A twenty-three years old woman, without previous heart disease developed endocarditis with negative bloods cultures on the fourth month of her third pregnancy. Fever was controlled through antibiotics, however she developed cardiac insufficiency and was submitted to surgery for replacement of aortic valve with a bioprosthesis. The post operative period showed no problems and the patient was discharged on the forty second day after admission. On the thirty ninth week of pregnancy she gave cesarean birth, without complications. The newly born, apgar 5 (1 min.) and 7 (5 min) presented signs of neurological problems, characterized on the second month as a cerebral atrophy. Among various possible factors, the most likely would be cardiopulmonary bypass circulation as the cause of the neurological malformation.