CESAREAN-SECTION AND RISK OF VERTICAL TRANSMISSION OF HIV-1 INFECTION

Indirect evidence suggests that a significant proportion of vertical t ransmission of HIV infection occurs late in pregnancy or during delive ry. Caesarean section, therefore, may protect the fetus from infection . We looked at 1254 HIV-infected mothers and their children and the ef fects of different modes of delivery on transmission risk. We also inc luded a detailed assessment of confounding factors associated with tra nsmission risk. Women who had caesarean sections were more advanced in their disease progression which may cause the protective effect of ca esarean section to be underestimated. When this and other potential co nfounding factors were taken into account, caesarean section was estim ated to halve the rate of transmission. This finding is important in t he design of studies to evaluate treatments aimed at reducing mother-t o-child transmission.