RESUMEN
Two cases of spontaneous delivery at 27 weeks and 38 weeks are reported in two patients with Eisenmenger's syndrome. One case did not present any problems, while the other was followed by maternal death on the 6th day post-partum. The cause of death was similar to that of other cases reported in the literature. The pathophysiological explanation of the terminal clinical condition with refractory hypoxia remains unclear. In view of the maternal mortality of about 50 per cent, these patients should be prescribed effective contraception, free of thrombogenic and infectious risks. The therapeutic approach in patients who become pregnant is not well defined. However, a number of principles should be observed during delivery: oxygen therapy, rapid correction of haemorrhages, the timing and the modalities of anti-coagulation are controversial. The failure of the usual methods of resuscitation in the terminal stage raises the possibility of using fibrinolytics.