Embryofetoscopy is an endoscopic technique that enables direct visualization and morphologic study of embryos during the first trimester and allows a selective tissue sample to be obtained. We describe an early missed abortion in the first trimester, apparently without cause according to findings at ultrasound. Embryofetoscopy revealed a remarkable dorsal cystic formation covered by a blood clot in the thoracolumbar region of the spine, suggestive of meningocele or myelomeningocele. A selective tissue biopsy specimen of the cystic lesion demonstrated meningeal tissue such as a meningocele. Embryofetoscopy in missed abortion could provide information about the causes of severe defects in embryo development so that parents can be effectively advised insofar as future pregnancies.