Preventing mother-to-child transmission of HIV-1

Over the last 10 years, interventions to reduce the transmission of HIV-1 from mother to child have been extremely successful in the UK in pregnant women aware of their HIV status. Judicious use of pre-labour caesarean section, formula feeding and antiretroviral therapy has reduced transmission to less than 1% in these mothers and their infants. Before the introduction of such interventions, natural history data showed vertical transmission rates of around 25%. The risk of transmission from mother to child has been associated with advanced maternal HIV disease, maternal plasma HIV viral load and CD4 lymphocyte count, mode of delivery, duration of rupture of membranes, prematurity and breast-feeding. Attention is now turning to the minimisation of possible drug side effects in both mother and infant, as women are increasingly conceiving on combination antiretroviral therapy. The reduction of mother-to-child transmission of HIV following current UK guidelines is discussed.