[Mother-to-child transmission of HIV].

Background: Modern treatment of HIV-positive women has reduced the rate of transmission of HIV to their children. The relative importance of different interventions is unclear. We have studied mother-to-child transmission from the start of the Norwegian epidemic in 1983 and up to the year 2000.

Material And Methods: Retrospective study of risk factors in HIV-positive women and children of HIV-positive mothers born in Norway and followed up at our hospital.

Results: 53 women gave birth to 57 live-born children, eight of whom were HIV-infected. The mothers of 4 HIV-infected children were treated with zidovudine monotherapy during their pregnancy. Out of the 12 children delivered by elective caesarean section and the 17 children (8 delivered by elective caesarean section) with mothers receiving antiviral combination therapy, none were HIV-infected. HIV-RNA was measured at the time of birth in 16 women; 8 had viral loads of less than 50 copies/ml and 8 had viral loads at the time of delivery between 50 and 57 100 copies/ml, but none of these 16 transmitted the virus to their children. None of the mothers breast-fed.

Interpretation: Transmission of HIV from mother to child was associated with insufficient or no antiviral therapy of mother and child. The effect of elective caesarean section could not be separated from the effect of antiviral therapy. We did not find any association between transmission of HIV and prematurity, development of immunodeficiency in the mother, special risk group status, or early membrane rupture.