This study sought to describe condom use over time in new and established adolescent relationships. The outcome variable was time (in days) until first unprotected coital event. Analyses involved comparisons of Kaplan-Meier survival curves and Cox proportional hazards models. Survival functions for the 2 relationship groups were significantly different. However, by 21 days the curves had converged: 43% of new and 41% of established relationships involved no unprotected coital events. Time to first unprotected coital event was significantly longer in new than in established relationships. Prolongation of condom use in ongoing relationships may be a useful intervention to prevent sexually transmitted diseases.
