Multiparametric Assessment of Maternal Vascular Function in the Prediction of Hypertensive Disorders of Pregnancy

Primary aim: To determine the role of the combination of arterial tonometry and endothelial glycocalyx measurement in predicting the risk of developing hypertensive disorders in pregnancy. Secondary aims: * To determine the association between circulating markers of angiogenesis and endothelial dysfunction (ANG-1, ANG-2, ET-1, ICAM-1 and VCAM-1) and the development of hypertensive disorders of pregnancy. * To define the trends of serum uric acid, lipids and xanthine oxidase activity in normotensive and hypertensive pregnancies. * To determine the ability of the combination of arterial tonometry and endothelial glycocalyx measurement, performed in the two study visits during pregnancy, in predicting the risk of long-term maternal cardiovascular disease.