Risk factors and consequences of congenital Chagas disease in Yacuiba, south Bolivia

To determine the risk factors of congenital Chagas disease and the consequences of the disease in newborns. Study of 2712 pregnant women and 2742 newborns in Yacuiba, south Bolivia. Chagas infection was determined serologically in mothers and parasitologically in newborns. Consequences of congenital Chagas disease were assessed clinically. The prevalence of Chagas disease in pregnant women was 42.2%. Congenital transmission was estimated at 6% of infected mothers leading to an incidence rate of 2.6% among newborns. Main risk factors of congenital transmission were mothers' seropositivity and maternal Trypanosoma cruzi parasitaemia. Parity was higher in infected than in non-infected mothers, but it was not associated with the risk of congenital transmission. The rate of congenital infection was significantly higher in newborns from multiple pregnancies than in singletons. However, we did not observe statistically significant consequences of Chagas disease in newborns from single pregnancies or among twins. The main risk factors for congenital transmission were infection and parasitaemia of mothers. Consequences of the disease seemed mild in newborns from single pregnancies and perhaps more important in multiple births.