Neonatal hypoglycaemia is a common complication of pregnancies complicated by GDM. The modified Pedersen Hypothesis suggests that in maternal hyperglycaemia, excess glucose crosses the placenta stimulating the fetal pancreas into hyperinsulinemia. A direct consequence of hyperinsulinemia is neonatal hypoglycaemia. The aim of this project was to conduct a retrospective clinical audit of pregnancies complicated by gestational diabetes from Macarthur Diabetes Clinic within the last 3 years and examine modifiable and non-modifiable factors such as antenatal care, maternal demographics, diabetes management and obstetric complications associated with severe neonatal hypoglycaemia. Neonatal hypoglycaemia was defined as <1.1 mmol/l if <37 weeks gestation and <1.7 mmol/l if 37+ weeks. Among the 555 women, 21 (3.8%) had births documented as being complicated by severe neonatal hypoglycaemia. Mean age and pre-pregnancy body mass index were not significantly different, but fasting glucose on the oral glucose tolerance test was significantly higher in index cases (5.4±0.1 vs 5.1±0.1 mmol/l; p=0.026) who were also born earlier (36.9±0.5 38.7±0.1 weeks p<0.001) with lower birthweight (2841±127 vs 3312±25g p<0.001). Women with births complicated by neonatal hypoglycaemia were non-significantly more likely to be treated with insulin (38% vs 26%) with higher insulin doses (31±7 vs 25±2 units). Metformin therapy was taken by 13% v 10% (NS). We conclude that pregnancies complicated by severe neonatal hypoglycaemia are more hyperglycaemic when diagnosed, and that therapy has been insufficient to prevent this complication. More births occurred prematurely in the pregnancies complicated by neonatal hypoglycaemia, which would have also been an exacerbating factor.