Oral Presentation Australian and New Zealand Obesity Society Annual Scientific Conference 2023

Obesity Magnifies the Adverse Maternal and Neonatal Outcomes Associated with Twin Gestations (98057)

Natasha Byrne 1 2 , Tessa Weir 1 2 3 4 , Sarah Glastras 1 2 4
  1. Northern Clinical School, University of Sydney, Faculty of Medicine and Health, St Leonards, Sydney, NSW, Australia
  2. Kolling Institute, St Leonards, Sydney, NSW, Australia
  3. Nepean Hospital, Kingswood, NSW, Australia
  4. Department of Diabetes, Endocrinology & Metabolism, Royal North Shore Hospital, St Leonards, Sydney, NSW, Australia

Introduction: Both obesity and twin gestations recognised risk factors for adverse maternal and neonatal outcomes1, 2. To date, the interaction between obesity and twin pregnancy has been poorly explored. This study aims to examine the impact of obesity on maternal and neonatal outcomes in twin pregnancy.

Methods: Data was collected on singleton and twin gestations within the Northern Sydney Local Health District (2012–2022). Healthy weight was defined as BMI 18.5-24.9kg/m2 and obesity >30kg/m2. Assessment of maternal outcomes included mode of delivery, gestational diabetes mellitus (GDM), and hypertensive disorders, and neonatal outcomes were prematurity, large-for-gestational age (LGA), and neonatal respiratory distress. Multivariate logistic analyses, adjusting for maternal characteristics, were performed.

Results: 33,610 of 50,961 (66%) singletons and 1,060 of 1,632 (65%) twins were born to mothers with healthy weight, and 4,502 (9%) singletons and 192 (12%) twins were born to mothers with obesity. In twin pregnancies with obesity, GDM and LGA incidence was twice as likely compared to healthy-weight twin pregnancies (OR 2.32, 95% CI 1.34-4.03, p<0.005, OR 2.01, 95% CI 1.20-3.38, p<0.01 respectively). There was a 3-fold increased risk of extreme prematurity in twin pregnancies with obesity (<28 weeks, OR 3.34 95% CI 2.23-6.26, p<0.001) compared to healthy-weight twin mothers. Additionally, obesity and twin gestations had an increased risk of neonatal respiratory distress (OR 2.15, CI 1.54-2.99, p<0.001) and a 31-fold increased risk of extreme prematurity (OR 31.03, CI 19.93-48.33, p<0.001), compared to healthy-weight singletons.

Conclusion: In twin gestations, obesity is associated with a significant increase in adverse perinatal outcomes. Mothers with obesity have a significant risk of extremely preterm birth, together with GDM, neonatal respiratory distress and LGA. These findings emphasise the critical impact of maternal weight on twin pregnancies, underscoring the importance of proactive healthcare measures for expectant mothers with obesity to mitigate these risks.

  1. Catalano PM and Koutrouvelis GO. Obesity in Pregnancy: ACOG Practice Bulletin, Number 230. Obstet Gynecol 2021; 137: e128-e144. DOI: 10.1097/AOG.0000000000004395.
  2. Marchi J, Berg M, Dencker A, et al. Risks associated with obesity in pregnancy, for the mother and baby: a systematic review of reviews. Obes Rev 2015; 16: 621-638. 20150528. DOI: 10.1111/obr.12288.