Antenatal hemoglobin A1c and risk of large-forgestational-age infants in a multi-ethnic cohort of women with gestational diabetes

Summary Correspondence: Jodie Katon, Department ofEpidemiology, University ofWashington, Box 357236,Seattle, WA 98195, USA.E-mail:jkaton@u.washington.edu Katon J, Reiber G, Williams MA, Yanez D, Miller E. Antenatal haemoglobin A1c andrisk of large-for-gestational-age infants in a multi-ethnic cohort of women with gesta-tional diabetes. Paediatric and Perinatal Epidemiology 2012; ††: ††–††.Gestational diabetes mellitus (GDM) is a risk factor for delivering a large-for-gestational-age (LGA) infant. Haemoglobin A1c (A1C) is an indicator of glycaemiccontrol. The objective of this study was to test whether higher A1C quartile at the timeof diagnosis of GDM is associated with increased risk of delivering a LGA or mac-rosomic infant. Women with singleton pregnancies treated for GDM at a large diabetesand pregnancy programme located in Charlotte, North Carolina, were eligible forinclusion in this retrospective cohort study. Clinical information, including A1C atdiagnosis, treatment, prior medical and obstetric history, and birth data wereabstracted from medical records. LGA was defined as birthweight >90th percentile forgestational age and sex and macrosomia as birthweight >4000 g. Logistic regressionwas used to analyse the association of A1C at GDM diagnosis with risk of deliveringLGA or macrosomic infants. This study included 502 women. Prevalences of LGA andmacrosomia were 4% and 6% respectively. After adjustment there was no detectabletrend of increased risk for LGA (