Correlation of HbA1c levels in pregnancy with maternal and perinatal outcomes at Rahima Moosa Mother and Child Hospital

Abstract

Background: Limited data exists regarding the prognostic value of glycated haemoglobin A1c (HbA1c) levels during pregnancy in relation to perinatal and maternal outcomes. This study investigates the indications for HbA1c testing at Rahima Moosa Mother and Child Hospital (RMMCH), including its correlation with both perinatal and maternal outcomes. Methods: A retrospective analysis of 298 antenatal patient records with HbA1c tests at RMMCH over 3 months (January to March 2020) was conducted. Data were retrieved from the National Health Laboratory Service (NHLS) database and managed using REDCap. Descriptive and analytical statistics were performed using Stata statistical software version 15 (Stata Corp, Texas, USA). Results: The majority of the women were between the age of 18 to 34 (n=199, 66.8%), African ethnicity (n= 215, 72,2%), had multiparity and class I obesity (n=106, 43.1%). The commonest indication for HbA1c testing was body mass index at booking (BMI: n=135, 54.9%) , followed by gestational diabetes mellitus (GDM: n=96, 22.5%) and advanced maternal age (AMA: n=56, 13.1%). A significant relationship was noted between HbA1c ≥6.5% and maternal outcomes such as post-partum haemorrhage (PPH: p-value=0.0004) and diabetic ketoacidosis (p-value=0.0003). In terms of perinatal outcomes, a significant relationship was also noted between HbA1c ≥6.5% and APGAR score at 5 min (p- value=0.0050), birthweight (p-value=0.0500), and macrosomia (p-value=0.0161). Conclusion: The commonest indications for HbA1c testing at the study site were monitoring of GDM, high BMI and AMA. The sensitivity of HbA1c to detect adverse outcome is higher at 6.5%, however a value of >7.0% would achieve higher sensitivity if used for screening for adverse outcomes. HbA1c is associated with maternal and perinatal adverse outcomes making it a useful tool in the management of GDM.