Anti-viral therapy for prevention of perinatal HBV transmission: extending therapy beyond birth does not protect against post-partum flare.

ABSTRACT

BACKGROUND: Antepartum anti-viral therapy (AVT) is often administered to prevent perinatal transmission of hepatitis B virus (HBV) infection. Little is known about the effect of AVT on post-partum flare rates and severity. AIM: To examine whether extending AVT beyond birth influences the post-partum course. METHODS: One hundred and one pregnancies in 91 women with HBV DNA levels ≥log 7 IU/mL were included. AVT (initially lamivudine, later tenofovir disoproxil fumarate) was commenced from 32 weeks gestation and stopped soon after birth and at 12 weeks post-partum. Outcomes according to post-partum treatment duration were examined Group 1 = AVT ≤4 weeks (n = 44), Group 2 = AVT >4 weeks (n = 43), Group 3 = no AVT (n = 14). RESULTS: The majority of women were HBeAg+ (97%), median age 29 years, baseline HBV DNA log 8.0 IU/mL and follow-up 48 weeks post-partum. Post-partum treatment duration was 2 weeks for Group 1 and 12 weeks for Group 2, P < 0.01. Flare rates were not significantly different Group 1 = 22/44 (50%), Group 2 = 17/43 (40%) and Group 3 = 4/14 (29%), P = 0.32. Onset of flare was similar at 8/10/9 weeks post-partum for Groups 1/2/3 respectively, P = 0.34. The majority of flares spontaneously resolved. HBeAg seroconversion (n = 1/5/1 in Groups 1/2/3, P = 0.27) was not associated with treatment duration or the occurrence of a post-partum flare. CONCLUSIONS: Post-partum flares are common and usually arise early after delivery. They are often mild in severity and most spontaneously resolve. Extending anti-viral therapy does not protect against post-partum flares or affect HBeAg seroconversion rates.