Objective
To compare pregnancy outcomes of women with Gestational Diabetes Mellitus (GDM) and those without GDM [ADIPS 1998 diagnostic criteria].
Methods
A retrospective observational study of all births at Monash Health from 2009 to 2013 (n=38374) recorded in the longitudinal Birthing Outcomes System database was conducted. Antenatal characteristics, maternal and neonatal outcomes for those with ADIPS GDM (n=3018) and without ADIPS GDM (n=35356) were captured.
Pregnancy outcomes were presented as rates occurring over the five year period. Multivariable regression analysis was used to detect associations between GDM and adverse pregnancy outcomes, adjusting for potential confounders including maternal age, baseline BMI, country of birth, gravidity, past history of GDM, and family history of diabetes.
Results
Women with GDM were older (6.9% versus 3.5% age ≥40, p<0.001) and were more overweight at baseline (55.8% vs 45.3% BMI ≥ 25, p<0.001) compared to those without GDM. Thirty percent of women with GDM required insulin therapy. Rates of gestational hypertension, pre-eclampsia, pre-term delivery, macrosomia, shoulder dystocia and neonatal respiratory distress were similar between groups. Women with GDM had higher rates of induction of labour (30.7% vs 20.9%, p<0.001) and caesarean section (35% vs 26.9%, p<0.001) than those without GDM. Neonates of women with GDM had more hypoglycaemia (10.4% vs 4.7%, p<0.001), hyperbilirubinaemia (19.4% vs 17.0%, p<0.001) and required special care nursery admission (30.8% vs 19.4%, p<0.001) more frequently than those without GDM. Pregnancies with GDM had lower rates of stillbirth (0.4% vs 1.2%, p<0.001) and neonatal death (death prior to hospital discharge 0.1% vs 0.5%, p<0.001) compared to those without GDM.
Conclusions
Women with GDM have higher rates of obstetric intervention, and adverse neonatal outcomes of hypoglycaemia, hyperbilirubinaemia and special care nursery admission. However, pregnancies with GDM have lower rates of stillbirth and neonatal death.