Early Detection of Decreased Soluble HLA‐G Levels in the Maternal Circulation Predicts the Occurrence of Preeclampsia and Intrauterine Growth Retardation During Further Course of Pregnancy

Abstract

Soluble (s) HLA-G1/G5 molecules may potentially affect immune homeostasis during pregnancy. The aim of this study was to determine changes of sHLA-G1/G5 plasma levels throughout normal pregnancy and to assess its predictive value for the occurrence of characteristic gestation-associated diseases during further course of pregnancy. sHLA-G1/G5 levels were estimated in plasma samples of 40 non-pregnant women, 291 women throughout normal pregnancy and 236 women affected by different complications. In comparison with non-pregnant women sHLA-G1/G5 levels strongly increased during the first trimenon and then decreased continuously toward term. Non-parametric discriminant analysis showed that women with significantly decreased sHLA-G1/G5 levels in the second trimenon had an increased risk of developing preeclampsia and/or intrauterine growth retardation (IUGR) during further course of pregnancy. However, in the third trimenon, sHLA-G1/G5 levels in affected women did not deviate significantly from those of non-affected women. Surprisingly, significantly increased sHLA-G1/G5 levels were detected in third trimenon women with uncontrollable preterm labor, but not in women with prolonged preterm rupture of fetal membranes. For the identification of women with an increased risk of IUGR and/or preeclampsia, measurement of sHLA-G1/G5 plasma levels may be a powerful new tool in prenatal diagnostics.