Abstract: Objective To examine delivery conditions and pregnancy outcomes among human immunodeficiency virus(HIV)infected pregnant women.Methods This study was a prospective observational cohort study.From 2005-2011,1 187 HIV infected mothers and 1205 newborns were investigated face to face in 7 counties or districts with high HIV prevalence.Results Among the 1 187 pregnant women,hospital delivery accounted for 96.0%(1 139/1 187).The ratio of cesarean section among the women was 39.1%(456/1 166).The rate of pregnancy complications decreased from 34.1% to 24.3% from 2005 to 2011(χ²=6.856,P=0.009).Neonatal death rate was between 0 and 0.5%.There were no siginificant differences observed in annual variation trend for delivery status and pregnancy outcome among the HIV-infected pregnant women.ConclusionAlthough maternal delivery outcome and neonatal health being improved continuously,the incidences of some obstetric factors such as cesarean delivery,obstetric risk operation,pregnancy complications which may increase the risk of mother-to-child transmission are still high.