Female, 5 years old; first pregnancy of term, eutocic, weight 3,100 g; breast fed, complete vaccination program. A bronchial pathology that was present seven months later, yielded with medical treatment. Her illness started on September, 1984 after sever trauma by horse kick, presenting with a tumor in left illiac fossa; there was pain, improved by analgesics; the tumor continued to grow up to 5 x 6 cm in diameter, painful on palpation, causing hospital admission. Thirty days later an ultrasonographic study reported an ovoid echogenic and echolucid mass of 6.5 cm in left ovary; an infra-umbilical laparotomy was performed, finding a left ovarian tumarration, ovoid, pink white, with vascular areas, 24 x 18 x 15 cm at maximal diameters, solid, smooth and bright; at section there was gray-white, nodular tissue, with cystic cavities, 0.5 cm. Electronic microscopy an immunochemistry study were carried out in order to confirm the diagnosis of juvenile granulosa cell tumor. The patient died seven months later.