OBJECTIVE: The purpose of this study was to generate the first estimates of the lifetime medical costs of treating women with either cardiovascular disease ("CVD"), diabetes, or stress urinary incontinence ("SUI"). METHODS: Women under age 65 years, who have been treated for CVD, diabetes, or SUI, were identified using administrative medical claims data from a large employer (n>100,000). A case-control methodology was used to estimate the annual medical costs of these women. Annual estimates were then calculated for women 65 years and older based on a set of assumptions and published government statistics. An incidence-based methodology with steady-state assumptions was used to project these annual costs to the lifetime medical costs of treating women with CVD, diabetes, or SUI. Costs are incremental and are estimated as the additional costs incurred by patients, as compared to demographically similar controls without the condition. The methodology used does not account for cost inflation, technological change, or the time value of money. RESULTS: The lifetime costs associated with CVD, diabetes, and SUI are substantial. CVD is the most expensive condition on a lifetime basis, followed by diabetes, and then SUI. The incremental lifetime medical cost of treating a woman with CVD (in 2002 dollars) is $423,000. The lifetime cost of treating a woman with diabetes is $233,000 and with SUI is $58,000. CONCLUSIONS: These findings are the first estimates of the lifetime medical cost burden of three chronic conditions suffered by women. The levels of these costs suggest the need for further research and methodological refinements to increase awareness of the lifetime burden of chronic conditions.