Lack of mother‐to‐infant transmission of hepatitis C virus in human immunodeficiency virus–seronegative women: A prospective study with hepatitis C virus RNA testing

The published risk of mother‐to‐infant transmission of hepatitis C virus varies according to the population studied and the tests used. In a prospective study we used the polymerase chain reaction to assess the risk of vertical transmission of hepatitis C virus in an unselected population of women uninfected by human immunodeficiency virus. Hepatitis C virus antibodies were sought with a second‐generation enzyme‐linked immunosorbent assay in 2,367 consecutive pregnant women. Forty‐one were positive, and 17 consented to serological follow‐up of their offspring (n = 18). A second‐generation recombinant immunoblot assay, ALT determination and hepatitis C virus RNA testing were performed on maternal sera obtained during pregnancy and sera from the offspring at birth and thereafter. Five older brothers or sisters were also tested. Hepatitis C virus RNA sequences in serum were amplified with a modified nested polymerase chain reaction procedure with primers from the highly conserved 5′ noncoding region of the hepatitis C virus genome. All the neonates were positive for hepatitis C virus antibodies, with enzyme‐linked immunosorbent assay titers and recombinant immunoblot assay patterns similar to those of their mothers. After birth hepatitis C virus antibodies gradually disappeared within 6 mo. Hepatitis C virus RNA was consistently negative in the 18 children from birth to 24 mo (range = 3 to 24 mo) and in the 5 older children, regardless of the hepatitis C virus polymerase chain reaction status of the mothers (8 of whom were positive). In conclusion, the lack of vertical transmission of hepatitis C virus in this study suggests that unselected and human immunodeficiency virus‐negative women are at low risk of perinatal transmission of hepatitis C virus, even in the presence of active hepatitis C virus replication. (H EPATOLOGY 1993;17:772–777.)