If you’re pregnant, you may be at an elevated risk for developing blood clots that could cause dangerous complications. Here’s what you need to know about thrombophilia in pregnancy.

Thrombophilia is a condition in which the blood has a higher tendency to clot. It can occur because the body produces too much of the protein that makes the blood clot or coagulate.

This means your blood tends to clot more readily than it should, which can be dangerous. A blood clot in the wrong place at the wrong time can cut off the oxygen supply to tissues that need it.

Also known as hypercoagulability, thrombophilia can pose many risks for both a pregnant person and their fetus. Here’s what you need to know about thrombophilia in pregnancy.

You might not know you have thrombophilia until you actually develop a blood clot. Then, the symptoms can depend on where the blood clot has formed.

Common symptoms of thrombophilia during pregnancy include:

There are two kinds of thrombophilia: acquired and genetic, or inherited. Several mutations can lead to genetic thrombophilia, with the most common type being the factor V Leiden mutation.

However, acquired thrombophilia is still the most common kind. It can be caused by:

  • cancer
  • long periods of immobility, such as prolonged bed rest
  • traumatic injury

During pregnancy, hormone levels surge. However, hormones also influence the blood’s ability to coagulate, and the hormones associated with pregnancy tend to increase the blood’s tendency to coagulate. This increases a pregnant person’s risk of developing blood clots, which can lead to serious complications.

The risk actually peaks around the time of delivery, but it doesn’t end there. In fact, research suggests pregnancy hormones increase the likelihood of thrombophilia for as long as 2 months into the postpartum period.

Having thrombophilia during pregnancy can raise the risk of experiencing certain complications, including deep vein thrombosis (DVT), a condition that occurs when a blood clot develops inside a deep vein. It causes pain, swelling, and tenderness, usually in the calf or lower leg.

Another possible serious complication from thrombophilia is pulmonary embolism (PE), which occurs when a blood clot breaks off and blocks an artery in a lung.

A pregnant person is also at greater risk of:

  • experiencing pregnancy loss
  • a stillbirth
  • placental abruption
  • preeclampsia if a blood clot develops and blocks a vein or artery

If you are diagnosed with thrombophilia during pregnancy, a doctor may suggest you take a blood thinner to reduce the likelihood of developing a dangerous blood clot. A commonly used anticoagulant medication is low-molecular-weight heparin.

Heparin is also given to pregnant people experiencing PE.

If you develop signs of deep vein thrombosis or pulmonary embolism while pregnant, you should seek medical care right away. Pulmonary embolism is one of the leading causes of death among pregnant people. A 2019 study suggests it accounts for about 9% of all pregnancy-related deaths in the United States. The research also suggests it’s more common among people who deliver by cesarean delivery, commonly known as a C-section.

Some pregnant people wear compression stockings to give them a little extra support, especially if they spend a lot of time on their feet. Compression stockings are also helpful in reducing the risk of blood clots in the legs.

Movement can also help. Immobility can be a risk factor for blood clotting, so a doctor may also encourage you to remain active. A doctor might also urge you to get up to walk as soon as possible after delivery, especially if you deliver by C-section.

If you already know you have thrombophilia and are pregnant, it is important to speak with a doctor. They can help you decide the best way to manage your condition and lower your risk during pregnancy and after delivery.

You should also consider speaking with a doctor if:

  • you have a family history of thrombophilia
  • you’ve recently been seriously injured
  • you’ve been or are currently being treated for cancer
  • you’ve spent significant time on bed rest

Even if you don’t have a history of blood clots, you might want to discuss your risk profile with a doctor if you are planning to become pregnant.

Pregnancy is a major risk factor for blood clots, especially blood clots in the veins. A doctor can help you learn more about your risk for thrombophilia in pregnancy and understand the symptoms to watch out for so you can seek medical care if needed.