MATERNAL VIRUS LOAD DURING PREGNANCY AND MOTHER-TO-CHILD TRANSMISSIONOF HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 - THE FRENCH PERINATAL COHORT STUDIES

Virus load in pregnancy and its relation to mother-to-child human immu nodeficiency virus (HIV) transmission were studied prospectively. From 1989 to 1994, 320 HIV-infected women from 18 centers had plasma sampl es stored. Among women not receiving antiretroviral therapy, the polym erase chain reaction RNA level was 3.6 log at delivery, and 15% of wom en had levels below the detection limit. There was no variation during pregnancy. Women born in sub-Saharan Africa had lower RNA levels, alt hough their CD4 cell distribution did not differ from that in other wo men. Among 236 evaluable children, 19% +/- 5% were infected. Transmiss ion occurred in 12% of cases (confidence interval, 5%-22%) with < 1000 copies/mL versus 29% +/- 10% of those with > 10,000 copies/mL (P < .0 2). Maternal virus load appears strongly related to HIV transmission t o the child.