Gestational diabetes in twin pregnancy: A predictor of adverse fetomaternal outcomes?

Aim To compare fetomaternal outcomes between GDM pregnant women with twin versus singleton pregnancies and then between women with GDM versus non-GDM twin pregnancies. Methods We performed a retrospective study including GDM pregnant women with both twin and singleton pregnancies followed in our tertiary center between 2011 and 2018. The fetomaternal characteristics of each group were compared. We then compared women with GDM twin pregnancy followed at our institution between 2011 and 2018 to non-GDM twin pregnant women giving childbirth in 2018. Results A total of 1127 GDM pregnant women were evaluated: 42 with twin pregnancy and 1085 with singleton pregnancy. Preeclampsia (14.3% vs. 3.3%, p < 0.001) and cesarean delivery (76.2% vs. 36.9%, p < 0.001) were more frequent among women with twin pregnancy. Neonatal morbidity was also more common among neonates delivered from twin pregnant women, including preterm labor (73.8% vs. 7.8%, p < 0.001), hypoglycemia (6% vs. 4.8%, p = 0.043), hyperbilirubinemia (33.3% vs. 9.0%, p < 0.001), RDS (28.6% vs. 2.7%, p < 0.001), admission in NICU (32.1% vs. 4.5%, p < 0.001) and SGA (19.0% vs. 11.0%, p = 0.001). Overall there were no significant differences in fetomaternal morbidity parameters between GDM (n = 42) versus non-GDM (n = 83) twin pregnancies, although SGA infants were more frequent in the latter group (33.9% vs. 19.0%, p = 0.014). Conclusions In GDM pregnant women, twin pregnancy seems to be associated with an increased prevalence of neonatal morbidity when compared to singleton pregnancy. On the other hand, in twin pregnancy, diagnosis of GDM does not seem to be associated with poorer fetomaternal outcomes. GDM seems to be protective for the occurrence of SGA neonates in twin pregnancies.