Hepatitis B virus infection during pregnancy and the risk of postpartum hemorrhage: a protocol for systematic review and meta-analysis

Hepatitis B virus (HBV) infection is a significant public health issue worldwide, with a hepatitis B surface antigen (HBsAg) seroprevalence of 3.5%. Maternal HBV infection during pregnancy, a common comorbidity, is associated with an increase in the risk of adverse obstetric and perinatal outcomes. However, the relationship between maternal HBV infection and postpartum hemorrhage (PPH), a leading contributor to maternal morbidity and mortality, is currently uncertain. The aim of this study is to comprehensively clarify the potential impact of maternal HBV on PPH risk. The authors initially searched five English databases and three Chinese databases from their inception to 26th June 2023. Two reviewers will independently conduct study selection, data extraction, and quality assessment. Cohort and case–control studies investigating the effect of maternal HBV infection on PPH will be included, with study quality assessed using the Newcastle–Ottawa Scale (NOS). Meta-analyses will be performed using a fixed-effects model for I 2≤50% or a random-effects model otherwise. Several categories of subgroup analyses (e.g. sample size more than 1000 vs. less than 1000) and sensitivity analyses (e.g. omit NOS scores less than 7) will be conducted, and publication bias will be assessed through funnel plots, Begg’s and Egger’s tests using STATA 18.0. This systematic review and meta-analysis do not require ethics approval and the results will be published in peer-reviewed journals. The findings of this systematic review will provide evidence on the impact of maternal HBV infection on PPH, which will contribute to better prevention and management of PPH in clinical practice and a better understanding of the disease burden of HBV infection. CRD42023442626