Blood Clots, Birth Control and Being Aware

young woman with pillsLast week I got a call from a patient who was really shaken up by the news that 39-year-old fashion stylist Annabel Tollman had died and there were reports that the cause of death was a blood clot.

Was it her birth-control pills? Should she go off?

Let me start by saying I have no knowledge of Ms. Tollman’s personal medical history, but I can tell you that in most cases, people who develop a blood clot have at least one risk factor. And while taking birth control pills is the most well-known risk factor, it is not the most common risk factor.

Death from a blood clot can be the result of a deep vein thrombosis (DVT), a blood clot that forms in a leg, thigh or pelvic vein. The danger of a DVT is that it can break off and travel other places, such as the lung, resulting in a pulmonary embolism, a serious and potentially fatal complication responsible for over 50,000 deaths in the US each year.

It’s true that women on hormonal contraception containing estrogen may be at increased risk for developing a potentially fatal DVT, but any excess estrogen increases risk, and it may be more likely to develop a blood clot during pregnancy or after delivery than when taking birth control.

In any circumstance, blood clots in young women are very rare events. Knowing the actual numbers helps to keep things in perspective.

  • The likelihood of a blood clot if not on birth control pills is 2-3 for every 10,000 women.
  • The likelihood of a blood clot when taking birth control pills is 3-9 for every 10,000 women.
  • The likelihood of a blood clot during pregnancy is 5-20 for every 10,000 women.
  • The likelihood of a blood clot post partum is 40-65 for every 10,000 women.

Pills and pregnancy aren’t the only risk factors. A genetic predisposition, recent surgery, cancer, prolonged immobilization, age (over 50), smoking and obesity may also have an impact.

Here’s how to reduce your risk:

Know Your Family History
Some people are genetically programmed to form blood clots more easily. If there are a number of family members who have had strokes, DVTs or pulmonary embolism, get tested to see if you have an inherited thrombophilia.

You Can’t Pick Your Relatives, But You Can Pick Your Contraception
Women who are smokers or obese, particularly if they are over 35, should not use a contraception that contains estrogen. If you have risk factors, use a different method of contraception such as one that is non-hormonal or contains progestin only.

Keep Moving
Sitting for long periods of time is problematic since immobility allows blood to pool in leg veins. It used to be that the usual person who developed a DVT was an overweight, smoking truck driver, but there are now a disproportionate number of people that develop a DVT during long plane rides.

Short of upgrading to first class, there are strategies to reduce risk. Change positions frequently, don’t cross your legs, and flex, and extend your ankle and knees periodically. Even climbing over your seatmate to get to the bathroom can get the blood moving through lower extremities.

Thromboembolic compression stockings may dramatically reduce the risk of DVT. While taking a sleeping pill is an appealing option during a long flight, spending hours immobilized in a coma like state is associated with a higher rate of clot formation.

Eighty percent of people that develop a DVT have at least one, and often more than one, risk factor. What that also means, is that 20% of people that develop a DVT have no known risk factors. It can happen to anyone, but fortunately, it doesn’t very often.