Poster Presentation Australian & New Zealand Obesity Society 2016 Annual Scientific Meeting

Pilot Study: The impact of substantial pre-conception weight loss in obese women on glucose control at 26-28 weeks of pregnancy (#264)

Sarah Price 1 , Priya Sumithran 1 , Alison Nankervis 2 3 , Michael Permezel 4 , Jeffrey Craig 5 , Luke Prendergast 6 , Joseph Proietto 1
  1. Department of Medicine, University of Melbourne, Heidelberg, VIC, Australia
  2. Department of Diabetes and Endocrinology, Royal Melbourne Hospital, Melbourne, Victoria, Australia
  3. Royal Women’s Hospital, Melbourne, Victoria, Australia
  4. Department of Obstetrics and Gynaecology, University of Melbourne, Heidelberg, VIC, Australia
  5. Early Life Epigenetics, Murdoch Childrens Research Institute, Flemington, VIC, Australia
  6. Department of Mathematics and Statistics, LaTrobe University, Bundoora, VIC, Australia

Background: In Australia, 1 in 3 women of reproductive age are obese, but no pre-pregnancy weight loss interventions have been shown to reduce the risk of obesity-related pregnancy complications for both mother and child. The HAPO study (NEJM 2008;358:1991-2002) observed that small changes in maternal glucose at 26-28 weeks gestation are associated with significant changes in the rate of adverse pregnancy outcomes.

Aim: To determine if substantial pre-conception weight loss (10-15% body weight) in obese (BMI>30kg/m2) women reduces fasting glucose at 26-28 weeks gestation by ≥10% compared with modest (≤3%) weight loss.

Method: 78 women were randomised to either a lifestyle program expecting modest weight loss (MWL; ≤3% body weight; n=38), or a modified VLED program expecting substantial weight loss (SWL; 10-15% body weight; n=40). Attrition over the 12-week program was 20% (MWL 10/38 (25%), SWL 6/40 (15%)). Only completers were considered in the preliminary analysis. Subjects were followed for 12 months and if pregnancy occurred, maternal plasma glucose was measured at 26-28 weeks gestation. Of the 24 subjects who were >6 months post-intervention, 10 were pregnant and had completed 28 weeks gestation.

Results: Weight loss in the MWL (n=28) and SWL (n=34) groups was 2.1% and 13.1% respectively. Mean reduction in plasma glucose after 12 weeks was 1.24% (SE 1.40) in MWL and 9.12% (SE 1.83) in SWL group. Of those who achieved pregnancy (MWL= 3, SWL=7), mean decrease in plasma glucose between the start of the weight loss program and 26-28 week gestation was 1.85% (SE 1.83) and 11.51% (SE 3.17) in the MWL and SWL groups respectively. 

Conclusion: This pilot data suggests that, in obese women, pre-conception weight loss results in a decrease in fasting plasma glucose which is maintained into pregnancy. The reduction in plasma glucose is greater when substantial pre-pregnancy weight loss is achieved.