The structure of antiphospholipid antibodies circulation investigated in pregnancy І and ІІ trimester

Abstract

The article presents the results of a prospective study on the presence of antiphospholipid antibodies in healthy primagravida with the analysis of further gestational complications. The objective: to determine the serum circulation of antibodies to different types of phospholipids in the first and second gestational trimester and to study the incidence of obstetric complications depending on this circulation. Materials and methods. Determination of antibodies to phospholipids in 11–12 and 18–20 gestational weeks by immunoassay analysis. The study included 150 primagravida (11-12 weeks) without reproductive impairment in history, a re-study was performed in 148 women, since 2 cases of spontaneus abortion were observed. The relative risk of development of major obstetric complications in women with the appearance of antibodies to phospholipids in the second trimester of pregnancy is calculated. Results. At the first inspection, the frequency of detection of antibodies to phospholipids ranged from 3 to 4%, which corresponds to global data on the prevalence of antibody circulation in a healthy population. However, in 18-20 weeks, a statistically significant increase in the frequency of antibody circulation, mainly to phosphatidylserine (21.6%) and phosphatidylethanolamine (17.4%), was detected. The peculiarities of the structure of the cell membrane are asymmetry of the location of phospholipids, in which negatively charged molecules, including phosphatidylserine and phosphotadylethanolamine, are located dominantly in a inner layer. The emergence of antibodies precisely to these molecules in the dynamics of pregnancy is evidence of their externalization, which may be the result of a violation of the normal functioning of the endothelium. Analysis of the course of the second half of pregnancy in patients with detected antibody subtypes showed an increase in the relative risk of severe preeclampsia, placental dysfunction and premature labor. Conclusions: 1. The APA circulation frequency by healthy primagravida in first gestational trimester is in accordance to world population. 2. In the second trimester an increasing of APA detection is registered, exactly for phosphatidylserin (21.6%) and phosphatidyletanolamin (17.4%) antibodies 3. Appearance of antibodies to negative phospholipids in the second pregnancy trimester lets propose destabilization of endothelium membranes in these patients, what is confirmed by a higher frequency of main obstetrics complications prospectively. Key words: antibodies to phospholipids, phosphatidylserine antibodies, phosphatidylethanolamine antibodies, endothelial dysfunction.