focused on changes in e-cigarette and combustible cigarette use around pregnancy and the subsequent effects on infant health.

Objective

This study aimed to characterize changes in e-cigarette and cigarette use from before to during pregnancy and examine their associations with small-for-gestational-age birth.

Study Design

This was a secondary data analysis of 2016–2018 data of the US Pregnancy Risk Assessment Monitoring System. We analyzed women aged ≥18 years who had a recent live birth (unweighted: n=105,438; weighted: n=5,446,900). Women were grouped on the basis of their self-reported e-cigarette and/or cigarette use 3 months before pregnancy (exclusive e-cigarette users, exclusive cigarette smokers, dual users, and nonusers) and change in e-cigarette and cigarette use during pregnancy (continuing use, quitting, switching, and initiating use). Small-for-gestational-age was defined as a birthweight below the 10th percentile for infants of the same sex and gestational age. We described the distributions of women’s sociodemographic and pregnancy characteristics in both weighted and unweighted samples. We used multivariable log-binomial regression models to estimate the relative risks for the associations between changes in e-cigarette and cigarette use during pregnancy and risk of small-for-gestational-age, adjusting for significant covariates.

Results

The rates of cessation during pregnancy were the highest among exclusive e-cigarette users (weighted percentage, 80.7% [49,378/61,173]), followed by exclusive cigarette users (54.4% [421,094/773,586]) and dual users (46.4% [69,136/149,152]). Among exclusive e-cigarette users, continued users of e-cigarettes during pregnancy had a higher risk of small-for-gestational-age than nonusers (16.5% [1849/11,206]) vs 8.8% [384,338/4,371,664]; confounder-adjusted relative risk, 1.52 [95% confidence interval, 1.45–1.60]), whereas quitters of e-cigarettes had a similar risk of small-for-gestational-age with nonusers (7.7% [3730/48,587] vs 8.8% [384,338/4,371,664]; relative risk, 0.84 [95% confidence interval, 0.82–0.87]). Among exclusive cigarette users, those who completely switched to e-cigarettes during pregnancy also had a similar risk of small-for-gestational-age with nonusers (7.6% [259/3412] vs 8.8% [384,338/4,371,664]; relative risk, 0.83 [95% confidence interval, 0.73–0.93]). Among dual users before pregnancy, the risk of small-for-gestational-age decreased from 23.2% (7240/31,208) (relative risk, 2.53 [95% confidence interval, 2.47–2.58]) if continuing use to 16.9% (6617/39,142) (relative risk, 1.88 [95% confidence interval, 1.83–1.92]) if only quitting e-cigarettes or 15.1% (1254/8289) (relative risk, 1.61 [95% confidence interval, 1.52–1.70]) if only quitting cigarettes and further to 11.2% (7589/67,880) (relative risk, 1.23 [95% confidence interval, 1.20–1.25]) if both quitting e-cigarettes and cigarettes during pregnancy, compared with nonusers.

Conclusion

Among exclusive e-cigarette users, quitting e-cigarettes during pregnancy normalized the risk of small-for-gestational-age. Among exclusive cigarette users, quitting smoking or completely switching to e-cigarettes normalized small for gestational age risk. Among dual users, smoking cessation has a greater effect than quitting e-cigarettes only, although discontinuing the use of both may lead to the greatest reduction in the risk of small-for-gestational-age.

中文翻译：

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怀孕期间电子烟和香烟使用的变化及其与小于胎龄儿出生的关系

背景

尽管电子烟的使用有所增加，但有限的研究集中在怀孕期间电子烟和可燃香烟使用的变化以及随后对婴儿健康的影响。

客观的

这项研究旨在描述从怀孕前到怀孕期间电子烟和香烟使用情况的变化，并研究它们与小于胎龄儿出生的关系。

学习规划

这是对美国妊娠风险评估监测系统2016-2018年数据的二次数据分析。我们分析了最近活产的 18 岁以上女性（未加权：n=105,438；加权：n=5,446,900）。根据女性在怀孕前 3 个月自我报告的电子烟和/或香烟使用情况（专门使用电子烟、专门吸烟者、双重使用者和非使用者）以及妊娠期间电子烟和香烟使用情况的变化对女性进行分组。怀孕（继续使用、戒断、转换和开始使用）。小于胎龄的定义是同性别同胎龄的婴儿出生体重低于第 10 个百分位。我们描述了加权和未加权样本中女性社会人口统计学和怀孕特征的分布。

结果

怀孕期间戒烟率在专门电子烟使用者中最高（加权百分比，80.7% [49,378/61,173]），其次是专门吸烟者（54.4% [421,094/773,586]）和双重使用者（46.4% [69,136]）。 /149,152]）。在仅电子烟使用者中，怀孕期间持续使用电子烟的儿童出现小于胎龄儿的风险高于不使用者（16.5% [1849/11,206]）和 8.8% [384,338/4,371,664]；混杂因素调整后的相对风险为 1.52 [95% 置信区间，1.45–1.60]），而电子烟戒烟者与非电子烟戒烟者的小于胎龄风险相似（7.7% [3730/48,587] vs 8.8%） [384,338/4,371,664]；相对风险，0.84 [95% 置信区间，0.82–0.87]）。在独家卷烟使用者中，那些在怀孕期间完全改用电子烟的人也与不使用电子烟的人有类似的小于胎龄的风险（7.6% [259/3412] vs 8.8% [384,338/4,371,664]；相对风险，0.83 [95% 置信度]区间，0.73–0.93]）。在怀孕前双重使用者中，如果继续使用，小于胎龄的风险从 23.2% (7240/31,208)（相对风险，2.53 [95% 置信区间，2.47–2.58]）下降到 16.9% (6617/ 39,142)（相对风险，1.88 [95% 置信区间，1.83–1.92]）如果仅戒掉电子烟，或 15.1% (1254/8289)（相对风险，1.61 [95% 置信区间，1.52–1.70]）如果仅戒烟与不吸烟者相比，如果在怀孕期间同时戒掉电子烟和香烟，则戒烟率进一步提高到 11.2% (7589/67,880)（相对风险，1.23 [95% 置信区间，1.20–1.25]）。6% [259/3412] vs 8.8% [384,338/4,371,664]；相对风险，0.83 [95% 置信区间，0.73–0.93]）。在怀孕前双重使用者中，如果继续使用，小于胎龄的风险从 23.2% (7240/31,208)（相对风险，2.53 [95% 置信区间，2.47–2.58]）下降到 16.9% (6617/ 39,142)（相对风险，1.88 [95% 置信区间，1.83–1.92]）如果仅戒掉电子烟，或 15.1% (1254/8289)（相对风险，1.61 [95% 置信区间，1.52–1.70]）如果仅戒烟与不吸烟者相比，如果在怀孕期间同时戒掉电子烟和香烟，则戒烟率进一步提高到 11.2% (7589/67,880)（相对风险，1.23 [95% 置信区间，1.20–1.25]）。6% [259/3412] vs 8.8% [384,338/4,371,664]；相对风险，0.83 [95% 置信区间，0.73–0.93]）。在怀孕前双重使用者中，如果继续使用，小于胎龄的风险从 23.2% (7240/31,208)（相对风险，2.53 [95% 置信区间，2.47–2.58]）下降到 16.9% (6617/ 39,142)（相对风险，1.88 [95% 置信区间，1.83–1.92]）如果仅戒掉电子烟，或 15.1% (1254/8289)（相对风险，1.61 [95% 置信区间，1.52–1.70]）如果仅戒烟与不吸烟者相比，如果在怀孕期间同时戒掉电子烟和香烟，则戒烟率进一步提高到 11.2% (7589/67,880)（相对风险，1.23 [95% 置信区间，1.20–1.25]）。

结论

在专门使用电子烟的人中，怀孕期间戒掉电子烟可以使小于胎龄的风险正常化。在只吸烟的人中，戒烟或完全改用电子烟的孕龄风险正常化较小。在双重使用者中，戒烟比仅戒电子烟的效果更大，尽管停止使用两者可能会最大程度地降低小于胎龄的风险。