TIMING AND MECHANISM OF PERINATAL HUMAN IMMUNODEFICIENCY VIRUS-1 INFECTION

There is sufficient evidence indicating a higher vertical HIV-1 transm ission rate in the last trimester and during labour compared with the first trimester. Antiretroviral therapy either single or in combinatio n given to the mother during the last trimester and delivery can reduc e the viral load in the maternal circulation. Vertical HIV-1 transmiss ion during delivery can be minimized by appropriate timing and route o f delivery. Elective Caesarean section before the onset of labour with an intact bag of forewaters provides the least mother-to-fetus microt ransfusion compared to other modes of delivery. Since an effective com bination of HIV-1 immunoglobulin and HIV-1 vaccine given to the HIV-1 exposed newborns to prevent HIV-1 transmission similar to the viral he patitis B model is not firmly established at present, postexposure ant iretroviral prophylaxis and nonbreast-feeding are advocated for infant s born from the HIV-1 infected mothers. In cases of advanced stage of maternal HIV-1 infection, and in developing areas where malnutrition p revails, an adequate supply of essential micronutrients is proposed as an adjunctive measure to reduce HIV-1 perinatal transmission.