Prevention of gestational diabetes in obese pregnant women; a proof of principle study targeting early pregnancy intervention to women at risk

Obesity in pregnancy increases the risk of gestational diabetes (GDM) and its associated adverse outcomes. National Institute for Healthand Care Excellence (NICE) guidelines recommend that all obese women have an oral glucose tolerance test at 24-28 weeks gestation to detect GDM. However, excessive fetal growth in women with obesity is evident before diagnosis of GDM at 20 weeks gestation and is accompanied by an abnormal metabolome. Targeted intervention in early pregnancy is required to prevent GDM and improve outcomes for obese women in pregnancy.

We have developed a novel GDM prediction tool for early pregnancy. Our hypothesis is that giving the two first-line treatments for GDM – dietary advice and/or metformin – early in pregnancy will prevent gestational diabetes by improving glucose tolerance and metabolic function in at-risk obese pregnant women as identified by our prediction tool.

This study will identify obese women at higher risk of GDM and provide proof of principle of the efficacy of diet and/or metformin in high-risk women by the method of continuous glucose monitoring (CGM) and by evaluation of a targeted metabolome. Our study will determine feasibility of the intervention for obese pregnant women receiving antenatal care from the NHS.