Figure 1.

Time course of gestation in relation to the parasitemia of mice acutely infected with T. cruzi. Female BALB/c mice were infected at day 0. The black dotted line represents the parasitemia of gravid mice (n = 65, geometric mean ± SEM). They were mated from days 7 until 10 after infection. Areas indicate important time points of gestation. According to the day after infection at which the vaginal plug was observed, the first day of gestation (G1, gray bars) occurred before circulating parasites were detectable, implantation (G4.5, dotted bars) took place at the beginning of the parasitemic phase, the complete formation of the placenta (G9.5, oblique lined bars) occurred during the ascending phase of the parasitemia, and delivery (G20, horizontal lined bars) occurred at the peak of parasitemia. Mated mice were either killed at G9, G17, or G19, or allowed to deliver.