The critical role of late-pregnancy glycemic control for perinatal outcomes: a prospective cohort study
摘要
The impact of late-pregnancy glycemic control on pregnancy outcomes, especially in women with normal oral glucose tolerance test (OGTT) in mid-pregnancy, remain unclear. This study aimed to explore the potential benefits of maintaining glycemic levels within the target range during late pregnancy for improving pregnancy outcomes.
MethodsA prospective cohort study (2018–2022) categorized participants into four groups based on the results of OGTT in mid-pregnancy and late-pregnancy fasting blood glucose (FBG) level: (1) Persistent normoglycemic group (PNG): normal OGTT, FBG < 5.3 mmol/L; (2) Late-pregnancy isolated hyperglycemia group (LPIHG): normal OGTT, FBG ≥ 5.3 mmol/L; (3) Gestational diabetes mellitus (GDM) with target glycemic control group (GDM-TC): GDM diagnosis, FBG < 5.3 mmol/L; (4) GDM with suboptimal glycemic control group (GDM-SC): GDM diagnosis, FBG ≥ 5.3 mmol/L. Associations with adverse perinatal outcomes were assessed using multivariate logistic regressions and population attributable fractions (PAF).
ResultsA total of 35,378 pregnant women were included. The average age and pre-pregnancy BMI of all participants were 32.04 ± 3.85 and 21.86 ± 3.34 kg/m2. Of the participants, 15.43% were diagnosed with GDM. Among those with GDM, 9.27% had elevated FBG (≥ 5.3 mmol/L) in third trimester, whereas 2.01% of participants with a normal OGTT showed high FBG levels in late pregnancy. Compared to PNG, the risk of premature birth was significantly higher in the LPIHG, GDM-TC, and GDM-SC groups, with odds ratios (ORs) of 3.228 (2.503–4.162), 1.267 (1.097–1.463), and 1.883 (1.354–2.619) respectively. More importantly, significantly higher risks of adverse pregnancy outcomes, including cesarean section, macrosomia, and large-for-gestational age (LGA), were found in LPIHG and GDM-SC groups, with ORs of 1.335 (1.130–1.578) and 1.529 (1.272–1.838) for cesarean section; 1.579 (1.200-2.076) and 1.921 (1.474–2.504) for macrosomia; 1.477 (1.165–1.873) and 2.121 (1.699–2.648) for LGA. Given optimal late-pregnancy glycemic control, the respective PAF estimates were 0.8% (cesarean section), 5.0% (premature birth), 1.2% (macrosomia), and 1.1% (LGA) for non-GDM women; and 4.8% (cesarean section), 5.3% (premature birth), 10.0% (macrosomia), 11.0% (LGA), and 9.6% (shoulder dystocia) for GDM women.
ConclusionThis study suggests that the optimal late-pregnancy glycemic control is significantly associated with improved perinatal outcomes, even in women with normal OGTT in second trimester.