The AmRo study: pregnancy outcome in HIV-1-infected women under effective highly active antiretroviral therapy and a policy of vaginal delivery.

OBJECTIVE: To explore pregnancy outcome in HIV-1-positive and HIV-negative women, and mother-to-child transmission (MTCT) according to mode of delivery under effective highly active antiretroviral therapy (HAART).

DESIGN: Cohort of 143 pregnant HIV-1-infected women including a matched case-control study in a 2:1 ratio of controls to cases (n=98).

SETTING: Academic Medical Center in Amsterdam and Erasmus Medical Center in Rotterdam, the Netherlands.

POPULATION: Consecutive referred HIV-1 infected pregnant women treated with HAART and matched control not infected pregnant women.

MAIN OUTCOME MEASURES: MTCT, preterm delivery, low birthweight, pre-eclampsia.

RESULTS: MTCT was 0% (95% CI 0-2.1%). Seventy-eight percent of HIV-1-infected women commenced and 62% completed vaginal delivery. The calculated number of caesarean sections needed to prevent a single MTCT was 131 or more. Preterm delivery rates were 18% (95% CI 11-27) in women infected with HIV-1 and 9% (95% CI 5-13) in controls (P=0.03). HAART used at <13 weeks of gestation was associated with a 44% preterm delivery rate compared with 21% when HAART was started at or after 13 weeks and 14% in controls. (Very) low birthweight and incidence of pre-eclampsia were not different between HIV-1 and controls.

CONCLUSIONS: We have not demonstrated any MTCT after vaginal delivery in women effectively treated by HAART. The HAART-associated increase in preterm delivery rate is mainly seen after first trimester HAART use.