Establishing Reference Intervals for HBA1C in All Three Trimesters of Pregnancy; A Cross-Sectional Study on Healthy Pregnant Women of Quetta, Baluchistan

Objective: To establish the reference intervals in healthy pregnant females of Quetta, Baluchistan, for Glycosylated Hemoglobin (HbA1c) in all three trimesters of pregnancy. Study Design: Cross-sectional study. Place and Duration of Study: Pathology Department Combined Military Hospital, Quetta Pakistan, from Jun 2018 to Jun 2019. Methodology: Blood samples of healthy pregnant females were drawn for Glycosylated haemoglobin (HbA1c). Fasting plasma glucose and haemoglobin were also measured to rule out hyperglycemia and anaemia. Samples for Glycated haemoglobin(HbA1c) were analyzed by Turbidimetric Immuno-inhibition (TINIA) method. For all the trimesters, 5th and 95th percentiles were taken as reference intervals for Glycosylated haemoglobin (HbA1c) and compared for each trimester. Results: A total of 388 samples were taken, of which 136(35.05%) females were from the first trimester, 128(32.98%) and 124(31.97%) from the second and third trimesters, respectively. The mean age of the study population was 25.1±3.7 years in the first trimester, 26.7±4.5 years in the second-trimester while and the third trimester it was 26.8±4.8 years. In the first, second,and third trimesters, the reference intervals for Glycosylated haemoglobin (HbA1c) were 3.8-5.2%, 4.1-5.4%, and 4.2-5.7%,respectively. Conclusion: For the exact diagnosis of hyperglycemia in pregnancy, each laboratory should establish its reference intervals of Glycated haemoglobin (HbA1c) for each trimester as it varies from trimester to trimester.