Oral Presentation Australian and New Zealand Obesity Society Annual Scientific Conference 2024

The impact of obesity on pregnancy outcomes in women with type 1 and type 2 diabetes across the NSW population (#101)

Xavier XR Rickard 1 2 , Matilda ML Longfield 2 3 , Sarah SG Glastras 1 2 3
  1. Northern Precinct, Sydney Medical School, University of Sydney, Sydney, NSW, Australia
  2. Kolling Institute, Stanmore, NSW, Australia
  3. Department of Diabetes, Endocrinology and Metabolism, Royal North Shore Hospital, Sydney, NSW, Australia

Background: Women with type 1 (T1D) and type 2 (T2D) diabetes experience higher rates of adverse pregnancy outcomes than those without diabetes, even with optimal glycaemic control. Diabetes type and body mass index (BMI) are thought to be driving factors behind this disparity, but robust evidence is lacking.

Aim: To investigate the role of maternal obesity on pregnancy outcomes in women with T1D and T2D diabetes.

Methods: We retrospectively analysed data from singleton births of nulliparous mothers with T1D and T2D from 2016-2020 in New South Wales. Incidences of perinatal outcomes were compared across diabetes type. Logistic regression analyses explored the impact of BMI and diabetes type on these outcomes, adjusting for maternal covariates.

Results: 1478 pregnancies were included in this study. Of these, 568 were in women with T1D and 910 in T2D. Age, duration of diabetes, maternal BMI, pre-existing hypertension, smoking status and region of birth were significantly different between groups (p<0.05). Compared to T2D pregnancies, T1D pregnancies had increased odds of various adverse perinatal outcomes, such as preeclampsia (OR=1.63, CI 1.02-2.60, p=0.04), caesarean section (OR=2.30, CI 1.75-3.02, p<0.01), preterm birth (OR=3.67, CI 2.72-4.96, p<0.01), LGA (OR=5.14, CI 3.88-6.80, p<0.01), neonatal hypoglycaemia (OR=4.21, CI 3.32-5.34, p<0.01) and stillbirth (OR=2.85, CI 1.06-7.71, p=0.04). Obesity was not a significant predictor for any adverse outcome in T1D. In women with T2D, those with obesity had increased odds of gestational hypertension (OR=5.88, CI 1.38-25.15, p=0.02), postpartum haemorrhage (OR=1.95, CI 1.18-3.23, p<0.01), caesarean section (OR=2.29, CI 1.59-3.30, p<0.01), LGA (OR=1.82, CI 1.13-2.93, p=0.01) and neonatal hypoglycaemia (OR=1.53, CI 1.02-2.30, p=0.04).

Conclusions: Women with T1D have higher odds of adverse perinatal outcomes compared to T2D. Obesity increases the risk of adverse outcomes in women with T2D but not T1D. Targeted interventions for managing obesity in pregnant women with T2D are essential to improve outcomes.