Aims: To investigate the outcome of pregnancy complicated with Systemic lupus erythematosus (SLE) and its correlative factors and try to provide the best chance for conception,pregnant monitoring to prevent the deterioration of SLE and pregnancy loss and improve the perinatal quality.Materials and Methods: Retrospective study,from December,1995 to July,2011,249 pregnancies in 243 females with SLE in Renji Hospital Affiliated to Shanghai Jiao Tong University School of Medicine To investigate the outcome of pregnancy complicated with SLE and its correlative factors.Statistical calculations were performed with SPSS version 19.0.A p-value <0.05 was considered significant.Results: The mean patient age was 28.1 ±4.2(range 20~47,median 28).Mean numbers of pregnancies per patient were 1.1 ± 1.3(range 0~7,median 1).The mean gestation age was 37.2± 2.2 weeks (range 28+6-41 +3).Except for 12 cases of family planning,185 of the 237 pregnancies occurred in the period of disease remission at the time of conception,33 occurred during the pregnancy,35 complicated hypertensive disorders during pregnancy.Except for 59 cases of pregnancy loss,the mean birth weight was 2766.4 ± 574.8g.There were 58 cases(32.2%) preterm deliveries and 33 cases(18.3%) small for gestational age in this study,Apgar scores 1-9.6 ± 1.4,5-9.8 ± 0.9.The Active disease at conception,proteinuria>2g/d,the presence of antinuclear antibody (ANA) and the low level of C3 were found related to the pregnancy loss.The lupus nephritis,proteinuria>1g/d and the low level of CH50 were associated with preterm delivery.The Active disease at conception and the diagnosis of SLE during the pregnancy were associated with IUGR.The Active disease at conception,the lupus nephritis,proteinuria>1g/d and the low level of C3 were related to PIH.The presence of RNP,proteinuria>1g/d and the low level of C3 were related to less gestational age at delivery.The presence of RNP,proteinuria>1g/d,the low level of complement (CH50,C3 and C4) and the lack of aspirin were related to lower neonatal birth weight.Conclusions: Although pregnancy in women with SLE is more likely to suffer pregnancy loss and flare-up of SLE,it is relatively safe especially when the lupus nephritis doesn t exist and the pregnancy occurred in the period of disease remission.Therefore,supervision of pregnancy in patients with SLE before and during pregnancy should be conducted by both obstetrician and rheumatologist.The timely and reasonable medication controls the SLE disease and improves the pregnancy outcome.