Division of Epidemiology and Biostatistics, School of Public Health, University of Illinois Chicago, Chicago, IL 60612, United States.
Environmental Protection Agency, Washington, DC 20004, United States.
Environ Int. 2021 Feb;147:106373. doi: 10.1016/j.envint.2020.106373. Epub 2021 Jan 12.
Prenatal exposure to metals may play an important role in fetal growth. However, the epidemiologic evidence for certain metals is sparse, and most of the existing research has focused on evaluating single metals in highly exposed target populations.
We evaluated associations of cadmium, lead, manganese, selenium, and total mercury exposures during pregnancy with fetal growth using data from mother-infant pairs participating in the National Children's Study.
Prenatal metal exposures were measured using maternal blood collected from 6 to 32 weeks of gestation. Birth outcomes, including gestational age, birthweight, birth length, head circumference, and ponderal index, were ascertained through physical measurement at birth or abstraction from medical records. Regression coefficients and their 95% confidence intervals were estimated from multivariable linear regression models in the overall study population as well as among male and female infants. We further evaluated pairwise metal-metal interactions.
Sex-specific associations were observed for lead, with inverse associations for birthweight, birth length, head circumference, and gestational age observed only among female infants. Sex-specific associations were also observed for selenium, with a positive association for birthweight observed among male infants; selenium was also positively associated with ponderal index and inversely associated with birth length among female infants. Overall, total mercury was inversely associated with birthweight and ponderal index, and the association with birthweight was stronger among female infants. No significant associations were observed with cadmium and manganese. In the metal-metal interaction analyses, we found evidence of a synergistic interaction between lead and total mercury and antagonistic interaction between selenium and total mercury with selected birth outcomes.
Our findings suggest that prenatal exposure to metals may be related to birth outcomes, and infant sex may modify these associations.
产前暴露于金属可能对胎儿生长发育起着重要作用。然而，某些金属的流行病学证据稀缺，并且大多数现有研究都集中在评估高暴露目标人群中的单一金属。
我们利用参与国家儿童研究的母婴对的数据，评估了妊娠期间镉、铅、锰、硒和总汞暴露与胎儿生长的关联。
使用妊娠 6 至 32 周采集的母亲血液来测量产前金属暴露。通过出生时的体格测量或从病历中提取，确定出生结局，包括胎龄、出生体重、出生身长、头围和体重指数。从总体研究人群以及男性和女性婴儿的多变量线性回归模型中估计回归系数及其 95%置信区间。我们进一步评估了金属-金属相互作用。
在女性婴儿中观察到铅的性别特异性关联，仅观察到与出生体重、出生身长、头围和胎龄呈负相关。在男性婴儿中观察到硒的性别特异性关联，与出生体重呈正相关；在女性婴儿中，硒与体重指数呈正相关，与出生身长呈负相关。总体而言，总汞与出生体重和体重指数呈负相关，且这种与出生体重的关联在女性婴儿中更强。在镉和锰方面未观察到显著关联。在金属-金属相互作用分析中，我们发现铅和总汞之间存在协同相互作用，以及硒和总汞与某些出生结局之间存在拮抗相互作用的证据。
我们的研究结果表明，产前金属暴露可能与出生结局有关，而婴儿性别可能会调节这些关联。
