[Vertical HIV-I-transmission. I. Risk and prevention in pregnancy].

Without anti-HIV treatment, mother to child HIV-I transmission occurs in 15-30% of HIV positive pregnancies. Transmission occurs mostly in the last trimester or at birth. The maternal virus load in the last trimester and around birth is strongly related to the risk of HIV transmission to the child. This risk can be reduced during pregnancy by anti-HIV treatment and in certain cases by performing a caesarean section. It is recommended to determine the plasma virus load several times during pregnancy. If the virus load is found to be high, measurement of plasma anti-HIV drug concentrations and anti-HIV drug resistance may prompt modification of the anti-HIV drug regimen with the objective of achieving maximal suppression of virus replication in the last trimester.