Background: Hepatitis B virus (HBV) is the main cause of serious liver infection. Factors that increase the risk of HBV infection include contact during child birth and different horizontal means of transmission, such as unprotected sexual exposure with an infected person and having direct contact with the blood of an infected person.

Objectives: The main aim of this study is to determine seroprevalence of HBV infection and associated risk factors among mothers in Gondar, Northwest Ethiopia.

Methods: A community based cross-sectional study was conducted on mothers in Gondar from March to November 2016. Study participants were selected using a multistage cluster random sampling technique and a total of 419 mothers were included. Sociodemographic data and exposure to associated factors (hospital admission, history of circumcision, history of contact with jaundiced family and history of abortion) were collected through a structured questionnaire. Five milliliters of blood were collected from each study participant. Serum level hepatitis B surface antigen (HBsAg) and anti-HBc were detected using sandwich and indirect ELISA, respectively. The data were entered with Epi Info 7 and analyzed using SPSS version 20. To declare the presence of association, odds ratio with 95% confidence interval and p-value< 0.05 were considered statistically significant. Result: A total of 419 mothers with the median age of 29 (20-58) years old were enrolled. The sero-prevalence of HBsAg and anti-HBc was 3.8% and 36.0%, respectively. Statistically significant association with HBV infection was observed for age (AOR= 6.960, 96% CI, 2.047-23.659, P= 0.002), history of hospital admission (AOR= 3.279, 95% CI, 1.054-10.195, P= 0.04), history of circumcision (AOR= 4.394, 95% CI, 1.463-13.198, P= 0.008), history of contact with jaundiced family (AOR= 3.877, 95% CI, 1.274-11.795, P= 0.017) and history of abortion (AOR= 4.867, 95% CI, 1.438-16.473, P= 0.011).

Conclusions and recommendations: An intermediate seroprevalence of HBV infection, which is an important public health problem in the area, was detected. Therefore, implementing strategies for routine screening and care of mothers for hepatitis B virus would be important. Further, health education on modes of transmission and precautions and immunization of HBV has to be strengthened.