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.

Metabolomics involves a new technology using the methods of separation and detection complex to investigate a set of 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 detect metabolic fingerprints that can be particularly useful for identifying new biomarkers. These will thereafter be quantified and validated by metabolic profiling. To our knowledge, there are few studies on metabolomics and pregnancy.

Methods:

The studied population will be women hospitalized for preeclampsia (after 20 SA). Women in the control group will be matched to women hospitalized for pre-eclampsia according to gestational age at diagnosis of pre-eclampsia, maternal age, parity, ethnicity and body mass index.

Blood and urine samples will be taken:

Case control:

• Following the diagnosis of preeclampsia
• At each blood test requested by the physician during the follow-up
• When the patient will be in labor (cervix ripening > 5 cm) or before the caesarean section
• 48 hours after delivery
• 6-8 weeks after delivery

Control group:

• Following the inclusion as a control in the study
• At admission for delivery
• When the patient will be in labor (dilation > 5 cm) or before the caesarean section
• 48 hours after delivery
• 6-8 weeks after delivery

Inclusion Criteria:

• Case group: Women hospitalized for pre-eclampsia after 20 0/7 weeks of gestation. The diagnosis of preeclampsia include a combination of the following criteria: after 20 weeks of pregnancy in a previously normotensive woman, a diastolic blood pressure ≥ 90 mmHg recorded twice at least four hours apart or ≥ 110 mmHg, with proteinuria ≥ 300 mg/24h or ≥ 30 mg / mmol protein / urinary creatinine in a urine sample or factor (s) serious maternal / fetal (according to consensus SOGC).
• Control group: Women will be matched to women with preeclampsia according to gestational age at diagnosis of pre-eclampsia, maternal age (in stratum of 5 years), gender, ethnicity (4 categories: Caucasian, black, Asian and other) and body mass index (5 classes: < 20, 20-25, 26-30, 31-35 and < 35). Patients of this group should be at low risk of obstetric complications at recruitment and planning to deliver at the CHUS.

Exclusion Criteria:

- Minor patients, patients with post-partum preeclampsia, premature rupture of membranes, a severe congenital fetal malformation, twin pregnancies and fetal death. Patients with underlying diseases taht could be associated with preeclampsia as pre-existing hypertension (ie before 20SA), anti-phospholipid syndrome, lupus, type DM 1-2, nephropathy, etc will be excluded. Patients who have a complication during the pregnancy will be excluded from the control group.

women who deliver at the CHUS