Maternal occupational exposure to noise: prevalence, maternal effects and infant outcomes in the National Birth Defects Prevention Study, 1997–2011
基于美国全国出生缺陷预防研究数据，分析母亲孕期职业噪声暴露与妊娠糖尿病、高血压、早产及小于胎龄儿的关系，发现中等噪声暴露增加小于胎龄儿风险，低噪声暴露反而降低风险。
OBJECTIVES: We investigated associations between occupational noise and gestational diabetes mellitus, pregnancy-related hypertension (including pre-eclampsia/eclampsia), preterm birth and small for gestational age (SGA) infants. METHODS: Data were analysed for 7889 singleton, live-born infants without major birth defects or chromosomal disorders and their mothers from the National Birth Defects Prevention Study from 1997 to 2011. Typical maternal occupational noise exposure in all jobs held from 1 month prior to conception through the end of pregnancy was estimated by expert rater and categorised as quiet (<60 A-weighted decibels (dBA)), low (60-75 dBA), moderate (76-84 dBA) or loud (>85 dBA). Multiple logistic regression was used to estimate associations (adjusted ORs and 95% CIs) between noise exposure levels and outcomes. RESULTS: Approximately 77.4% of pregnant workers had quiet levels of occupational noise exposure, 11.0%, 10.1% and 1.5% had low, moderate and loud exposure levels, respectively. Compared with quiet levels of noise, pregnant workers exposed to low levels of noise had decreased odds of delivering an SGA infant (adjusted OR (aOR)=0.72; 95% CI 0.53 to 0.99) and those exposed to moderate levels had increased odds of delivering an SGA infant (aOR=1.37; 95% CI 1.05 to 1.77). No other significant associations were observed. CONCLUSION: Maternal occupational noise exposure below the 85 dBA threshold recognised as hazardous may be associated with SGA among infants. Elevated point estimates (>1) were observed for the highest noise exposure category and all outcomes, though CIs were wide and statistical significance was not attained. Further research is warranted to address existing knowledge gaps.