The Effect of the Mini-pill on Blood Factors in Women at Increased Risk for Forming Blood Clots
We propose a prospective cohort study to assess the effect of the progesterone only contraceptive pill (minipill) on coagulation parameters known to be associated with risk of thrombosis (blood clots) in women who are at increased risk for forming blood clots. We plan to recruit women with a history of venous thromboembolism (VTE, blood clot in a vein) and women with a history of blood tests which demonstrate an increased risk of thrombosis who desire contraception.
Women enrolled in this study will undergo phlebotomy (blood draw) at baseline (prior to starting the minipill), one and three months. Stored samples will be used to measure D-dimer, C-reactive protein (CRP), antithrombin (AT), factor VIII, free and total protein S, fibrinogen, von Willebrand factor (vWF) and normalized activated protein C sensitivity ratio (nAPCsr). Both groups will undergo a general physical and GYN exam prior to enrollment. This exam and the blood testing will be provided free of charge. Patients will not be prescribed the minipill after completion of the study and will be advised to consult with their primary care physician or hematologist if they wish to continue this medication.
|Study Design:||Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Prevention
|Official Title:||The Effect of Oral Norethindrone on Coagulation Parameters in Women at Increased Risk for Venous Thromboembolic Events|
- The primary outcome of this study will be change in coagulation parameters. The proposed sample size of 20 subjects was derived based on having sufficient power to detect a 40% change in the variable D-dimer, a lab measurement. [ Time Frame: 2 years ] [ Designated as safety issue: No ]
|Study Start Date:||December 2007|
|Estimated Study Completion Date:||July 2009|
|United States, Vermont|
|University of Vermont|
|Burlington, Vermont, United States, 05405|
|Principal Investigator:||Kristen P Wright, MD||University of Vermont|
|Principal Investigator:||Julia V Johnson, MD||University of Vermont|