I have an autoimmune disorder that, over the last 10 years, has caused problems with my thyroid, liver, heart, blood platelets, etc. I have recently started worrying about how this would affect my ability to get pregnant and carry a child full-term. Do you have any thoughts on this?

K.

Autoimmune diseases result from inappropriate production of antibodies that attack normal organs and tissue such as the thyroid, parathyroid, pancreas, ovary, joints, platelets and the placenta. They can also attack blood vessels and cause inflammation of veins and arteries, which can lead to inappropriate blood clotting (thrombosis). Lupus, idiopathic thrombocytopenia, and Graves' disease (a form of thyroid disorder) are just a few of the more common autoimmune conditions. No one is certain why these conditions develop, nor is there an obvious cure. Newer antiinflammatory agents can help suppress the immune system's attack and the resulting symptoms. If a hormone-producing organ is damaged, replacement hormones may be necessary; this is the case with diabetes (treated with supplements of insulin) or hypothyroidism (treated with thyroid hormone).

Antiphospholipid syndrome is often diagnosed in women with abnormal antibodies to blood-vessel wall components such as cardiolipin, serine and ethanolamine who experience an episode of abnormal clotting. This can involve thrombophlebitis (clotted vein) in an extremity, mid-trimester placental infarction (loss of circulation to the placenta and fetal death), or pulmonary embolus (a blood clot in one of the pulmonary vessels).

The role these antibodies play in early recurrent pregnancy loss or infertility is unclear and the data are often conflicting. Still, many physicians will check the immune system for the antiphospholipid antibodies listed in the previous paragraph. They may also test for lupus anticoagulant (if this is present, you are actually at increased risk of abnormal clotting). If any of these are present, physicians may choose to treat with a combination of low-dose baby aspirin and twice-daily heparin injections to prevent abnormal clotting. This therapy is not without risks, and you need to have a detailed discussion with your physician of your own situation, the likely benefit and associated risks.

ANA is often measured to rule out lupus, but the data do not support the use of this test or its many subtests (ssDNA, dsDNA, histones) as having any value in the diagnosis or treatment of infertility. The presence of thyroid antibodies does not directly result in infertility or pregnancy loss. However, if these antibodies have damaged the thyroid and a low thyroid hormone level is present, your fertility may be hampered. In addition, women with a propensity to make one inappropriate antibody, may in fact make others.

While the presence of inappropriate antibodies may not directly affect your chances of pregnancy or result in miscarriage, it is best to make sure "all systems are go" and that you are in the best health possible before attempting pregnancy.