Prenatal chromium exposure and risk of preterm birth: a cohort study in Hubei, China

• Main Authors: Xinyun Pan, Jie Hu, Wei Xia, Bin Zhang, Wenyu Liu, Chuncao Zhang, Jie Yang, Chen Hu, Aifen Zhou, Zhong Chen, Jiangxia Cao, Yiming Zhang, Youjie Wang, Zheng Huang, Bin Lv, Ranran Song, Jianduan Zhang, Shunqing Xu, Yuanyuan Li
• Format: Article
• Language: English
• Published: Nature Publishing Group 2017-06-01
• Series: Scientific Reports
• Online Access: https://doi.org/10.1038/s41598-017-03106-z

Abstract Few studies have investigated the association of environmental chromium exposure and preterm birth in general population. This study was designed to investigate whether maternal chromium exposure during pregnancy is associated with reduced gestational age or risk of preterm birth using the data from Healthy Baby Cohort study conducted in Hubei, China between 2012 and 2014 (n = 7290). Chromium concentrations in maternal urine samples collected at delivery were measured with inductively coupled plasma mass spectrometry. Tertiles of chromium concentrations was negatively associated with gestational age in multivariable linear regression analyses [β (95% CI): low = reference; middle = −0.67 days (−1.14, −0.20); high = −2.30 days (−2.93, −1.67); p trend <0.01]. Logistic regression analyses also indicated that higher maternal chromium [adjusted odds ratio (OR) (95% CI): 1.55(0.99, 2.42) for the medium tertile; 1.89(1.13, 3.18) for the highest tertile; p trend <0.01] was associated with increased risk of preterm birth. The associations appeared to be more pronounced in male infants (adjusted OR (95% CI): 2.54 (1.29, 4.95) for the medium tertile; 2.92 (1.37, 6.19) for the highest tertile; p trend <0.01). Our findings suggest maternal exposure to higher chromium levels during pregnancy may potentially increase the risk of delivering preterm infants, particularly for male infants.