Individualized nutritional intervention compared with routine care for gestational diabetes prevention: a randomized controlled trial.

BACKGROUND

Gestational diabetes mellitus (GDM) affects millions of females and their children. Effective dietary strategies for early prevention are controversial.

OBJECTIVES

This study aims to investigate whether an individualized nutritional intervention reduced GDM incidence in high-risk females.

METHODS

A randomized trial was conducted at 3 tertiary hospitals in Shanghai, China. We randomly assigned (1:1) pregnant females in the first trimester who were identified to be at high risk of GDM by a prediction model to either an individualized nutritional intervention or usual care. The intervention consisted of 3 dietary consultations by dietitians based on Chinese dietary guidelines before the oral glucose tolerance test (OGTT) at 24-28 wk of gestation. The control group received usual care. All participants provided 3-d food records at each follow-up. The primary outcome was GDM incidence using the International Association of Diabetes and Pregnancy Study Group criteria. Key secondary outcomes were dietary alterations, gestational weight gain (GWG), maternal metabolic profile, perinatal and pregnancy outcomes. Intention-to-treat analyses were conducted.

RESULTS

A total of 519 females were enrolled, of whom 261 were assigned to the intervention and 258 to usual care. GDM was diagnosed in 85/245 (34.7%) females in the intervention group compared with 89/244 (36.5%) in the control group [adjusted relative risk 0.91 (95% confidence interval: 0.73, 1.15), P = 0.44]. More females in the intervention group had an appropriate GWG than the control group [1.38 (1.06, 1.79)] and lower levels of fasting and 2-h insulin during the OGTT (P < 0.001). We observed a reduction in the rate of small for gestational age in the intervention group compared with the control group [0.11 (0.01, 0.80)] and neonatal hypoglycemia [0.14 (0.04, 0.57)].

CONCLUSIONS

Among females at risk of GDM, an individualized nutritional intervention based on Chinese dietary guidelines provided before the OGTT did not prevent GDM but helped to manage GWG appropriately and improved pregnancy outcomes. This trial was registered on 27 October, 2019, with initial participant enrollment on 5 May, 2020 at ChiCTR as 1900026963 (https://www.chictr.org.cn/searchproj.html?regno=1900026963).