Pregnancy outcome and placental weights: their relationship to HIV-1 infection.

The relationship between placental characteristics, including weight and inflammation, and pregnancy outcome was examined as part of a case control study looking into the impact of maternal HIV-1 infection on pregnancy outcome. Cases defined as low birth weight (< 2500g) or stillbirth deliveries, were compared to controls defined as mothers who delivered a live born neonate weighing 2500g or more. The mean placental weight and the mean foetal/placental weight ratio were significantly lower in cases (n = 253) than in controls (n = 216) (p < .05). Placental inflammation (chorioamnionitis) was significantly associated with prematurity (p < .001) and with stillbirth (p < .05), maternal HIV-1 antibody being a risk factor for chorioamnionitis in the preterm group. These data support a correlation between placental weight and pregnancy outcome, and suggest that maternal HIV-1 infection is a risk factor for chorioamnionitis in HIV-1 seropositive preterm deliveries.