Prevalence of various antiphospholipid antibodies in pregnant women

Antiphospholipid antibodies (APAs) are characterized as a heterogeneous pop ulation of autoantibodies directed against different target antigens, predo minantly anionic phospholipids or phospholipid-containing structures. The p resence of APAs has been strongly associated with a variety of clinical dis orders including adverse pregnancy complications such as spontaneous aborti ons, pregnancy-induced hypertension, preeclampsia and intrauterine growth r etardation. The purpose of this study was to compare the prevalence of anti cardiolipin antibodies (ACAs), which are routinely examined, with APAs dire cted against phosphatidylserine (APS), phosphatidylinositol (API), phosphat idylethanolamine (APE) and phosphatidylcholine (APC) in the sera of pregnan t women. We examined 410 serum samples of pregnant women hospitalized in th e department for pathological pregnancies. They underwent prenatal biochemi cal screening of fetal congenital abnormalities in the first and the second trimester of gravidity. Anticardiolipin IgG and IgM were measured using co mmercial ELISA kits (ImmuLisa(TM) Anti-Cardiolipin Antibody), whereas APS, APE, API and APC were determined by our modified ELISA kit. Among 410 pregn ant women we found 21 patients (5.1 %) positive for ACA IgG (>20 GPL) and 3 0 patients (7.3 %) positive for ACA IgM (>10 MPL). It was found that 7.8 % of pregnant women had at least one high-titer APA Ige and 9.8 % high-titer APA IgM. One third of ACA IgG or IgM positive sera contained polyspecific a utoantibodies reactive to at least two various phospholipids. In the group of IgG ACA positive women, 28.6 % patients were positive for APS, 28.6 % we re positive or moderately positive for API, 23.8 % for APC and 19 % for APE . In the group of IgM ACA positive women, 33.3 % were also positive for APS , 26.7 % for APE, 26.7 % for API and 23.3 % for APC were present. IgG and I gM ACA negative patients exhibited a significantly lower incidence of other APA than the group of ACA positive pregnant women. It still remains to cla rify if the routine examination of APA reacting with other anionic and zwit terionic antigens other than cardiolipin would improve the probability of i dentifying women liable to adverse pregnancy complications.