Haemostasis and Tranexamic Acid in Caesarean Delivery

Inclusion Criteria: * patient randomized into TRAAP2 study (NCT03431805): * adult women admitted for a planned caesarean delivery, * at term ≥ 34 weeks, * haemoglobin level at the last blood sample \>9g/dl, * blood Formula numbering within 7 days before caesarean delivery, informed signed consent) * informed signed consent for BIO-TRAAP Exclusion Criteria: * patient not included into TRAAP2 study: * previous thrombotic event or pre-existing pro-thrombotic disease, * epileptic state or history of seizures, * presence of any chronic or active cardiovascular disease outside hypertension, * any chronic or active renal disease including renal, chronic or acute insufficiency (glomerular flow \<90mL / min), and chronic or active liver disease at risk thrombotic or haemorrhagic, * autoimmune disease, * sickle cell disease, * placenta praevia, * placenta accreta/increta/percreta, * abruption placentae, * eclampsia, * HELLP syndrome, * in utero fetal death, * administration of low-molecular-weight heparin or antiplatelet agents during the week before delivery, * general anaesthesia, * hypersensitivity to tranexamic acid or concentrated hydrochloric acid, instrumental extraction failure, * multiple pregnancy with genital delivery of the first twin and caesarean delivery for the second or at third trimester, * poor understanding of the French language