Asking Only “Did You Use a Condom?” Underestimates the Prevalence of Unprotected Sex Among Perinatally HIV Infected and Perinatally Exposed But Uninfected Youth … See the original article here: Asking Only “Did You Use a Condom?” Underestimates the Prevalence of Unprotected Sex Among Perinatally HIV Infected and Perinatally Exposed But Uninfected Youth