Moutchia J, Njouom R, Rumpler E, et al. - Researchers herein investigated the correlation between median maternal age at first childbirth in a preceding generation, a proxy for the frequency of mother-to-child transmission (MTCT) of HBV in a region, and the risk of chronic HBV infection, defined as positive surface antigen (HBsAg), in the index generation by assessing a nationally representative population-based sample from all 58 administrative divisions in Cameroon. Historical data from Demographic Health Surveys (DHS) in 1991/1998/2004/2011 were used to estimate a division-specific median maternal age at first childbirth. HBsAg was tested in 2011 DHS participants. The overall weighted prevalence of HBsAg of 11.9% was recorded among 14,150 participants (median 27 years old, 51% females), with a wide geographical variation across the divisions (range: 6.3-23.7%). Findings revealed a significant correlation between the maternal age at first childbirth and HBsAg-positivity; lower maternal age at first childbirth was significantly linked with positive HBsAg at the division level, and at the individual level. This suggests that in some areas in Cameroon, MTCT plays a crucial role in maintaining high HBV endemicity. This highlights an urgent necessity for effectively preventing MTCT in order to achieve WHO’s global hepatitis elimination goals.