91 - An individualised nutritional intervention versus usual care for gestational diabetes mellitus prevention in high-risk women

Gestational diabetes mellitus (GDM) is associated with adverse outcomes for pregnant women and their offspring. We investigated whether an individualised nutritional intervention reduces the incidence of GDM in high-risk women.

Study Design:

A randomised controlled trial was conducted at three hospitals in Shanghai, China. We studied pregnant women in the first trimester who were considered to be at high risk of GDM by a prediction model. Participants were randomly assigned (1:1) to either an intervention or usual care. The intervention consisted of three dietary consultations offered monthly by dieticians based on 3-day food records before the oral glucose tolerance test (OGTT) at 24-28 gestational weeks. The control group received usual care and completed food records within the same period. The primary outcome was GDM incidence using the IADPSG criteria. Key secondary outcomes were gestational weight gain (GWG), metabolic profile, perinatal and pregnancy outcomes. Analyses were by modified intention-to-treat.

Results:

Between May 5, 2020 and July 1, 2021, 7082 pregnant women underwent screening, of whom 1666 were eligible. Of the 519 women who provided informed consent, 261 were randomly assigned to the intervention and 258 to usual care. 245 women in the intervention group and 244 in the control group had completed OGTT as per protocol. GDM was diagnosed in 85 (34.7%) women in the intervention group and 89 (36.5%) in the control group [adjusted relative risk 0.91,95% CI 0.73-1.15;p=0.44]. More women in the intervention group had an appropriate rate of GWG (38.3% versus 27.8%, p=0.017), lower levels of insulin at OGTT and improved HOMA2-IR (p < .0001). There was a reduction in the incidence of caesarean section (48.1% vs 60.5%, p=0.006), small for gestational age (0.4% vs 4.0%, p=0.029), neonatal hypoglycaemia (0.8% vs 5.2%, p=0.006) in the intervention group. Maternal dietary quality was also improved in the intervention group.

Conclusion:

In women at high risk for GDM selected by a prediction model, an individualized nutritional intervention delivered before OGTT does not prevent the disease.