Atrial fibrillation is a common type of irregular heartbeat, also called an arrhythmia. The condition is commonly called AFib. If you have AFib, you might need to change how you manage it during pregnancy. For instance, you might be told not to take some medicines while you’re pregnant.

Atrial fibrillation increases the risk of blood clots in the heart. Pregnancy increases the risk of blood clots in the legs. Taking blood thinners, also called anticoagulants, can help reduce these risks. But some blood thinners may not be safe to take during pregnancy. If possible, tell your healthcare team about all the medicines you take before you become pregnant.

Pregnancy can make AFib worse. Also, it’s possible to develop the irregular heartbeat while you’re pregnant. Talk to your health care team to create the safest treatment plan for you and your growing baby.

Blood-thinning medicines to avoid during pregnancy

Do not take the blood thinner warfarin (Jantoven) during pregnancy. If you need a blood thinner, your healthcare team may switch you to a different one during all or part of your pregnancy.

Blood thinners called direct oral-acting anticoagulants, also called DOACs, are not recommended during pregnancy. There aren’t enough studies to tell if the medicines are safe to take during pregnancy.

DOACs include:

• Dabigatran (Pradaxa).
• Rivaroxaban (Xarelto).
• Edoxaban (Savaysa).
• Apixaban (Eliquis).

Blood thinners during pregnancy, labor and delivery

Studies show that some blood thinners do not cross the placenta. These include heparin and low molecular weight heparin, such as enoxaparin (Lovenox). They can be used during pregnancy when monitored closely. Some pregnant people with AFib get low molecular weight heparin shots to prevent blood clots.

Even when taking a blood thinner, blood clots may happen during pregnancy. Watch for symptoms of blood clots such as:

• Chest pain.
• Shortness of breath.
• Leg swelling.

Get help right away if you have symptoms of stroke, including:

• Changes in vision.
• Trouble speaking.
• Numbness in the face, arms or legs.

Get medical help right away if you notice any other unusual symptoms.

Heparin and other blood thinners increase the risk of major bleeding. This includes bleeding where the placenta attaches to the uterus. If you have any bleeding, tell your healthcare team. Blood thinners are often 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 medicine again after your baby is born. Your healthcare team gives you specific instructions. Some blood thinners might not be recommended while breastfeeding. Together, you and your care team can decide which blood thinner is safe for you and your baby.