Medically reviewed by Sophia Yen, MD, MPH – Written by Pandia Health Editorial Team

Hormonal Birth Control Products and the Risk of Blood Clot Formation

Millions of women use hormonal birth control methods to prevent unintended pregnancy, regulate hormones, and control the symptoms of PCOS. Although birth control pills and other hormonal contraceptive methods are proven safe and effective for the vast majority of women, not every woman can safely take hormonal birth control. Unfortunately, some birth control products can increase the risk of blood clots developing in women with particular risk factors. The following article will explore what blood clots are, why they are dangerous, and how birth control affects their formation.

What is a blood clot?

Human blood is comprised of several clotting agents that give blood its consistency, and also allow the body to repair itself if someone gets cut or injured. However, some people can experience increased clotting factors in their blood. The hormone estrogen is known to increase the blood’s ability to coagulate and therefore, clot.

Blood clots make it difficult or impossible for blood to flow through tiny veins, arteries, and capillaries throughout the body. When a blood clot forms, it can become stuck, and cause a heart attack or a stroke, which can be fatal or lead to permanent disability.

Birth Control and Blood Clots

There are two types of blood clots – deep vein thrombosis, or DVT, and pulmonary embolisms. In DVT, a clot forms inside the deepest veins of the body, which are located in the legs or the arms. The signs of DVT include:

  • Swelling where the clot has formed.
  • Leg or arm pain and tenderness near the clot that feels similar to a cramp.
  • Red or blue skin discoloration at the clot site.
  • The clot site is warm to the touch.

Sometimes, the clots that form in DVT can break apart and travel up toward the lung. This is called a pulmonary embolism and is often fatal. The symptoms of a pulmonary embolism include:

  • Shortness of breath
  • Chest pains that get worse when a person takes a deep breath.
  • Accelerated heart rate
  • A bloody cough

When someone experiences any of the symptoms of DVT or a pulmonary embolism, they need to go to the ER immediately.

How do hormones impact the formation of blood clots?

Hormonal birth control pills are some of the most common contraceptive methods uses in the U.S. Birth control pills themselves do not cause blood clots to form directly. But they can increase the chances of blood clot formation as much as three to four times. This happens because the hormones present in some birth control products, including the pill, can influence blood coagulation factors.

Most hormonal birth control pills contain a combination of progesterone and synthetic estrogen hormones. These hormones increase the clotting factors in the blood. This is also why women who are pregnant are at increased risk of suffering from blood clots. Only about one in 1000 women who take hormonal birth control pills are at risk of having a blood clot form.

But women with a family or personal history of blood clots, older women over age 35, and women who smoke have a much higher risk of having a blood clot form while taking the pill or the birth control patch. Women in these groups should not take hormonal birth control pills that used combined estrogen and progesterone. Both the patch, the ring, and combination oral contraceptives can increase the blood’s ability to clot and lead to DVT or pulmonary embolism.

What can decrease the risk of having a blood clot form while taking birth control pills or patches?

Some women may take an anticoagulant medication, and taking an anticoagulant while also taking hormonal birth control decreases the risk of having a dangerous blood clot form. But women who are not taking anticoagulants and also have an increased risk of blood clot formation have more limited choices for birth control.

Recent research also indicates that some types of hormonal contraceptives that contain drospirenone and desogestrel can increase the blood’s ability to coagulate. Those contraceptives are:

  • Yaz
  • Yasmin
  • Desogen

What types of birth control can women concerned about blood clots take?

Estrogen is the biggest culprit behind women’s increased risk of having blood clots form while taking the pill and also while pregnant. However, progesterone and synthetic progesterone hormones do not raise the risk of having the blood coagulate to unsafe levels. Women can take progestin-only pills, also known as mini-pills if they are concerned about blood clots.

Progestin-only pills include:

  • Micronor
  • Nor-Q.D.
  • Ovrette

Also, IUDs, or intrauterine devices, do not increase the risk of blood clots. IUDs are also long-lasting and are easy to remove if a woman wishes to get pregnant or stop using the IUD for any reason. IUDs can last up to ten years and are some of the most effective, long-lasting birth control products on the market. Both the Mirena and the copper IUD do not increase the risk of blood clots.

The birth control shot is also safe for women with concerns regarding blood clots. The shot uses a dose of progestin that is given every three months to prevent ovulation from occurring.

Other barrier contraceptive methods are safe for women to use if they have a history of blood clots, smoke, or are over age 35. Condoms, diaphragms, and cervical caps are safe to use. Emergency contraceptives do not contain estrogen and are also safe to use.

What should women do if they are concerned about blood clots?

As always, it’s crucial that women thoroughly discuss their personal health history and immediate family health history when trying any new medication, not just hormonal birth control. When looking into different types of prescription birth control methods to try, women can significantly benefit from doing their own research and speaking to their doctors about their needs and concerns. It’s important for women to take charge of their reproductive health.

Not only can hormonal birth control prevent unintended pregnancy, but it can also help women regulate their hormones, alleviate menstrual pains, and also prevent endometriosis and PCOS symptoms from flaring up. Please sign up with Pandia Health today to find out what types of long-lasting and effective birth control methods are right for your lifestyle and health needs.

Disclaimer: The views expressed in this article intend to inform and induce conversation. They are the views of the author and do not necessarily represent the views of Pandia Health, and are for informational purposes only, even if and to the extent that this article features the advice of physicians and medical practitioners. This article is not, nor is it intended to be, a substitute for professional medical advice, diagnosis or treatment, and should never be relied upon for specific medical advice.