Date Updated: 11/04/2022

Atrial fibrillation (A-fib) is a common heart rhythm disorder (arrhythmia). If you have A-fib, you might need to change how you manage the condition during your pregnancy. For instance, you might need to avoid certain medications while you are pregnant.

Atrial fibrillation increases the risk of blood clots in the heart. Pregnancy increases the risk of blood clots in the legs. Taking blood-thinning drugs (anticoagulants) can help reduce these risks. But some blood thinners may not be safe to take during pregnancy.

If possible, discuss your condition and medications with a health care provider before you become pregnant. Pregnancy can make atrial fibrillation worse. It's also possible to develop it while you're pregnant. Talk to your provider to create the safest treatment plan for you and your developing baby.

Blood-thinning drugs to avoid during pregnancy

The blood-thinning drug warfarin (Jantoven) is not recommended during pregnancy. If you take it, your provider might switch you to a different blood thinner during all or part of your pregnancy. Warfarin may be associated with pregnancy risks.

Other blood thinners taken by mouth (direct-acting oral anticoagulants) are not recommended during pregnancy. These drugs include dabigatran (Pradaxa), rivaroxaban (Xarelto) and apixaban (Eliquis). There aren't enough studies to determine their effects and safety during pregnancy.

Blood thinners during pregnancy, labor and delivery

Studies show that the blood-thinner heparin is safe to take during pregnancy. Some pregnant women with atrial fibrillation get heparin shots to prevent blood clots.

Even when taking a blood thinner, you're still at risk of developing blood clots during pregnancy. Watch for symptoms of blood clots, such as chest pain, shortness of breath, leg swelling or warnings of stroke, including changes in vision, trouble speaking and numbness in the face, arms or legs. Contact your health care provider immediately if you notice unusual symptoms.

Heparin and other blood-thinning drugs increase the risk of major bleeding. If you have any bleeding, tell your provider. Blood thinners are usually stopped during labor and delivery, unless you're at very high risk of blood clots.

Blood thinners after delivery

You can usually start taking your blood-thinning medication again after your child is born. Your provider will give you specific instructions. Some blood thinners might not be recommended while breastfeeding. Together, you and your care providers can determine which blood thinner is safe for you and your baby.

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