CD40LG and infection: We estimated the prevalence of transplacental infection and respective 95% confidence intervals (95% CI) and its association with risk factors using the odds ratio (or) with a <i>p</i>-value < 0.05 in infected neonates before and after 16 gestational weeks at maternal infection diagnosis.<h4>Results</h4>A total of 1142 neonates were surveyed, in which 496 were diagnosed with congenital toxoplasmosis (IgM positive), thus obtaining a prevalence of vertical transmission of 45.4%.