Plasminogen-activator-inhibitor type 1 (PAI-1) is a negative prognostic factor in ovarian carcinoma. The 4G/5G promoter polymorphism varies PAI-1 transcription and causes an increase in PAI-plasmalevels when the 4G allel is present. We investigated the possible relation between G/5G promoter polymorphism and the chance for the disease, age at diagnosis, tumor histology, grading, and prognosis on the basis of blood samples from patients with ovarian cancer and controls using PCR analysis. Several, predominantly subsignificant, tendencies were observed. Interestingly, patients with a G1 or G2 tumor had a significantly worse prognosis when the 4G-allel was present than those lacking the 4G-allel. This supports the hypothesis, that the 4G-allel causes higher PAI-1 expression and a more malignant phenotype of ovarian cancer.