Duration of membrane rupture and risk of perinatal transmission of HIV-1 in the era of combination antiretroviral therapy

OBJECTIVE: The objective of the study was to determine whether the duration of membrane rupture of 4 or more hours is a significant risk factor for perinatal transmission of human immunodeficiency virus (HIV) in the era of combination antiretroviral therapy (ART). STUDY DESIGN: This was a prospective cohort study of 717 HIV-infected pregnant women-infant pairs with a delivery viral load available who received prenatal care and delivered at our institution during the interval 1996-2008. RESULTS: The cohort comprised 707 women receiving ART who delivered during this interval. The perinatal transmission rate was 1% in women with membranes ruptured for less than 4 hours and 1.9% when ruptured for 4 or more hours. For 493 women with a delivery viral load less than 1000 copies/mL receiving combination ART in pregnancy, there were no cases of perinatal transmission identified up to 25 hours of membrane rupture. Logistic regression demonstrated only a viral load above 10,000 copies/mL as an independent risk factor for perinatal transmission. CONCLUSION: Duration of membrane rupture of 4 or more hours is not a risk factor for perinatal transmission of HIV in women with a viral load less than 1000 copies/mL receiving combination ART.