Women & Warfarin

Publication Date: 
Wed, 05/01/2013
By: Alere Staff

If you’ve been prescribed warfarin, one of the first questions you’ll be wondering is how warfarin will affect your short and long-term decision making. In the past, men have more often been prescribed warfarin to prevent ischemic stroke than women. For women prescribed warfarin, their time in INR (International Normalized Ratio) target range, or a measure of how well warfarin is working, is consistently less than men.1

Bias by gender statistics
  • Women suffer more ischemic strokes than men.2
  • Women spend less time in their target range while on warfarin.2
  • Women are almost 50% less likely to be referred to a specialized clinic.
  • Women are diagnosed with atrial fibrillation at an older age than men.3
  • Women under-performed by 5% time in range compared to men.1
There are a few behaviors that increase chances of safe and successful long-term warfarin use:
  • Consistent dietary choices. Good health includes a healthy diet, quality sleep, exercise and attention to bone health. Consistent dietary vitamin K, D and calcium are important decisions to discuss with your doctor or nurse. Vitamin D helps your body absorb the calcium you eat or drink. Some calcium supplements can interact with warfarin, discuss which product is right for you.
  • Post-menopause. Fall prevention is a common goal for post-menopausal women. Regular exercising and stretching will improve your strength and balance and reduce your risk of falling. Safe warfarin use is within your reach by remaining consistent in your diet and medication use, talking with your doctor or nurse regularly, and increasing your testing frequency to avoid surprise rises or falls in your INR blood test results.
  • Test frequently. Studies have shown that more frequent testing can improve your safety on warfarin.1 Increasing your testing frequency will allow you to evaluate foods, exercise, or hormonal replacement products and how warfarin reacts to your choices.
  • Medications and birth control. Talk to your doctor about what prescription and nonprescription medications, vitamins, and nutritional supplements you are taking or plan to take. Some medications, like birth control pills (oral contraceptives) can interact with warfarin.4
  • Pregnancy. Women taking warfarin should use reliable birth control, since warfarin is known to cause birth defects.4 If you are taking warfarin and want to become pregnant, talk to your doctor about alternatives before you become pregnant.

When you are taking warfarin it is especially important to maintain a healthy living and stay consistent. Consistency is an essential behavior for being safe and successful while on warfarin. If you are concerned about your stroke or heart disease risk, or are currently taking warfarin, talk to your doctor.

  1. Ansell, J. March 2012. Patient Self-Testing: Real-World Experience Within a Comprehensive Support Service Represents a New Standard of Care, Attaining High Quality Anticoagulation Control. Poster presented at: American College of Cardiology.
  2. Olshansky , B. et al. The Atrial Fibrillation Follow-Up Investigation of Rhythm Management (AFFIRM) Study. J Am Coll Cardiol, 2004; 43:1201- 1208, doi:10.1016/j.jacc.2003.11.032
  3. Hagens VE, et. Al. The RACE study in perspective of randomized studies on management of persistent atrial fibrillation. Card Electrophysiol Rev. 2003 Jun;7(2):118-21.
  4. Bristol-Myers Squibb Company. Medication Guide for Coumadin Tablets and Coumadin for Injection [Package Insert]. Princeton, NJ: Bristol-Myers Squibb Company. 2009.