From July 1, 1990, to July 1, 1993, we analyzed the results of fibrinogen levels, prothrombin time, and partial thromboplastin time in patients with severe preeclampsia, at least one platelet count less than 100,000/microL, and no signs of abruption or hemorrhage. Analysis was by Pearson's correlation coefficient and Wald's sequential analysis. We analyzed 162 blood collections from 48 patients. There was no correlation between the level of thrombocytopenia and the levels of prothrombin time, partial thromboplastin time, or fibrinogen. None of the samples from any of the preeclamptic patients demonstrated an abnormal prothrombin time or partial thromboplastin time.