Aim: To investigate the frequency and timing of post-partum chronic hepatitis B virus (HBV) reactivation and identify its pre-partum predictors.
Methods: Forty-one hepatitis B e antigen (HBeAg)-negative chronic HBV infected pregnant women were prospectively evaluated between the 28th and the 32nd week of gestation. Subjects were re-evaluated at 3-mo intervals during the first post-partum year and every 6 mo during the following years. HBV DNA was determined using real-time reverse transcription polymerase chain reaction (Cobas TaqMan HBV Test) with a lower detection limit of 8 IU/mL. Post-partum reactivation (PPR) was defined as abnormal alanine aminotransaminase (ALT) levels and HBV DNA above 2000 IU/mL.
Results: Fourteen out of 41 women (34.1%) had pre-partum HBV DNA levels>2000 IU/mL, 18 (43.9%) had levels<2000 IU/mL and 9 (21.9%) had undetectable levels. Fourteen women were lost to follow-up (failure to return). PPR occurred in 8 of the 27 (29.6%) women evaluated, all within the first 6 mo after delivery (5 at month 3; 3 at month 6). Five of the 6 (83.3%) women with pre-partum HBV DNA>10000 IU/mL exhibited PPR compared with 3 of the 21 (14.3%) women with HBV DNA<10000 IU/mL (two with HBV DNA>2000 and the third with HBV DNA of 1850 IU/mL), P=0.004. An HBV DNA level≥10000 IU/mL independently predicted post-partum HBV infection reactivation (OR=57.02, P=0.033). Mean pre-partum ALT levels presented a non-significant increase in PPR cases (47.3 IU/L vs 22.2 IU/L, respectively, P=0.094).
Conclusion: In the present study, PPR occurred in approximately 30% of HBeAg-negative pregnant women; all events were observed during the first semester after delivery. Pre-partum HBV DNA level>10000 IU/mL predicted PPR.
Keywords: Hepatitis B; Hepatitis B virus-DNA; Post-Partum; Pregnancy; Reactivation.