Background:
Diabetes in pregnancy is an increasingly common challenge. Previous local data highlighted high rates of congenital malformations and macrosomia, underscoring the importance of preconception and antenatal planning to optimise maternal-foetal outcomes1.
Aim:
To assess trends and differences in maternal and neonatal outcomes among pregnancies affected by pregestational diabetes from 2021–2024.
Method:
We conducted a retrospective audit of women with pregestational diabetes attending Campbelltown Diabetes in Pregnancy Clinic. Outcomes were summarised as median (IQR) and compared between Type 1 diabetes (T1DM) and Type 2 diabetes (T2DM) using the Kruskal-Wallis test.
Results:
233 pregnancies (197 (84.5%) live births, 22 (9.4%) miscarriages, 3 (1.3%) stillbirths) were analysed. T2DM accounted for 62.6%, T1DM 34.4%: Caucasian (38.3%), South Asian (18.1%), Māori/Pacific Islander (17.6%). Median booking BMI was higher (p<0.001) in T2DM (33.3kg/m², IQR 30.3-39.0) vs T1DM (29.1kg/m², IQR 25.8-32.4). Median first HbA1c was 6.8% (IQR 6.1-8.0, T1DM=T2DM, p=0.69) and median first visit gestation was 12 weeks (IQR 10-15, T1DM=T2DM, p=0.18). High dose folate in first trimester was documented in 43.8%.
Median gestation at delivery was 37⁺4 weeks (IQR 37⁺⁰-39⁺5). Median birthweight was 3345g, higher (p<0.001) in T1DM (3535g) than T2DM (3223g). Macrosomia (birthweight>4000g) was more common in T1DM (23.9% vs 10.3%, p=0.021). Neonatal hypoglycaemia occurred in 44.4% (T1DM=T2DM, p=0.47), of which 57.0% required intravenous dextrose. Major and minor congenital malformations occurred in 4.0% and 8.6%.
Conclusion:
High rates of malformations, hypoglycaemia and macrosomia persist, reiterating the importance of preconception planning and optimal glycaemic management to improve outcomes.