Vertical Transmission of Hepatitis C Virus: Risk Factors and Infantile Prognosis

Objectives: To clarify the incidence and risk factors of the vertical transmission of hepatitis C virus (HCV) and to determine the prognosis of the carrier infants. Methods: At our hospital, 1,941 non‐pathological (non‐HIV carriers) Japanese pregnant women were screened for anti‐HCV antibodies. Sera of the antibody‐positive women were examined by the reverse transcription polymerase chain reaction (RT‐PCR) method, and the positive women and their infants were followed by testing HCV‐related markers. Results: The HCV carrier rate among the pregnant women was 3.5% (68/ 1,941). Four among the 65 infants (6.2%) who were successfully followed for more than 6 months developed the HCV carrier‐state. Of all the risk factors examined, only the elevation (≤ 110 IU/l of maternal serum alanine aminotransferase (ALT) was found to be significant for HCV vertical transmission. Seventy‐five and 50% of the carrier infants manifested chemical hepatitis and seroconverted to an HCV‐RNA‐negative status, respectively, during the follow‐up period. Conclusions: The frequency of HCV vertical transmission was 6.2%. Half of the carrier infants became seronegative for HCV‐RNA. HCV vertical transmission was significantly affected by the maternal serum ALT level prior to delivery.