 The hypertensive disorders of pregnancy are the medical complications more prevalent during pregnancy. In Canada, approximately 1 of pregnancies have complications due to a pre-existing hypertension, 5-6 because of hypertension of pregnancy without proteinuria and 1-2 by preeclampsia. Metabolomics involves a new technology to investigate small molecules that characterize biochemical pathways of interest. The change in concentration levels of these molecules in various biological samples such as urine and blood in the presence of a disease or a patient can be particularly useful for identifying new biomarkers. Our hypothesis is that metabolic patterns in blood and urine of pregnant women who had preeclampsia differ from the metabolomics patterns of patients without preeclampsia.The whole research program has two complementary objectives in order to expect a decrease of prematurity: a better understanding of all the physiological mechanisms leading to prematurity and b better identification of patients at high risk for a better management of these women. 