A primigravida in 2nd trimester became positive for toxoplasmosis. Veical transmission of toxoplasmosis MOST commonly occurs in which trimester?

In pregnancy, if the mother becomes infected during the first trimester, the incidence of transplacental infection is lowest (15%), but the disease in the neonate is most severe. If maternal infection occurs during the third trimester, the incidence of transplacental infection is greatest (65%), but the infant is usually asymptomatic at bih. Infected infants who are normal at bih may have a higher incidence of learning disabilities and chronic neurologic sequelae than uninfected children. Ref: Kim K., Kasper L.H. (2012). Chapter 214. Toxoplasma Infections. In D.L. Longo, A.S. Fauci, D.L. Kasper, S.L. Hauser, J.L. Jameson, J. Loscalzo (Eds),Harrison's Principles of Internal Medicine, 18e.