Related Experiment Video
Updated: Jun 27, 2026
Quantitating Iron Transport Across the Mouse Placenta In Vivo Using Nonradioactive Iron Isotopes
Published on: May 10, 2022
Early-pregnancy serum iron as a nutrition-related clinical laboratory indicator for preeclampsia risk stratification:
Sijia Fang1, Qianlan Zhang2, Ying Chen1
1Shanghai Jiai Genetic and IVF Institute, Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China.
Background:
Nutrition-related clinical laboratory indicators are valuable for risk assessment, early identification, and precision management in obstetric and gynecologic diseases. Serum iron, a commonly used laboratory marker reflecting iron metabolism status, has shown inconsistent associations with preeclampsia (PE).
Objective:
To investigate the association between early-pregnancy serum iron levels and the risk of PE, and to evaluate their associations with low birth weight, cesarean delivery, and preterm birth.
Methods:
This single-center retrospective cohort study included 37,643 pregnant women. Early-pregnancy serum iron level was the exposure variable, PE the primary outcome, and low birth weight, cesarean delivery, and preterm birth secondary outcomes. Logistic regression models (non-adjusted, Adjust I, and Adjust II) assessed associations between serum iron and each outcome. Smooth curve fitting illustrated the relationship between serum iron and PE risk. Stratified analyses by age, BMI, and parity, along with interaction analysis, evaluated the robustness of the association.
Results:
Serum iron levels were lower in the PE group than in the non-PE group (20.45 ± 6.16 vs. 21.32 ± 6.11 μmol/L, p < 0.001). Curve fitting, adjusted for age, BMI, and hemoglobin, showed that PE risk generally decreased with increasing serum iron. In the non-adjusted model, each 10 μmol/L increase in serum iron was associated with a 21% reduction in PE risk (OR = 0.79, 95% CI: 0.73-0.85, p < 0.0001); In the fully adjusted model, each 10 μmol/L increase in serum iron was associated with a lower risk of PE (OR = 0.89, 95% CI: 0.82-0.97, p = 0.0071). For other outcomes, higher serum iron was significantly associated with lower risk of cesarean delivery, whereas no stable significant associations were observed for low birth weight or preterm birth. Stratified analyses showed the inverse association between serum iron and PE was more evident among women aged <35 years, those with BMI < 24 kg/m2, and primiparous women; however, interaction tests for age, BMI, and parity were not statistically significant.
Conclusion:
Higher early-pregnancy serum iron levels were significantly associated with lower risk of PE, although its clinical utility still requires further validation in prospective studies.
