[Prenatal diagnosis of thanatophoric dysplasia at the 20th week of pregnancy using ultrasonography].

We report on prenatal diagnosis of a fetus with thanatophoric dysplasia type 1 at 20 weeks gestation. The ultrasonographic examination showed shortened bowed limbs, narrow chest, relatively large head, protuberant abdomen, and hydramnios. Radiological and histological studies confirmed the aborted fetus had thanatophoric dysplasia. The differential prenatal diagnosis with other skeletal dysplasia is discussed.