“…Secondly, births delivered born prior to 28 weeks of gestation were not examined in the study, which may leads to a potential underestimation of the overall birth prevalence of congenital malformations, particularly for severe cases that may result in pregnancy termination before 28 gestational weeks. 71 , 72 , 73 As a result, our analysis may underestimate the true associations between maternal HBV infection and risk of congenital malformations in offspring. The magnitude of this underestimation likely differs for different systems of malformations.…”