We characterized factors and temporal trends associated with discontinuation of highly active antiretroviral therapy (HAART) among 936 HIV-infected women enrolled in the Women's Interagency HIV Study. A multivariate analysis of post-HAART initiation exposures found that high HIV RNA levels (relative hazard [RH] = 1.36, P < 0.001) and high depressive symptom scores (RH = 1.53, P = 0.012) were associated with HAART discontinuation. The adjusted hazard of discontinuation was higher in the 2 most recent calendar periods compared with the first (RH = 1.61, P = 0.026; RH = 1.56, P = 0.074, respectively). The increasing risk of HAART discontinuation in recent calendar periods and changes in the clinical factors associated with discontinuation reflect ongoing and dynamic shifts in the approach to HAART utilization.