Are You at Risk for Dangerous Blood Clotting During Pregnancy?

Antiphospholipid syndrome is rare but dangerous
Antiphospholipid Syndrome: Are You at Risk During Pregnancy?

By: Howard Smith, MD

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Women with antiphospholipid syndrome (APS), a rare autoimmune disease that affects how the blood clots, face greater risks when they’re pregnant. However, there are treatments that can help reduce the risks for both mother and baby.

If you have APS, it’s best to talk to your rheumatologist or an obstetrician who has expertise in high-risk pregnancies before you get pregnant.

Here’s what you need to know about APS and your pregnancy.

What are the risks?

Pregnant women with APS have an increased risk of developing blood clots and of having a miscarriage or stillbirth. There are risks of other pregnancy-related complications, including preeclampsia (high blood pressure), early delivery and low blood flow to the fetus.

What can help reduce the risks?

Your doctor may need to start or stop some treatment options before you become pregnant and during pregnancy.

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When you’re pregnant, you should meet regularly with your rheumatologist and obstetrician. They can adjust your care as needed.

Your doctors will base your treatment on your history of blood clots, current level of antibodies and prior pregnancy complications. The most common treatment options for women prior to and during pregnancy are:

  • Low-dose aspirin: Typically used with other treatments, your doctor may suggest that you start taking this before you try to get pregnant.  Usually, you’ll stop taking the aspirin around the third month of your pregnancy and then begin again after you deliver.
  • Heparin: Treatment usually starts after you are pregnant and stops when labor begins. You may resume heparin for up to two months after delivery. There are two types of heparin. One requires a twice-daily injection. The other requires an injection only once per day.

Warfarin is another treatment, but can cause birth defects if you take it during pregnancy. Because of risks to the fetus, this treatment is more commonly used after delivery. Typically, your doctor will recommend stopping warfarin treatment six weeks before you become pregnant. Your doctor may restart it after 14 weeks of pregnancy, but he or she will need to stop it again by your 36th week.

What causes APS?

Your body protects against harmful “invaders” with antibodies, but in some cases, it produces antibodies that mistakenly attack healthy tissue.

This is what happens with antiphospholipid antibodies, which can attack the proteins that bind phospholipids. Phospholipids are found throughout our bodies. They play a critical role in helping blood to clot properly.

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These antiphospholipid antibodies can lead to APS, although you can have the antibodies and not have any symptoms. The signs of APS are blood clots in your veins or arteries and repeated pregnancy complications. It’s more common in women, and in those who have other autoimmune or rheumatic diseases, such as lupus.

Should I be tested for APS?

If you have a history of blood clots or have had more than one miscarriage, you should talk to your doctor or obstetrician to find out if APS might be a possible cause.

If you haven’t had a previous miscarriage or blood clot, testing isn’t recommended. There are often false-positive test results for these types of antibodies and treatment typically isn’t indicated.

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