To assess whether the incidence of invasive cervical cancer (ICC) has changed as a result of highly active antiretroviral therapy (HAART), we conducted a prospective cohort study on the incidence of ICC before and after the introduction of HAART among Italian women with a known duration of HIV infection. We estimated the incidence per 1000 person years of ICC as a first AIDS-defining disease for the periods 1981 through 1991, 1992 through 1995, and 1996 through 1998. We also estimated the incidence of other first AIDS-defining diseases. Kaplan-Meier and Cox models were applied to compare the periods 1981 through 1995 and 1996 through 1998 in terms of cumulative incidence and relative hazards (RHs). The analysis included 483 women (median follow-up: 7 years). In the period 1981 through 1995, a trend of increase was observed in the incidence of ICC and other AIDS-defining diseases; this trend has continued only for ICC, whereas the incidence of other AIDS-defining diseases has decreased since 1996. Compared with 1981 through 1995, the RH of ICC for 1996 through 1998 was 7.41 (95% confidence interval [CI]: 1.21--45.44); when adjusting for age at HIV seroconversion, the RH decreased to 4.75 (95% CI: 0.80--28.24). It remains to be determined whether the continued increase in ICC incidence after the introduction of HAART is attributable to a decreasing competitive mortality from other AIDS-defining diseases among HIV-infected women.