RESUMEN
This study was a meta-analysis of the literature on the efficacy and safety of tenofovir disoproxil fumarate (TDF) in preventing vertical transmission of hepatitis B in pregnancies with high viral load. Four observational studies and one randomized controlled trial involving 585 pregnant women and 595 newborns were included in the meta-analysis. TDF was more effective than the placebo in reducing vertical transmission in HBeAg-positive chronic hepatitis B (CHB) pregnancies with high serum HBV-DNA levels (OR = 0.21, 95% CI = 0.07-0.61) at 4-12 months, infant HBV DNA seropositivity at delivery (OR = 0.16, 95% CI = 0.07-0.37), and a severe flair in maternal alanine aminotransferase (ALT) levels (OR = 0.43, 95% CI = 0.19-0.95) during pregnancy. In addition, TDF showed more improvement in HBV DNA suppression at delivery (OR = 254.46, 95% CI = 28.39-2280.79). No significant differences were found in HBeAg seroconversion or ALT normalization; or in rates of cesarean section, emergent cesarean section, postpartum hemorrhage, prematurity, congenital malformations, or infant death. However, TDF induced more drug-related adverse events (OR = 2.33, 95% CI = 1.39-3.89) and elevated creatine kinase (CK) (OR = 9.56, 95% CI = 1.17-78.09) than in controls. The available evidence suggests that TDF is effective and safe in preventing vertical transmission of hepatitis B in pregnancies exhibiting a high viral load.