The predictive ability of the triglyceride glucose index, fasting glucose and oral glucose tolerance test for postpartum hyperglycemia in women with a GDM history.

Objective: This study aimed to determine the likelihood of hyperglycemia postpartum in women with gestational diabetes mellitus (GDM) and to identify the predictors.

Methods: The retrospective cohort study involved 1 527 GDM patients who delivered at Peking University First Hospital from 1 January 2021, to 31 December 2021. According to the blood glucose level of postpartum oral glucose tolerance test (OGTT), women were divided into a normal glucose tolerance (NGT) group and a hyperglycemia group, and their characteristics and risk factors of hyperglycemia were compared.

Results: The prevalence of hyperglycemia was 33.9% (184/543) at 6-12 weeks postpartum. Compared with the NGT group, the fasting plasma glucose (FPG) of hyperglycemia group increased significantly during pregnancy and postpartum, the OGTT 1h postprandial glucose (PG) and 2hPG increased in the second trimester of pregnancy, the triglyceride (TG) increased in the first trimester of pregnancy and postpartum, the triglyceride glucose (TyG) index increased in the first trimester of pregnancy and postpartum, and the total cholesterol (TCHO) and low density lipoprotein cholesterol (LDL-C) decreased in the second trimester (p < 0.05). Fasting plasma glucose (FPG) in the first trimester [odds ratio (OR) = 3.583, p < 0.001], OGTT 2hPG in the second trimester (OR = 1.604, p < 0.001), the TyG index in the first trimester (OR = 1.863, p = 0.045) and FPG in third trimester (OR = 1.985, p = 0.024) were independent risk factors for postpartum hyperglycemia.

Conclusions: Approximately one-third of women with GDM have hyperglycemia 6-12 weeks after delivery. FPG and the TyG index in the first trimester, OGTT 2hPG in the second trimester and FPG in third trimester are risk factors for postpartum hyperglycemia.