Background

Preterm birth is a disease of multifactorial etiologies that has environmental, social, and maternal health components. Individual studies have shown that exposure to arsenic contaminated drinking water, child marriage, and low maternal weight gain during pregnancy contribute to preterm birth. These factors are highly prevalent and often co-exist in Bangladesh, a country in South Asia with one of the world's highest prevalences of preterm birth.

Objective

To evaluate the individual and interactive effects of prenatal arsenic exposure, child marriage, and pregnancy weight gain on preterm birth in a prospective birth cohort in Bangladesh.

Methods

During 2008–2011, we recruited 1613 pregnant women aged ≥ 18 years at ≤ 16 weeks of gestation and followed them until 1-month post-partum. We measured total arsenic in drinking water (n = 1184) and in maternal toenails (n = 1115) collected at enrollment and ≤ 1-month post-partum, respectively using inductively coupled plasma mass spectrometry. Child marriage (< 18 years old) was defined using self-report, and 2nd and 3rd trimester pregnancy weight gain was calculated using monthly records. Gestational age was determined at enrollment by ultrasound.

Results

In multivariate adjusted Poisson regression models, the risk ratios (RR) for preterm birth were 1.12 (95% CI: 1.07–1.18) for a unit change in natural log water arsenic exposure, 2.28 (95% CI: 1.76–2.95) for child marriage, and 0.64 (95% CI: 0.42–0.97) for a pound per week increase in maternal weight during the 2nd and 3rd trimesters. In stratified analysis by child marriage, pregnancy weight gain was inversely associated with preterm birth among women with a history of child marriage (RR = 0.58; 95% CI: 0.37–0.92), but not among women with no history of child marriage (RR = 86; 95% CI: 0.37–2.01). Mediation analysis revealed that both arsenic exposure and child marriage had small but significant associations with preterm birth via lowering pregnancy weight gain. Similar associations were observed when arsenic exposure was assessed using maternal toenail arsenic concentrations.

Conclusions

Reducing arsenic exposure and ending child marriage could reduce the risk of preterm birth in Bangladesh. Furthermore, enhancing nutritional support to ensure adequate weight gain during pregnancy may provide additional benefits especially for women with a history of child marriage.

中文翻译：

---

产前砷暴露，童婚和怀孕体重增加：孟加拉国与早产的关联

背景

早产是一种多病因病，具有环境，社会和孕产妇健康成分。个别研究表明，暴露于砷污染的饮用水，童婚以及孕妇在孕期体重增加较低会导致早产。这些因素非常普遍，通常在孟加拉国并存，孟加拉国是南亚早产流行率最高的国家之一。

客观的

在孟加拉国的预期出生队列中，评估产前砷暴露，童婚和怀孕体重增加对早产的个体和互动影响。

方法

在2008-2011年期间，我们招募了1613名年龄≥18岁，怀孕≤16周的孕妇，并跟踪她们直到产后1个月。我们使用感应耦合等离子体质谱法分别测量了入院时和产后≤1个月时收集的饮用水（n = 1184）和母体趾甲（n = 1115）中的总砷。使用自我报告定义童婚（<18岁），并使用月度记录计算第2和第3孕中期孕妇体重增加。妊娠年龄是通过超声检查确定的。

结果

在多元校正的Poisson回归模型中，自然对数水砷暴露的单位变化导致早产的风险比（RR）为1.12（95％CI：1.07–1.18），儿童为2.28（95％CI：1.76–2.95）婚姻，在孕中期和孕中期每周增加一磅体重，每周增加0.64（95％CI：0.42-0.97）。在通过童婚进行的分层分析中，有童婚史的妇女的怀孕体重增加与早产成反比（RR = 0.58； 95％CI：0.37-0.92），但没有童婚史的妇女则没有（早产）（RR = 86； 95％CI：0.37–2.01）。调解分析显示，砷暴露和童婚都通过降低孕妇体重增加而与早产有较小但显着的关联。

结论

减少砷暴露和结束童婚可以减少孟加拉国早产的风险。此外，加强营养支持以确保怀孕期间足够的体重增加可能会提供额外的好处，尤其是对于有童婚史的妇女。