Objectives: This study sought to describe condom use over time in new and established adolescent relationships.
Methods: 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.
Results: 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.
Conclusions: Prolongation of condom use in ongoing relationships may be a useful intervention to prevent sexually transmitted diseases.