Cadmium levels in maternal blood, placenta, and cord blood in relation to preeclampsia and fetal growth: a case-control study in China

This study aims to delineate the levels of Cd exposure in maternal blood, placenta, and cord blood, and to explore the association between Cd levels and the risk of preeclampsia (PE), as well as its potential impact on fetal growth among affected individuals. A case-control study was performed at the First Hospital of Shanxi Medical University, involving 373 pregnant women diagnosed with PE and 485 controls. Cd was measured in maternal blood, placenta, and cord blood using ICP-MS. The association between Cd and birth weight z-score was analyzed by multivariate linear regression. Logistic regression analysis was used to investigate the relationships between Cd and the risk of PE, and Cd and the risk of fetal growth. The concentration of Cd in the placenta was higher than that in maternal blood and cord blood. The highest tertile of placental Cd was identified as a risk factor for PE (OR = 2.704, 95% CI: 1.865, 3.921). Among pregnant women with PE, higher levels of Cd exposure in the placenta were negatively associated with birth weight z-scores (per doubling: beta = -0.134, 95% CI: -0.264, -0.004), and the highest tertile of placental Cd was associated with an elevated risk of SGA (OR = 2.103, 95% CI: 1.164, 3.801). Furthermore, an interaction between Cd and PE was identified. In conclusion, Cd can accumulate in the placenta of pregnant women, and high placental Cd exposure not only increases the risk of PE but also exacerbates the risk of SGA outcome in PE pregnant women.