462: High antiphospholipid antibody titers are associated with adverse pregnancy outcome in women with antiphospholipid antibody syndrome

Abstract

S 62 HIGH ANTIPHOSPHOLIPID ANTIBODY TITERS ARE ASSOCIATED WITH ADVE PREGNANCY OUTCOME IN WOMEN WITH ANTIPHOSPHOLIPID ANTIBO SYNDROME MICHAL J. SIMCHEN, RACHEL PAUZNER, GUY ROFE, EYAL SCHIFF, MORDECHAI DULITZKI, Sheba Medical Center, Tel Aviv University, Obstetrics and Gynecology, Ramat Gan, Israel, Sheba Medical Center, Tel Aviv University, Internal Medicine, Rheumatology, Ramat Gan, Israel, Sheba Medical Center, Tel-Aviv University, Ramat Gan, Israel OBJECTIVE: To investigate whether, in patients with antiphospholipid antibody syndrome (APS), high antibody titers predict adverse pregnancy outcome. STUDY DESIGN: Women diagnosed with APS according to strict clinical and laboratory criteria were prospectively followed in pregnancy. Lupus anticoagulant, anticardiolipin antibodies and Beta-2 Glycoprotein 1 levels were measured prior to pregnancy. Women with antibody titers more than 4 times upper limit of normal were termed High Titer (HT) group, while women with lower positive antibody titers were considered Low Titer (LT) group. All women were treated with LMWH 0.7-1 mg/kg/day and aspirin 100 mg daily. Adverse pregnancy outcomes included fetal/neonatal loss, significantly premature birth 32 weeks= gestation, and intrauterine growth restriction (IUGR, 10th percentile). RESULTS: 51 women in 55 pregnancies were prospectively followed, 20 in the HT and 35 in the LT groups. 35% of HT women and 11.4% of LT women had triple antibody positivity (p 0.07). The risks of pregnancy loss, delivery 32 weeks and/or IUGR were all significantly more common in the HT as compared with the LT group. Moreover, among women with high titers, only 35% of pregnancies culminated in appropriately grown, liveborn infants 32 wks gestation, as compared with 77% of pregnancies with low titers (OR 0.17, 95% CI 0.05-0.53). The 2 groups were similar in the proportion of previous pregnancy losses, previous thromboembolic events, primary/secondary APS and concurrent genetic thrombophilias. CONCLUSION: In women with antiphospholipid syndrome, high antibody titers prior to pregnancy define a unique and extremely high-risk group for adverse pregnancy outcome. These women need special prenatal consultation and tight prenatal care.