Background Selenium (Se), an essential trace mineral, has been implicated in preterm birth (PTB). We aimed to determine the association of maternal Se concentrations during pregnancy with PTB risk and gestational duration in a large number of samples collected from diverse populations. Methods Gestational duration data and maternal plasma or serum samples of 9946 singleton live births were obtained from 17 geographically diverse study cohorts. Maternal Se concentrations were determined by inductively coupled plasma mass spectrometry analysis. The associations between maternal Se with PTB and gestational duration were analysed using logistic and linear regressions. The results were then combined using fixed-effect and random-effect meta-analysis. Findings In all study samples, the Se concentrations followed a normal distribution with a mean of 93.8 ng/mL (SD: 28.5 ng/mL) but varied substantially across different sites. The fixed-effect meta-analysis across the 17 cohorts showed that Se was significantly associated with PTB and gestational duration with effect size estimates of an OR=0.95 (95% CI: 0.9 to 1.00) for PTB and 0.66 days (95% CI: 0.38 to 0.94) longer gestation per 15 ng/mL increase in Se concentration. However, there was a substantial heterogeneity among study cohorts and the random-effect meta-analysis did not achieve statistical significance. The largest effect sizes were observed in UK (Liverpool) cohort, and most significant associations were observed in samples from Malawi. Interpretation While our study observed statistically significant associations between maternal Se concentration and PTB at some sites, this did not generalise across the entire cohort. Whether population-specific factors explain the heterogeneity of our findings warrants further investigation. Further evidence is needed to understand the biologic pathways, clinical efficacy and safety, before changes to antenatal nutritional recommendations for Se supplementation are considered. Data are available upon reasonable request.

中文翻译：

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母亲产前硒浓度与早产的关系：一项多国荟萃分析

背景 硒 (Se) 是一种必需的微量矿物质，与早产 (PTB) 有关。我们的目的是确定怀孕期间母体硒浓度与从不同人群收集的大量样本中的 PTB 风险和妊娠持续时间之间的关联。方法 从 17 个地理上不同的研究队列中获得 9946 例单胎活产的妊娠持续时间数据和母体血浆或血清样本。通过电感耦合等离子体质谱分析确定母体硒浓度。使用逻辑回归和线性回归分析母体硒与 PTB 和妊娠持续时间之间的关联。然后使用固定效应和随机效应荟萃分析合并结果。结果 在所有研究样本中，硒浓度服从均值为 93 的正态分布。8 ng/mL（标准差：28.5 ng/mL），但在不同地点之间差异很大。跨 17 个队列的固定效应荟萃分析表明，Se 与 PTB 和妊娠持续时间显着相关，对于 PTB 和 0.66 天（95% CI：硒浓度每增加 15 ng/mL，妊娠时间延长 0.38 至 0.94)。然而，研究队列之间存在很大的异质性，随机效应荟萃分析未达到统计学意义。在英国（利物浦）队列中观察到最大的效应量，在来自马拉维的样本中观察到最显着的关联。解释 虽然我们的研究在某些地点观察到母体硒浓度与 PTB 之间具有统计学意义的关联，但这并未在整个队列中推广。人群特定因素是否可以解释我们研究结果的异质性值得进一步调查。在考虑改变产前补充硒的营养建议之前，需要进一步的证据来了解生物学途径、临床疗效和安全性。可根据合理要求提供数据。