Oral Presentation International Association of the Diabetes and Pregnancy Study Groups 2022 - Hosted by ADIPS

Is Medical Nutrition Therapy for GDM too Glucocentric? (#28)

Robyn Barnes 1
  1. Bankstown-Lidcombe Hospital, Bankstown, NSW, Australia

Traditional GDM management is an evidence based approach which largely focuses on monitoring and treatment of maternal hyperglycaemia. Medical Nutrition Therapy (MNT) is first line therapy, although evidence on the optimal approach is limited. Other non-glycaemic variables may be confounders in randomised controlled trials investigating dietary interventions for GDM management. These same variable may also contribute to variations in therapeutic and pregnancy outcomes. Pre-pregnancy body mass index (BMI) and excessive maternal weight gain may drive insulin resistance and maternal hyperglycaemia. We conducted several studies investigated the relationship between pre-pregnancy BMI, maternal weight gain, and therapeutic and neonatal outcomes in women with GDM. One study of 3281 singleton GDM pregnancies (1992-2015) (1) women found that excessive gestational weight gain independently increased fasting plasma glucose on the oral glucose tolerance test. Further, continued excessive gestational weight gain during GDM management increased the risk of large for gestational age infants and insulin requirements. A further study (n=1034) involved women receiving a personalised weight targets, with supporting individualised dietary advice from a dietitian (2). Women who exceeded or gained less than their personalised target, had less favourable outcomes compared to those who achieved their target. The study findings suggested that weight management after gestational diabetes diagnosis does not appear to be too late, and provides additional benefits to glucose-lowering treatment. We also conducted a national survey which found that most dietitians delivering MNT for GDM provide precise guidance on carbohydrate intake – focusing on controlling post prandial blood glucose levels (3). Further, although a limited number of dietitians reported provision of maternal weight gain advice and routine weighing over 10 years ago, rates are now increasing (3). However as most weight is gained before GDM presentation, there are opportunities to support healthy eating, and maternal weight gain from earlier in pregnancy. This body of evidence shows that weight management before and during GDM management can improve therapeutic and pregnancy outcomes in addition to benefits achieved by management of maternal hyperglycaemia.

  1. 1. Barnes RA, Wong T, Ross GP, Griffiths MM. Smart CE, Collins CE, MacDonald-Wicks L, Flack JR. Excessive Weight Gain Before and During Gestational Diabetes Mellitus Management: What Is the Impact? Diabetes Care. 2020;43(1):74-81.
  2. 2. Barnes RA, Flack JF, Wong T, Ross GP, Griffiths MM, Stephens M, Kourloufas L, Smart CE, Collins CE, MacDonald-Wicks L. Does weight management after gestational diabetes mellitus diagnosis improve pregnancy outcomes? A multi-ethnic cohort study. Diabet Med. 2021;39(1)e14692.
  3. 3. Barnes RA, Morrison M, Flack JR, Ross GP, Smart CE, Collins CE, MacDonald-Wicks L. Medical nutrition therapy for gestational diabetes mellitus in Australia: What has changed in 10 years and how does current practice compare with best practice? J Hum Nutr Diet. 2022 Apr 5.