Contributing Factors to Perinatal Outcome in Pregnancies with Gestational Diabetes-What Matters Most? A Retrospective Analysis

Abstract

The aim of diabetes care of pregnant women with gestational diabetes mellitus (GDM) is to attain pregnancy outcomes including rates of large-for-gestational-age (LGA) newborns, pre-eclampsia, C-sections (CS) and other neonatal outcomes similar to those of the non-GDM pregnant population. Obesity and excessive weight gain during pregnancy have been shown to also impact perinatal outcome. Since GDM is frequently associated with elevated body mass index (BMI), we evaluated the impact of maternal prepregnancy BMI, development of GDM and gestational weight gain (GWG) during pregnancy on perinatal outcome. We compared 614 GDM patients with 5175 non-diabetic term deliveries who gave birth between 2012 and 2016. Multivariate regression analysis was used to evaluate the independent contribution of each factor on selected perinatal outcome variables. Additionally, subgroup analysis for obese (BMI ≥ 30 kg/m²) and non-obese women (BMI < 30 kg/m²) was performed. LGA was significantly influenced by BMI, GWG and GDM, while Neonatal Intensive Care Unit (NICU) admission was solely impacted by GDM. Maternal outcomes were not dependent on GDM but on GWG and prepregnancy BMI. These results remained significant in the non-obese subgroup only. Thus, GDM still affects perinatal outcomes and requires further improvement in diabetic care and patient counseling.

Keywords: C-section; NICU; body mass index; gestational diabetes; gestational weight gain; large for gestational age; obesity; perinatal outcomes.

Figure 1

Cohort composition: The final cohort consists out of 614 gestational diabetes (GDM) cases and 5175 non-GDM term deliveries. The non-GDM cohort was derived from initially 7033 singleton mother infant dyads from 2012 until 2016. All cases of stillbirths, fetal malformations, preterm deliveries (<37 weeks) and cases with incomplete data were excluded in both groups. All types of diabetes cases were excluded in the non-GDM group. ¹ Higher rate of exclusions due to missing information about deliveries ex muros.

Figure 2

Adjusted odds ratios (ORs) of perinatal complications for the non-obese and obese subgroups: large for gestational age (LGA), neonatal intensive care unit (NICU) admission, pre-eclampsia and C-Section. Results from the logistic regression models adjusted for maternal age, parity, gestational age and sex of the newborn are presented: excessive gestational weight gain (eGWG), body mass index (BMI), gestational weight gain (GWG) per kg and gestational diabetes (GDM).