Systemic lupus erythematosus is a hormone-dependent disorder predominantly affecting young women in whom changes in hormonal activity affect the course of the disease. More specifically, pregnancy is associated in 50 to 60% of cases with a clinical flare manifesting as renal or hematological symptoms, usualy during the second or third trimester but occasionally in the postpartal period. Patients should be strongly advised to start a pregnancy only if their disease has been stable for at least 6 months, and they should be informed of the few contraindications. Severe flares are uncommon (10%) and the risk of maternal death is now 2 to 3%. The risk of the fetus remains high, however. Thus, fetal loss is common, particularly in patients with a lupus anticoagulant, renal failure, or arterial hypertension. Preterm birth occurs in 25% to 50% of cases and intrauterine growth retardation in 30%. Neonatal lupus with or without congenital heart block is exceedingly rare, being seen in the 1% of SLE women who have anti-SSA (Ro) and/or SSB (La) antibodies. To ensure a favorable outcome for both the mother and the child, the pregnancy should be planned, started during a period of disease stability, monitored closely (physical examination, laboratory tests, and Doppler ultrasound), and treated as needed (with antimalarial therapy throughout the pregnancy). Even with these precautions, however, preterm birth remains common.