Incidence, determinants and outcomes of pregnancy-associated hepatitis B flares: A regional hospital-based cohort study

Background & Aims: There is limited knowledge about hepatitis B virus (HBV) flare among pregnant women. We evaluated the incidence, determinants and outcomes of HBV flare in a multicultural cohort of pregnant HBV-infected women in the United States. Methods: We performed a retrospective cohort study of pregnant hepatitis B surface antigen-positive women cared for at hospital-based clinics of 4 medical centres in Southeastern Pennsylvania from 2006 to 2015. The main outcome was incident HBV flare (alanine aminotransferase [ALT] ≥2 times upper limit of normal) during pregnancy or within 6 months after delivery. Among patients with flare, we determined development of jaundice (total bilirubin ≥2.5 mg/dL) and hepatic decompensation. Multivariable logistic regression was used to estimate odds ratios (ORs) of HBV flare for risk factors of interest, including timing of flare (during pregnancy versus post-delivery), nulliparity, younger age, HBV e antigen (HBeAg) status, and lack of anti-HBV therapy. Results: Among 310 pregnant predominantly African HBV-infected women with 388 pregnancies, the incidence of HBV flare was 14% (95% CI, 10-18%) during pregnancy and 16% (95% CI, 11-24%) post-delivery. Jaundice developed in 12% and hepatic decompensation in 2%. Positive HBeAg was associated with HBV flare (OR, 2.55; 95% CI, 1.04-6.20). HBV DNA was measured in 55% of patients, and only 50% were referred for HBV specialty care. Conclusions: Pregnancy-associated hepatitis B flare occurred in 14% during pregnancy and 16% post-delivery and rarely led to hepatic decompensation. Positive HBeAg was the main risk factor identified. Women did not have adequate HBV monitoring or follow-up during pregnancy.