Objective: To summarize the maternal/fetal outcome of pregnancy in antiphospholipid syndrome (APS) patients to evaluate the influence of treatment on the outcomes of pregnancy, and to investigate the possible clinical predictors of unsuccessful pregnancy.

Methods: The clinical characteristics, laboratory profiles and the outcomes of delivery of 54 APS patients from January 2000 to March 2013 were investigated retrospectively.

Results: (1) Maternal/fetal outcome: 17 pregnancies (31.4%) resulted in full term delivery, 7 (12.9%) in stillbirth, 16 (29.6%) in spontaneous abortion,10 (18.5%) in premature birth due to eclampsia or severe preeclampsia or signs of placental insufficiency, 4 (7.4%)received therapeutic termination of pregnancy due to eclampsia or severe preeclampsia. In 27 live birth cases, 8 (29.6%) were fetal growth restriction, 4 (14.8%) were low birth weight infants, and 3 (11.1%) were very low birth weight infants. (2) Influence of treatment on the pregnancy outcomes and complications: 24 APS patients were given the treatment of aspirin or aspirin combined with low molecular weight heparin, and 30 patients received no treatment. Compared with the untreated group, the treated group had lower rate of fetal loss, higher rate of full-term delivery, increased gestational age and birth weight, decreased incidence of preeclampsia / eclampsia and thrombocytopenia. There was a significant difference between the two groups (P<0.05). (3)Possible risk factors of unsuccessful pregnancy: there were 17 successful pregnancies and 37 unsuccessful pregnancy. The rate of double APL positive and antibody titers ≥ three times the upper limit of normal were higher in the unsuccessful pregnancy group than the successful pregnancy group. Antibody negative rate before pregnancy proportion of patients received treatment and the level of complement 4 were lower in the unsuccessful pregnancy group.

Conclusion: Pregnant women with APS are an extremely high risk group for adverse maternal /fetal outcome. Treatments can improve the pregnancy outcome of the APS patients. APL not turning negative before pregnancy double APL positive, antibody titers ≥ three times the upper limit of normal and complement 4 decrease may be the risk factors for pregnancy failure and treatment may be a protective factor for successful pregnancy.