273: Excessive fetal growth within appropriate-for-gestational-age affects neonatal hypoglycemia and macrosomia in gestational diabetes mellitus

Abstract

Gestational diabetes mellitus (GDM) affects large-for-gestational-age and macrosomia that are associated with obstetrical and neonatal complications. However, neonatal outcome of appropriate-for-gestational-age (AGA) fetus from GDM pregnancy has not been fully understood. The purpose of this study is to evaluate the association between interval changes of fetal growth and neonatal outcome in AGA fetus of GDM pregnancy. It was a retrospective case-control study of 660 singleton pregnancies with GDM in 4 tertiary care hospitals from 2006 to 2013 in Korea. We obtained clinical and fetal biometric parameters. Estimated fetal weight (EFW) was measured at the time of GDM diagnosis (2nd trimester) and within 2 weeks before delivery (3rd trimester). Both < 10th and >90th centile for gestation groups were excluded for including AGA. All measured EFWs were divided in four centile groups (10-25th, 25-50th, 50-75th and 75-90th centile for gestation). Interval changes of biometric parameters between 2nd and 3rd trimesters were determined. All included pregnancies were divided in three groups by change of centile; decrease, no change and increase groups. We evaluated obstetrical and neonatal outcomes such as cephalo-pelvic disproportion, macrosomia, low Apgar score, neonatal serum glucose and respiratory distress in three groups. Neonatal serum glucose (p=0.009), incidence of hypoglycemia (p=0.012) and macrosomia (p< 0.001) were significantly different among three groups. Compared to centile decrease group, centile increase group showed low level of neonatal serum glucose (70.7 ± 1.03mg/dl vs 61.65 ± 4.06mg/dl, p=0.009), high incidence of hypoglycemia (odds ratio [OR] 2.559; 95% CI 1.266-5.172, p=0.007) and macrosomia (OR 7.839; 95% 3.272-18.781, p< 0.001). In this study, excessive fetal growth within a range of AGA during GDM pregnancy represented neonatal low glycemic status and higher incidence of macrosomia. Therefore, even though EFW is included in AGA, consideration of serial growth pattern is necessary to evaluate neonatal outcome and predict macrosomia in GDM pregnancy.