Proportion of HBV-infected pregnant women eligible for antiviral prophylaxis to prevent vertical transmission: a systematic review and meta-analysis

Background & Aims In 2020, WHO recommended peripartum antiviral prophylaxis (PAP) for HBV-infected pregnant women with high viremia (≥200,000 IU/mL). Hepatitis B e antigen (HBeAg) was also recommended as an alternative where HBV DNA is unavailable. To inform policy-making and implementation of prevention of mother-to-child transmission, we conducted a systematic review and meta-analysis to estimate proportion of HBV-infected pregnant women eligible for PAP at global and regional levels. Methods We searched PubMed/EMBASE/Scopus/CENTRAL for studies of HBV-infected pregnant women. We extracted proportions of women with high viremia (≥200,000 IU/mL), positive HBeAg, cross-stratified proportions based on HBV DNA and HBeAg, and the child infection risk. Proportions were pooled using random-effects meta-analysis. Results Of 6,999 articles, 131 studies involving 71,712 HBV-infected pregnant women were included. The number of studies per WHO region was 66 (Western Pacific), 21 (Europe), 17 (Africa), 11 (Americas), 9 (Eastern Mediterranean), and 7 (South-East Asia). The overall pooled proportion of high viremia was 21.27% (95% CI 17.77-25.23), with significant regional variation: Western Pacific (31.56%), Americas (23.06%), South-East Asia (15.62%), Africa (12.45%), Europe (9.98%) and Eastern Mediterranean (7.81%). HBeAg positivity showed similar regional variation. After cross-stratification, the proportions of high viremia and positive HBeAg, high viremia and negative HBeAg, low viremia and positive HBeAg, and low viremia and negative HBeAg were 14.80% (10.75-20.05), 2.62% (1.81-3.78), 3.66% (2.83-4.73), and 76.18% (69.79-81.58%), respectively. The corresponding risks of child infection following birth dose vaccination without immune globulin and PAP were 14.86% (8.43-24.88), 6.94% (2.92-15.62), 7.14% (1.00-37.03), and 0.14% (0.02-1.00). Conclusions Approximately 20% of HBV-infected pregnant are eligible for PAP. Given significant regional variations, each country should tailor strategies for HBsAg screening, risk stratification, and PAP in routine antenatal care. Impact and implications In 2020, the WHO recommended that pregnant women who test positive for the hepatitis B surface antigen (HBsAg) undergo HBV DNA testing or hepatitis B e antigen (HBeAg), and those with high viremia (≥200,000 IU/mL) or positive HBeAg receive peripartum antiviral prophylaxis (PAP). To effectively implement new HBV PMTCT interventions and integrate HBV screening, risk stratification, and antiviral prophylaxis into routine antenatal care services, estimating the proportion of HBV-infected pregnant women eligible for PAP is critical. In this systematic review and meta-analysis, we found that approximately one-fifth of HBV-infected pregnant women are eligible for PAP based on HBV DNA testing, and a similar proportion is eligible based on HBeAg testing. Due to substantial regional variations in eligibility proportions and the availability and costs of different tests, it is vital for each country to optimize strategies that integrate HBV screening, risk stratification, and PAP into routine antenatal care services.