Mothers Pass Hepatitis C More Often to Infant Girls

NEW YORK (Reuters Health) - The results of a large European study suggest that mother-to-child transmission of hepatitis C virus (HCV) occurs significantly more often among girls than among boys.

The study findings, based on 1,787 HCV-infected pregnant women and their infants seen at 33 centers, also "strongly suggest" that women should not be encouraged to undergo elective cesarean section or discouraged from breast feeding solely in the hopes of preventing mother-to-child HCV transmission, the researchers add.

The overall mother-to-child HCV transmission rate for the study group was low (6.2 percent), Dr. Pier-Angelo Tovo from the University of Turin in Italy and colleagues report in The Journal of Infectious Diseases.

According to the team, elective cesarean section did not protect against HCV transmission. Maternal history of injection drug use, prematurity, and breast-feeding were also not significantly associated with mother-to-child HCV transmission. HCV transmission occurred more often in women with detectable levels of virus in their blood, but it also occurred in a few women without detectable virus.

As mentioned, Tovo and colleagues found that girls were twice as likely to be infected with HCV as were boys. To their knowledge, this is the first report of a significant association between sex and HCV vertical transmission.

The sex association is "an intriguing finding" that probably reflects hormonal or genetic differences in susceptibility or response to infection between males and females, they suggest.

In a related editorial, Dr. R. Palmer Beasley from the University of Texas in Houston says the higher HCV infection rates in female infants of HCV-infected mothers is "interesting, provocative, and worth further investigation."

This finding, the author further notes, is in accord with recent observations of similar excesses of HIV infections in infant girls of HIV-infected mothers.

SOURCE: The Journal of Infectious Disease, December 1, 2005.