Exposure to multiple metals, maternal glucose homeostasis and gestational diabetes mellitus: A prospective cohort study.

Humans are widely exposed to environmental pollutants, affecting glucose homeostasis and resulting in gestational diabetes mellitus (GDM). However, studies about joint exposure of heavy metals and glucose homeostasis during pregnancy are limited and with the inconsistent findings. Blood concentrations of mercury (Hg), arsenic (As), lead (Pb), copper (Cu), vanadium (V), beryllium, strontium, zinc, nickel, cobalt, chromium, titanium, aluminum, antimony and iron were measured using inductively coupled plasma-mass spectrometry among 251 GDM women and 502 matched controls from Taiyuan, China. Multivariate logistic regression models, Bayesian kernel machine regression (BKMR), weighted quantile sum (WQS) regression, and quartile g-computation regression (QGCOMP) were used to assess the associations between metals exposures, maternal glucose homeostasis and GDM. An increased risk of GDM was associated with As, Pb and Hg in 1st trimester. Furthermore, exposure to Cu and Hg were associated with an elevated risk of GDM in 2nd trimester. The BKMR, WQS regression, and QGCOMP all found metals mixture exposure, predominated by Hg, As, and Pb in 1st trimester, was positively associated with GDM. The WQS regression revealed a positive correlation between metals characterized by Hg, Cu and As and GDM in 2nd trimester. The risk on GDM from joint metals was predominated by Hg, As, and Pb in 1st trimester, and by Hg, Cu, and As in 2nd trimester.