Autoimmune Disorders During Pregnancy

ByLara A. Friel, MD, PhD, University of Texas Health Medical School at Houston, McGovern Medical School
Reviewed/Revised Nov 2023
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Autoimmune disorders, including Graves disease, are more common among women, particularly pregnant women. The abnormal antibodies produced in autoimmune disorders can cross the placenta and cause problems in the fetus. Pregnancy affects different autoimmune disorders in different ways.

Antiphospholipid Syndrome

Antiphospholipid syndrome, which causes blood clots to form too easily or excessively, can cause the following during pregnancy:

To diagnose antiphospholipid syndrome, doctors

  • Ask about any unexplained stillbirths or miscarriages, premature births, or problems with blood clots

  • Do blood tests to detect antiphospholipid antibodies on at least two separate occasions

Based on this information, doctors can diagnose antiphospholipid syndrome.

Immune Thrombocytopenia (ITP)

In immune thrombocytopenia, antibodies decrease the number of platelets (also called thrombocytes) in the bloodstream. Platelets are cell-like particles that help in the clotting process. Too few platelets (thrombocytopenia) can cause excessive bleeding in pregnant women and their babies.

If not treated during pregnancy, immune thrombocytopenia tends to become more severe.

The antibodies that cause the disorder may cross the placenta to the fetus. However, they rarely affect the platelet count in the fetus.

The fetus can usually be delivered vaginally.

Treatment of Immune Thrombocytopenia

  • Corticosteroids

  • Sometimes immune globulin, given intravenously

Women who have a dangerously low platelet count may be given high doses of immune globulin intravenously shortly before delivery. Immune globulin (antibodies obtained from the blood of people with a normal immune system) temporarily increases the platelet count and improves blood clotting. As a result, labor can proceed safely, and women can have a vaginal delivery without uncontrolled bleeding.

Pregnant women are given platelet transfusions only when the platelet count is so low that severe bleeding may occur or sometimes when cesarean delivery is needed.

Rarely, when the platelet count remains dangerously low despite treatment, doctors remove the spleen, which normally traps and destroys old blood cells and platelets. The best time for this surgery is during the 2nd trimester.

Myasthenia Gravis

Myasthenia gravis

Some medications that are commonly used during pregnancy, such as magnesium, can make the weakness caused by myasthenia gravis worse. So women who have myasthenia gravis must make sure their doctors know they have it.

Very rarely during labor, women who have myasthenia gravis need help with breathing (assisted ventilation). Although vaginal delivery is recommended, women may require assistance, for example, with forceps.

The antibodies that cause this disorder can cross the placenta. Approximately one of five babies born to women with myasthenia gravis is born with the disorder. However, the resulting muscle weakness in the baby is usually temporary because the antibodies from the mother gradually disappear and the baby does not produce antibodies of this type.

Rheumatoid Arthritis

Rheumatoid arthritis may develop during pregnancy or, even more often, shortly after delivery. If rheumatoid arthritis is present before pregnancy, it may temporarily subside during pregnancy.

This disorder does not affect the fetus directly. However, if arthritis has damaged the hip joints or lower (lumbar) spine, delivery may be difficult for the woman, and cesarean delivery may be needed. The symptoms of rheumatoid arthritis may lessen during pregnancy, but they usually return to their original level after pregnancy.

A flare-up after pregnancy can make it more difficult for women with rheumatoid arthritis to take care of themselves and their infant.

Systemic Lupus Erythematosus (Lupus)

Lupus may appear for the first time, worsen, or become less severe during pregnancy. How a pregnancy affects the course of lupus cannot be predicted, but the most common time for flare-ups is immediately after delivery.

Women who develop lupus often have a history of repeated miscarriages, fetuses that do not grow as much as expected (small for gestational age), and preterm delivery. If women have complications due to lupus (such as kidney damage or high blood pressure), the risk of death for the fetus or newborn and for the woman is increased.

Problems related to lupus can be minimized if the following are done:

  • Women wait to become pregnant until the disorder has been inactive for 6 months.

  • The medications have been adjusted to control lupus as well as possible.

  • Blood pressure and kidney function are normal.

In pregnant women, lupus antibodies may cross the placenta to the fetus. As a result, the fetus may have a very slow heart rate, anemia, a low platelet count, or a low white blood cell count. However, these antibodies gradually disappear over several weeks after the baby is born, and the problems they cause resolve except for the slow heart rate.

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