Twenty years ago, women with Lupus were counseled not to become pregnant because of the risk of a flare of the disease and an increased risk of miscarriage. Experts disagree on the exact numbers, but approximately 20-25 percent of Lupus pregnancies end in miscarriage, compared with 10-15 percent of pregnancies in women without the disease. Pregnancy counseling and planning before pregnancy is important. Optimally, a woman should have no signs or symptoms of Lupus before she becomes pregnant.
Researchers have now identified two closely related Lupus autoantibodies, anticardiolipin antibody and Lupus anticoagulant, that are associated with risk of miscarriage. One-third to one-half of women with Lupus have these autoantibodies, which can be detected by blood test. Identifying women with the autoantibodies early in the pregnancy may help physicians take steps to reduce the risk of miscarriage. Pregnant women who test positive for these autoantibodies and who have had previous miscarriages are generally treated with baby aspirin or heparin throughout their pregnancy.
Some women may experience a mild to moderate flare during or after their pregnancy; others may not. Pregnant women with Lupus, especially those taking corticosteroids, are also likely to develop pregnancy-induced hypertension, diabetes, hyperglycemia, and kidney complications. About 25 percent of babies of women with Lupus are born prematurely, but do not suffer from birth defects.
About 3 percent of babies born to mothers with SLE will have neonatal Lupus, or specific antibodies called anti-Ro(SSA) and anti-La(SSB). This is not the same as SLE and is almost always temporary. The syndrome is thought to be caused by passive transfer of anti-Ro antibodies from the mother to the fetus. About one-third of women with SLE have this antibody. By 3-6 months of age, the rash and blood abnormalities associated with neonatal Lupus disappear. Very rarely, babies with neonatal Lupus will have a congenital complete heart block. This problem is permanent, but can be treated with a pacemaker.