Today is International Women’s Day. One way to honor women is to share life-saving knowledge. So let’s talk about venous blood clots because far too many women do not realize they are uniquely at risk for developing this common, potentially life-threatening condition.
What is it?
Venous thromboembolism (VTE) is a blood clot which forms in a deep vein of the body. It may go by several names depending on the physical location of the clot: deep vein thrombosis (DVT), pulmonary embolism (PE), sinus vein thrombosis (SVT), cerebral vein thrombosis(CVT), portal vein thrombosis (PVT), mesenteric vein thrombosis (MVT)
Each year, 10 million people worldwide experience venous thromboembolism (VTE). It is a leading cause of death and disability in both low-income and high-income countries. (7)
- In the United State alone, deaths from venous thromboembolism (VTE) are greater than those of AIDS, breast cancer, and crashes combined.
- In Europe, VTE causes half a million deaths annually.
Effective prevention strategies exist. Yet studies show few people worldwide even know what VTE is or how it can be prevented.
How do they impact women?
While venous blood clots affect both men and women, there are unique considerations for women:
- Blood clots can be life-threatening during pregnancy and are the leading cause of maternal death in the United States. (1)
- A woman is at increased risk for developing blood clots during pregnancy and that risk remains elevated for up to six-weeks following childbirth. Pregnancy increases the risk of a blood clot fivefold, with the risk even higher in the postpartum time period. (2)
- Post-menopausal women undergoing hormone replacement therapy have a two to four fold increase in the risk for clots. (3)
- Women with a clotting disorder (thrombophilia) have increased clot risk. About 8% of the US population is estimated to have a clotting disorder and a clotting disorder is found in upwards of 50% of women who have a blood clot during pregnancy.
- Women with a clotting disorder experience a higher rate of pregnancy complications including repeated miscarriage or stillbirth.(4)
- Estrogen containing oral contraceptives increase clot risk. Some contraceptives significantly increased risk more than others, 2-3x more. More information on specific contraceptives and clot risk. (5)
- Cancer patients are at increased venous clot risk. Cancer, chemotherapy and surgery can each increase clot risk. Women treated with tamoxifen to prevent or treat breast cancer are also at increased risk. (6)
What can you do?
Educate yourself and then pass along what you’ve learned to those persons closest to you. If you’ve been impacted by blood clots, share your story. Silence about venous blood clot risk helps no one. If we wish to save lives, we first must talk openly about it.
Above all, know the symptoms, risk factors and prevention strategies for the most common form of venous blood clots, deep vein thrombosis and pulmonary embolism.
How can you learn more?
For more information about clotting concerns unique to women:
Women and blood clots – from the National Blood Clot Alliance and the Rowan Foundation
Thrombophilia and pregnancy – from the March of Dimes
Contraceptives and blood clots – From the University of North Carolina’s Clot Connect campaign
Pregnancy and blood clots – from Duke University’s This is Serious campaign
Cancer and blood clots – from Duke University’s This is Serious campaign
Clinical practice bulletins and guidelines:
ACCP: VTE, Thrombophilia, Antithrombotic Therapy, and Pregnancy: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines Bates et al Chest. 2012;141(2_suppl):e691S-e736S
ACOG: Practice Bulletin 123: Thromboembolism in Pregnancy Guidelines from the American College of Obstetricians and Gynecologists regarding the prevention, management and treatment of blood clots during pregnancy. Obstetrics & Gynecology. 118(3):718-729, September 2011. Note: journal license required to view full article
ACOG: Practice Bulletin 124: Inherited thrombophilias in Pregnancy Review of common thrombophilias and their association with maternal venous thromboembolism risk, adverse pregnancy outcomes, indications for screening to detect these conditions and management options during pregnancy. Obstetrics & Gynecology. 118(3):730-740, September 2011. Note: journal license required to view full article.
1. Berg CJ, Atrash HK, Koonin LM, Tucker M. “Pregnancy-related mortality in the United States 1987-1990”. Obstet Gynecol 1996;88(2):161-7 Also see Marik. P.E. and Plante, L.A. “Venous Thromboembolic Disease and Pregnancy”. New England Journal of Medicine, volume 359, number 19, November 6, 2008, pages 2025-2033.
2.Heit JA, Kobbervig CE, James AH, Petterson TM,Bailey KR, Melton LJ, 3rd. Trends in the incidenceof venous thromboembolism during pregnancy or postpartum: a 30-year population-based study. Ann Intern Med 2005;143(10):697-706
3. Surgeon General’s Call to Action to Prevent Deep Vein Thrombosis and Pulmonary Embolism US Department of Health and Human Services 2008
4. March of Dimes
6. NBCA, Cancer and Blood Clots, https://www.stoptheclot.org/faq_blood_clots_cancer.htm
7. Thrombosis: a major contributor to the global disease burden. Journal of Thrombosis and Haemostatis, 12: 1580-1590 Oct 2014