AFP

This study investigated the correlation and diagnostic value of maternal serum alpha-fetoprotein (MSAFP) levels, maternal age, and body mass in early (9–13+6 weeks) and middle pregnancy (15–20+6 weeks) for predicting gestational diabetes mellitus (GDM). A total of 486 normoglycemic women and 1,290 GDM cases were analyzed. Serum levels of pregnancy-associated plasma protein A (PAPP-A), MSAFP, the free β-subunit of human chorionic gonadotropin (free β-hCG), and nuchal translucency (NT) were measured. Binary logistic regression was used to identify risk factors and calculate odds ratios (ORs). Results showed that maternal age, body mass in early and middle pregnancy, and MSAFP levels were significantly higher in the GDM group compared to the control group. Specifically, the median MSAFP level in the GDM group was 0.97 MOM (0.54–1.86), higher than in the control group at 0.92 MOM (0.51–1.78) (z = 3.159, p = 0.002). The areas under the curve (AUCs) for MSAFP, maternal age, and body mass were 0.549, 0.645, and 0.625, respectively, indicating moderate predictive power. Conversely, PAPP-A, NT, and free β-hCG showed no predictive value for GDM. These findings suggest that MSAFP, maternal age, and body mass could serve as useful biomarkers for GDM risk stratification, particularly in late pregnancy.