Cafferata ML, Toscani MA, Althabe F, et al. - Assuming that among Trypanosoma cruzi seropositive women, major side effects may reduce and compliance may improve with providing a short and low dose benznidazole (BZN) treatment, researchers seek to determine its efficacy to reduce T. cruzi parasitic load compared with the standard 60d/300 mg course. They propose to compare a short low dose 30-day treatment with BZN 150 mg/day (30d/150 mg) vs BZN 60d/300 mg via performing a double-blinded, non-inferiority randomized controlled trial. T. cruzi seropositive women with a live birth will be recruited during the postpartum period in Argentina, and these women were not treated previously. These will then be randomized at 6 months postpartum, and followed up with the following specific aims: Specific aim 1: to determine the effect of BZN 30d/150 mg vs 60d/300 mg preconceptional treatment on parasitic load estimated by the frequency of positive Polymerase Chain Reaction (PCR) (primary outcome) and by real-time quantitative PCR (qPCR), immediately and 10 months following treatment. Specific aim 2: to estimate the frequency of serious adverse events and/or any adverse event resulting in treatment interruption.