Treating menstruating women with thrombolytic therapy: insights from the global utilization of streptokinase and tissue plasminogen activator for occluded coronary arteries (GUSTO-I) trial

J Am Coll Cardiol. 1995 Dec;26(7):1651-6. doi: 10.1016/0735-1097(95)00386-x.


Objectives: The purpose of this study was to examine the clinical implications of administering thrombolytic therapy to menstruating women with acute myocardial infarction.

Background: Although anecdotal case reports have suggested that thrombolytic therapy is safe during menstruation, the risk of increased bleeding in menstruating women receiving such therapy is poorly defined.

Methods: We identified menstruating women who received thrombolytic therapy by soliciting information on all North American women enrolled in the GUSTO-I trial and then collected additional information about them with use of a one-page data form. We compared the characteristics and outcomes of these women with other GUSTO-I patient populations, including all North American women below the median age of menopause, all women and all patients.

Results: The median age of the 12 menstruating women was 46 years; 75% were cigarette smokers. The median hospital stay was 7 days, 2 fewer than the overall stay in GUSTO-I. None of these women died or had a stroke or severe bleeding. Three patients (25%) had moderate bleeding (vaginal in two patients [66%]) that required transfusion compared with 11% of all GUSTO-I patients and all North American premenopausal women (p = 0.13) and 17% of all female GUSTO-I patients (p = 0.47). Because of the small sample size of 12 women, the power was low (0.37) to detect the observed difference in moderate bleeding. The median nadir hematocrit was 33% in the menstruating women compared with 34% in the premenopausal women and all women. The median time from symptom onset to treatment for the 12 women was 3.7 h, which was 0.9 h longer than the overall median in the trial (p = 0.09).

Conclusions: Although there was no statistically significant increase in bleeding risk during menstruation, this fact may be a result of low statistical power rather than a lack of effect. Thus, the results suggest that there may be a clinically significant increase in the risk of moderate bleeding. Nevertheless, the GUSTO-I experience is consistent with the concept that the lifesaving benefit of thrombolytic therapy for acute myocardial infarction should generally not be withheld because of active menstruation.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Coronary Disease / drug therapy*
  • Female
  • Hemorrhage / chemically induced
  • Humans
  • Length of Stay
  • Menstruation*
  • Middle Aged
  • Plasminogen Activators / therapeutic use*
  • Streptokinase / adverse effects
  • Streptokinase / therapeutic use*
  • Thrombolytic Therapy* / adverse effects
  • Tissue Plasminogen Activator / adverse effects
  • Tissue Plasminogen Activator / therapeutic use*


  • Streptokinase
  • Plasminogen Activators
  • Tissue Plasminogen Activator