The correlation between serum magnesium, phosphorus, and calcium levels during pregnancy and the risk of gestational diabetes mellitus as well as adverse pregnancy outcomes.

Introduction: This retrospective cohort study included 700 pregnant women who underwent antenatal check-ups and delivered at the Fourth Hospital of Shijiazhuang from January 2022 to December 2023, aiming to investigate the associations of second°trimester serum magnesium, phosphorus, and calcium with adverse pregnancy outcomes including gestational diabetes mellitus (GDM), anemia, and preterm birth. Mineral indicators were measured at 24-28 weeks of gestation, and baseline data were collected. Methods: Mann-Whitney U test was adopted to compare the serum mineral levels among women with different pregnancy outcomes, multivariable logistic regression and ROC curve analysis was utilized to further explore the correlations. Results: After adjusting for potential confounders, magnesium, phosphorus, and calcium levels were correlated with GDM risk, with magnesium and calcium exerting statistically significant protective effects against GDM while high phosphorus serving as a statistically significant GDM risk factor. High calcium was also negatively associated with the risks of anemia and preterm birth whereas high phosphorus was positively linked to preterm birth risk. Discussion: These findings demonstrate that second-trimester serum magnesium, phosphorus, and calcium levels are associated with GDM, providing clinical evidence for glycemic control interventions and individualized nutritional guidance during pregnancy.