Hepatitis B Viral Load Patterns in HBsAg-Positive Antenatal Women and their Correlation with Stages of Pregnancy: A Cross-sectional Study

Introduction: Screening for Hepatitis B Surface Antigen (HBsAg) during pregnancy is essential, as maternal viremia is directly proportional to perinatal transmission. However, there is insufficient literature available on the viral load pattern of Hepatitis B Virus (HBV) in different trimesters of pregnancy. Aim: The aim of this study was to investigate the seroprevalence and estimate the viral load of HBsAg among antenatal women in different trimesters of pregnancy. Materials and Methods: A hospital-based cross-sectional study was conducted in the Department of Microbiology at Jorhat Medical College and Hospital in Jorhat, Assam, India, from June 2017 to May 2018. A total of 7833 samples were collected from antenatal cases attending the Outpatient Department of Obstetrics and Gynaecology. HBsAg positive cases were screened using a rapid diagnostic kit and Enzymelinked Immunosorbent Assay (ELISA). Viral load was estimated using Reverse Transcription Polymerase Chain Reaction (RTPCR) after obtaining written consent. Positive patients were followed up, and viral load estimation was repeated in each trimester. Statistical analysis was performed using Epi Info software and the Mann-Whitney U test. Results: The mean age of the HBsAg positive antenatal women who participated in the study was 25.97±3.72 years. Out of the 7833 patients screened, 32 antenatal patients were found to be positive for HBsAg. The highest viral load was found to be 1 log10 (25%) and 6 log10 (25%) IU/mL. The median viral load was highest in the second trimester at 1.434×106 IU/mL, followed by the third trimester at 7.003×105 IU/mL, and the first trimester at 43.6482 IU/mL. Conclusion: The pattern of HBV viral load indicates that patients in the first trimester either had borderline or low levels compared to those in the second and third trimesters. Since the viral load pattern varies in different trimesters of pregnancy, viral load estimation is crucial for the treatment of positive patients and to reduce HBV vertical transmissions.