There is limited data on the optimal screening method for early gestational diabetes. We sought to determine whether an early A1c or two-step glucose tolerance test (GTT) better identified pregnancies with adverse outcomes.
This was a retrospective cohort study of patients who met the American College of Obstetricians and Gynecologist’s criteria for early screening and delivered between 2017-2020 at a single center. Patients with a A1c and/or the two-step (1-hr GTT, followed by 3-hr GTT) method at <20 weeks were included. Adverse pregnancy outcomes were compared between patients with A1c ≥5.7% and those with A1c <5.7% using univariate and multiple variable analyses. In a similar fashion, patients with a positive or negative two-step method were compared.
There were 883 patients who received either a A1c (N=259) or underwent the two-step method (N=624). Patients with an A1c ≥5.7% had higher rates of macrosomia (21.6% vs. 5.1%) but lower rates of neonatal hypoglycemia (3.4% vs. 14.7%) than those with a A1c <5.7%. Patients who had a positive two-step method had higher rates of cesarean delivery (56.1% vs. 34.5%) and preterm delivery <32 weeks (12.2% vs. 2.2%).
A1c ≥5.7% in early pregnancy was associated with higher rates of macrosomia compared to those with an A1c <5.7%. Despite treatment, screening positive by an early two-step method had higher rates of cesarean delivery and preterm delivery <32 weeks than those who tested negative by the same method.
K.C.Bodycot: None. R.Huang: None. H.B.Al-kouatly: None. R.Mclaren: None.
