Objective To determine reasons for cesarean and medically indicated deliveries in a registry of pregnant women with SLE compared to RA. Methods Pregnant women with SLE or RA were prospectively followed, and pregnancy outcomes were collected, including whether labor was spontaneous or medically indicated and delivery was vaginal or cesarean. Preterm birth was defined as a birth <37 weeks gestation. Differences in reasons for cesarean delivery and indication of delivery between term and preterm births were determined by Fisher's exact test. Results Compared to RA pregnancies, SLE pregnancies had modestly higher rates of preterm birth (24% SLE vs 14% RA), pre-eclampsia (15% SLE vs 7% RA), and cesarean delivery (48% SLE vs 30% RA). The majority of preterm births among women with SLE were indicated (70%), most commonly for pre-eclampsia or the health of the infant or mother. The majority of preterm births among women with RA, however, were spontaneous, primarily due to premature rupture of membranes. Conclusion Pre-eclampsia and maternal SLE activity appear to be the key drivers for the high rate of preterm birth and medically indicated delivery in SLE. This contrasts with RA, where preterm labor is most often due to spontaneous onset of labor.
Keywords: cesarean delivery; medically indicated delivery; pregnancy; preterm birth; rheumatoid arthritis; systemic lupus erythematosus.