Opportunities for Prevention of Gestational Diabetes Before 24 Weeks of Gestation

Gestational diabetes (GDM), increasingly prevalent worldwide, is related to growing pregnancy complications and long-term metabolic risks for the woman and the descendants. The aim of this study is to determine the optimal BMI ranges specific for age group and optimal gestational weight gain (GWG) at 24 weeks specific for different pre-BMI (pre-pregnancy body mass index) groups to avoid or reduce the incidence of GDM.

A retrospective cohort study of 3104 pregnant women was conducted in Song Jiang district, Shanghai, China. A multivariate logistic regression analysis was performed with the purpose of determining the OR (odds ratio) of risk factors of GDM including GWG of 24 weeks, pre-BMI, advanced age, and first-degree relatives with DM. Optimal ranges of GWG or pre-BMI are defined as the interval corresponding to lowest or relative lower incidence of GDM.

ORs of pre-BMI, maternal age, GWG at 24 weeks, and first-degree relatives with DM were 1.250, 1.096, 1.142, and 2,098 separately. It is suggested for lowering the incidence of GDM that, to the utmost extent, 12 kg, 9 kg, and 8 kg for GWG at 24 weeks should be the ideal boundary for those pregnant women whose BMI was 15-21 kg/m², 21-23 kg/m², and 23-25 kg/m² respectively. Pre-BMI ≤22 kg/m² would be recommended for an expectant mother whose age is no more than 28 years old. Similarly, women whose age was above 28 years old would be advised to control their BMI below 20 kg/m².

Optimal GWG during pregnancy varies largely by diverse pre-BMI, and likewise, optimal pre-BMI varies a lot by different age group. Public health awareness should be promoted on the importance of having healthy pre-BMI, and achieving optimal weight gain during pregnancy to avoid or reduce the incidence of GDM, especially for those with first-degree relatives with DM.