Risk factors and perinatal outcomes of gestational diabetes mellitus in dichorionic twin pregnancies: a retrospective cohort study

Objective To identify maternal risk factors for gestational diabetes mellitus (GDM) and to evaluate its perinatal implications in dichorionic (DC) twin pregnancies, a population in which metabolic demands and placental physiology differ substantially from singleton gestations.Methods A retrospective cohort study was conducted among 378 women with confirmed DC twin pregnancies, including 122 women with GDM and 256 without GDM, delivered at a tertiary maternal–fetal medicine center between 2018 and 2023. GDM was diagnosed using IADPSG criteria following a 75-g oral glucose tolerance test. Maternal demographic factors, conception mode, early ultrasound parameters, obstetric outcomes, and neonatal outcomes were compared between women with and without GDM using univariate analyses and multivariate logistic regression.Results Pre-pregnancy BMI ≥25 kg/m2 (adjusted OR 1.857, 95% CI 1.050–3.284) and conception via assisted reproductive technology (adjusted OR 1.608, 95% CI 1.029–2.514) independently increased the likelihood of developing GDM. Most maternal and neonatal outcomes—including preterm birth, birth weight patterns, neonatal hypoglycemia, and NICU admission—did not differ significantly between the two groups. However, GDM was associated with a higher incidence of single intrauterine fetal demise (7.4% vs. 2.7%, p = 0.036).Conclusion In DC twin pregnancies, maternal overweight and ART conception constitute significant risk factors for GDM. While many perinatal outcomes appear unaffected, the elevated risk of single fetal demise underscores the need for intensified fetal surveillance and individualized management in this high-risk population.