Dissection of the aorta is a serious condition but rare in young women, and occurring during the 3rd trimester of pregnancy. The main risk factors are hypertension and diseases of the connective tissue or of collagen (Marfan's syndrome and Ehlers-Danlos disease). The authors report a case of dissection of the aorta managed in a pluridisciplinary manner by the anaesthetists, cardiologists, obstetricians and cardiothoracic surgeons, which resulted in a favourable outcome for both mother and baby. The diagnosis of Ehlers-Danlos disease was made from the onset and, over a period of 10 years with CT scan and annual echocardiographic follow-up, total replacement of the supra-coronary aorta was performed in several stages.