Correlation Between HbA1c Levels in Pregnant Women with Gestational Diabetes Mellitus During the Third Trimester and the Blood Glucose Levels and Birth Weight of Late Preterm Infants
LI Xiaoyu
HAO Qingfei
ZHANG Jing
DU Yanna
CHENG Xiuyong
Abstract：Objective To investigate the association between glycated hemoglobin(HbA1c)measured in the third trimester in pregnant women with gestational diabetes mellitus(GDM)and blood glucose and birth weight in late preterm infants.Methods A total of 436 pregnant women with GDM in the First Affiliated Hospital of Zhengzhou University from January 2018 to January 2023 were included in this retrospective cohort study.Cases were stratified into the following groups based on the HbA1c level:Gl group(HbA1c＜5.5％),G2group(5.5％-＜6.0％)and G3 group(HbA1c ≥6.0％).Neonatal birth weight and the lowest blood glucose level within 24 hours after birth were selected as the outcomes.Spearman partial correlation analysis was used to verify the linear relationships between maternal HbA1c in the third trimester and the neonatal blood glucose levels.A multipe linear regression model was used to analyze the association between maternal HbA1c in the third trimester and neonatal birthweight.Multivariate logistic regression analysis model was used to evaluate the relationship between maternal HbA1c in the third trimester and neonatal hypoglycemia and large for gestational age(LGA)in late preterm infants,as well as to adjust for potential confounders.Results The incidence of hypoglycemia and LGA in G3 group was higher than G1 and G2 groups(P＜0.001).Spearman partial correlation analysis showed that HbA1c in the third trimester was negatively correlated with the lowest blood glucose level within 24 hours after birth of late preterm infants(r=-0.136,P=0.015).The result of multipe linear regression model showed that,after adjusting for potential confounding,for every 0.1％increase in maternal HbA1c in the third trimester,the birth weight of the newborn was increased by 22 g(β=22,95％CI:16-28,P＜0.001).When HbA1c was included in the multivariate logistic regression analysis model as continuous variable and categorical variable respectively,after adjusting for potential confounding factors,the results showed that for every 1％increase in HbA1c in the third trimester,the risk of hypoglycemia within 24 hours after birth of late preterm infants increased by 0.786 times(aOR=1.786,95％CI:1.287-2.479,P=0.001),the risk of LGA increased 1.441 times(aOR=2.441,95％CI:1.628-3.660,P＜0.001).Compared with G2 group,there was no significant change in the risk of hypoglycemia in G1 group,but the risk of LGA was significantly decreased.In addition,the risks of hypoglycemia and LGA were both increased in G3 group(P＜0.05).Conclusion The maternal HbA1c of GDM pregnant women in the third trimester is associated with the birth weight and blood glucose of late preterm infants.Strict glycemic control in the third trimester can significantly reduce the incidence of LGA and hypoglycemia in late preterm infants.
Keywords：gestational diabetes mellitusglycated hemoglobinlate preterm infantneonatal hypoglycemialarge for gestational age
Publication Date：2026-02-28
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：6( 602-607 )