To further reduce mother-to-child transmission (MTCT), this study aims to explore the factors influencing MTCT rate in pregnant women with extremely high HBV DNA loads (HBV DNA ≥ 1 × 107 IU/ml). In this retrospective real-world study, pregnant women with chronic hepatitis B virus (HBV) infection and their infants were analyzed. Pregnant women received antiviral therapy during the second or third trimester based on their HBV DNA loads and personal preferences. Newborns were administered hepatitis B immunoglobulin (HBIG) and hepatitis B vaccine within 6 h after birth, while their HBV infection status was followed up after 7 months. Data from 4,157 pregnant women and 4192 infants were collected. All 35 cases of MTCT occurred in mothers with extremely high HBV DNA loads (1570 mothers and 1588 infants), of which 29 cases were in nonantiviral therapy group, and 6 in antiviral therapy group. Antiviral treatment could markedly reduce MTCT rate (p 5 IU/ml or above didn't impact MTCT rate after antiviral treatment. The average initiating antiviral treatment time among mothers with MTCT was significantly later than mothers without MTCT (p = 0.008). In the absence of antiviral treatment, predelivery HBV DNA levels in mothers with MTCT were higher compared to those without MTCT (p = 0.001). MTCT mainly occurred in pregnant women with extremely high HBV DNA loads; however, antiviral treatment could reduce MTCT rate. The efficacy of antiviral drugs did not affect the incidence of MTCT, but early initiation of antiviral treatment may contribute to a decrease in its occurrence.
Yi et al. (Sun,) studied this question.