<p>A health facility-based quantitative cross-sectional study was conducted among pregnant women LWHIV attending PMTCT in selected health facilities in Mtwara region. A structured questionnaire was used to collect socio-demographic characteristics, clinical, socio-cultural and laboratory information (including syphilis, HIV viral load and CD4 count results tested within 6 months). Blood specimens were screened for HBV and confirmed using rapid diagnostic tests and automated ELISA test (Abbot ARCHITECT-PLUS®i2000SR immunoassay analyzer,U.S.A.) respectively. Variables with p&lt;0.05 were considered significantly associated with HBV infection in pregnant women LWHIV.</p>