Retrospective Evaluation of the Relationship Between Glycated Hemoglobin Levels and Infant Birth Weight in Pregnant Women Diagnosed with Gestational Diabetes Mellitus

Abstract

Objective: Gestational diabetes mellitus (GDM) is any level of glucose intolerance disorder that begins or is recognized during pregnancy for the first time. Glycated hemoglobin (HbA1c) is used in DM diagnosis, treatment, and follow-up. However, there is insufficient data to make a comparable interpretation for HbA1c in pregnant women with GDM. This study aimed to investigate the differences in HbA1c levels and newborn birth weights between GDM and healthy pregnant women.

Methods: A total of 391 pregnant women were enrolled in this study. Of these, 192 were diagnosed with GDM based on the oral glucose tolerance test. Additionally, 199 healthy pregnant women with normal glucose levels were monitored as the control group. Outpatient records of patients were retrospectively scanned.

Results: A total of 192 pregnant women with GDM and 199 healthy normoglycemic pregnant women were included in the study. Among all the pregnant women, 320 (81.8%) gave birth via cesarean section (C/S), while 71 (18.2%) had a normal spontaneous vaginal birth. The frequency of C/S was found to be higher in patients diagnosed with GDM (P < .001). The mean birth weight of all newborns was calculated as 3127.84 ± 674.17 g. The mean birth weight of infants of mothers with GDM was greater than that of infants of healthy pregnancies (P < .001). Newborns with complications in GDM pregnancies had lower birth weights than newborns without complications (P < .001). Complications were discovered in 59 (30.7%) of the pregnant women with GDM. Preterm births in GDM pregnancies were found to be statistically significantly lower when compared to normal pregnancies (P = .01). No significant correlation was found between the birth weight of newborns and maternal HbA1c (P > .05).

Conclusion: No direct effect of HbA1c levels was found on the birth weight of newborns or the development of complications in pregnant women with GDM. These findings indicate a need for further research with larger sample sizes of pregnant women.

Cite this article as: Dumanlı GY, Tabak Ö, Kumbasar A, Aldıkaçtıoğlu Talmaç M. Retrospective evaluation of the relationship between glycated hemoglobin levels and infant birth weight in pregnant women diagnosed with gestational diabetes mellitus. Cerrahpaşa Med J. 2026, 50, 0099, doi: 10.5152/cjm.2026.25099.