Controversy has arisen concerning whether gender influences the prognosis after myocardial infarction. Although some studies have shown there to be no difference between the sexes, most have indicated a worse prognosis for women, attributing this to differences in baseline characteristics. It has been further suggested that black women have a particularly poor prognosis after infarction. To determine the contribution of gender and race to the course of infarction, 816 patients with confirmed myocardial infarction who were enrolled in the Multicenter Investigation of the Limitation of Infarct Size (MILIS) were analyzed. Of those patients, 226 were women and 590 were men, 142 were black and 674 were white. The cumulative mortality rate at 48 months was 36% for women versus 21% for men (p less than 0.001, mean follow-up 32 months). The cumulative mortality rate by race was 34% for blacks versus 24% for whites (p less than 0.005). Both women and blacks exhibited more baseline characteristics predictive of mortality than did their male or white counterparts. It was possible to account for the greater mortality rate of blacks by identifiable baseline variables; however, even after adjustment, the mortality rate for women remained significantly higher (p less than 0.002). The poorer prognosis for women was influenced by a particularly high mortality rate among black women (48%); the mortality rate for white women was 32%, for black men 23% and for white men 21%. The mortality for black women was significantly greater than that of the other subgroups. Thus, findings in the MILIS population indicate that the prognosis after myocardial infarction is worse for women, particularly black women.