LAUSR

To the Editor: Gestational diabetes mellitus (GDM) affected approximately 12.8% of pregnancies worldwide in 2019 according to the estimation of the International Diabetes Federation [1]. Growing evidence suggests that women with a history of GDM have a markedly increased risk of diabetes later in life [2], but it is still unknown whether intensive management of GDM has benefits for prevention of maternal diabetes at postpartum and later in life. Our group conducted a population-based RCT testing the effectiveness of intensive lifestyle intervention of GDM on the risk of macrosomia and large-for-gestational-age (LGA) in the three-tier antenatal care network of Tianjin, China.We found that such an intervention reduced the risk of macrosomia and LGA in offspring of women with GDM [3]. In the current analysis, we investigate the effect of lifestyle intervention on maternal postpartum diabetes among women with prior GDM. Details of the study setting, design and participants are reported elsewhere [3]. Briefly, 19,847 pregnant women were enrolled and offered a 50 g 1 h glucose challenge test (GCT) between the 24th and 28th week of gestation, at primary hospitals.Women who had GCT ≥7.8 mmol/l (n = 2921) were referred to the Tianjin Women and Children’s Health Center (Tianjin, China) to undergo a 75 g 2 h OGTT. Based on the International Association of Diabetes and Pregnancy Study Group’s criteria, GDM was diagnosed as: fasting plasma glucose (PG) ≥5.1 mmol/l; 1 h PG ≥10.0 mmol/l; or 2 h PG ≥8.5 mmol/l. Of the 2921 participants, 1440 pregnant women were diagnosed with GDM. In the previous analysis [3], 734 women were sequentially excluded due to not being invited to participate in the late stage of the fieldwork (n = 52), meeting one or more of exclusion criteria (n = 440) or receiving unintentional intervention (n = 242). Ultimately, 706 women received either intensive care (n = 344) or usual care (n = 362). The intensive care intervention included three individualised advice sessions on diet and physical activity and three group education sessions. The details of the intensive care intervention have been published previously [3]. Ninghua Li and Jinnan Liu contributed equally to this study.