Increased
rubella susceptibility has been shown in subjects from the Asian-Pacific region where
chronic hepatitis B virus (HBV)
infection is endemic. This study was performed to explore the relationship between chronic HBV
infection and
rubella susceptibility in the obstetric population. We conducted a retrospective cohort study on 50556 pregnant women delivered in a university obstetric unit from January 1998 to June 2008. The incidence of
rubella susceptibility according to maternal HBV carrier status was examined. HBV
infection and
rubella susceptibility were found in 5105 (10.1%) and 6102 (12.1%) women, respectively.
Rubella susceptibility was more common in women with HBV (13.1%vs 12.0%, P = 0.017), even after adjusting for other confounding factors (odds ratio 1.11, 95% confidence interval 1.01-1.21). Advancing age was associated with progressively decreasing odds of
rubella susceptibility, from 0.48 at age 20-24 years to 0.34 at age ≥ 40 years in women without HBV
infection, but had no effect in women with
hepatitis B. In conclusion, our study is the first to demonstrate an association between chronic HBV
infection with
rubella susceptibility. Further studies are warranted to confirm whether chronic HBV
infection, especially that acquired by vertical transmission, may impair the immune response to
rubella vaccine or natural
infection throughout the reproductive age.