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The Effect of the Mini-pill on Blood Factors in Women at Increased Risk for Forming Blood Clots

The Effect of Oral Norethindrone on Coagulation Parameters in Women at Increased Risk for Venous Thromboembolic Events

Status
Terminated
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00580424
Enrollment
20
Registered
2007-12-24
Start date
2007-12-31
Completion date
2009-07-31
Last updated
2010-06-28

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Women's Health, Blood Coagulation Disorders

Brief summary

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.

Interventions

Norethindrone 0.35 mg orally daily

Sponsors

University of Vermont
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
PREVENTION
Masking
NONE

Eligibility

Sex/Gender
FEMALE
Age
18 Years to 52 Years
Healthy volunteers
No

Inclusion criteria

* 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. * Blood tests which demonstrate an increased risk of thrombosis include the following: * Hyperhomocysteinemia/MTHFR mutation * Prothrombin gene mutation * Factor V Leiden heterozygotes * Factor V Leiden homozygotes, antithrombin III mutation * Protein S deficiency and Protein C deficiency.

Exclusion criteria

* Women on current anticoagulation therapy * Women with a history of oral contraceptive related thrombotic events * Active or history of cigarette smoking within the past 6 months * Pregnancy * Active lactation * Known hypersensitivity to progestin * Any history of malignancy * History within the last three months of surgery or planning surgery during the study period * Undiagnosed vaginal bleeding * Active liver disease and history within the last 5 years of alcoholism or drug abuse. * Additionally, women must be greater than 3 months postpartum and have had two months without contraceptive hormones (such as the birth control pill) and 6 months without Depo-Provera use prior to enrollment.

Design outcomes

Primary

MeasureTime frame
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.2 years

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026