BOSTON — Successful pregnancies in women with systemic lupus erythematosus depend on a combination of factors, including disease activity at the time of conception, maternal renal function, the presence of lupus-related autoantibodies, and medication use, according to Dr. Lisa Sammaritano of Cornell University, Ithaca, N.Y.
In terms of disease activity, “it has been shown time and again that patients with inactive disease for 6 or more months prior to conception have a substantially reduced risk of experiencing a disease flare during pregnancy than women with active disease,” Dr. Sammaritano reported at a meeting on rheumatology sponsored by Harvard Medical School. “[Physicians] should have this in mind during prepregnancy consultations and advise patients to wait for periods of stable disease before trying to conceive.”
Maternal renal function should also be evaluated prior to conception, said Dr. Sammaritano. In women with renal insufficiency, pregnancy can accelerate a decline in renal function and worsen hypertension and proteinuria, thus increasing the risk of maternal and fetal complications, such as preeclampsia, intrauterine growth restriction, and intrauterine death.
Additionally, “it's essential to assess renal function before pregnancy in women with renal insufficiency in order to better differentiate worsening lupus-related renal disease from superimposed preeclampsia during pregnancy,” Dr. Sammaritano said. Kidney problems during pregnancy are more likely to be related to systemic lupus erythematosus (SLE) renal disease than to preeclampsia if the patient exhibits clinical symptoms of active SLE, has an elevated anti-double-stranded DNA antibody, or has detectable red blood cell casts in the urine, she said.
The presence and levels of certain lupus-related autoantibodies can also affect pregnancy outcome, Dr. Sammaritano noted. The antiphospholipid antibodies as well as lupus anticoagulant and medium to high anticardiolipin antibodies have been associated with recurrent pregnancy losses, poor fetal growth, preeclampsia, and stillbirths in women with lupus. Identifying the antibodies ahead of time “is critical, because studies have shown that treatment with medication, such as aspirin or heparin, during pregnancy can improve the viability of the fetus,” she added.
Two other lupus-related autoantibodies—anti-SS-A and anti-SS-B—can have an effect on the babies born to mothers with lupus. The presence of one or both of these IgG autoantibodies in the mother increases the risk of neonatal lupus erythematosus (NLE), which can cause rash or changes in blood counts or liver function and, in severe cases, can affect the conduction system of the heart, Dr. Sammaritano said.
For pregnant women who test positive for anti-SS-A or anti-SS-B, current management guidelines recommend weekly fetal echocardiographic monitoring between gestational weeks 16 and 26 and biweekly monitoring between weeks 27 and 34 to look for congenital heart block, she said.
In terms of medication during pregnancy for women with lupus, corticosteroids should be used for active disease only.
“If a patient is on a dose of steroid, in general we will continue at a low dose during the course of the pregnancy. However, we do not recommend prophylactic steroids in patients without active disease in an effort to prevent a flare,” Dr. Sammaritano said.