[Prenatal diagnosis of thanatophoric dysplasia at 21st week of pregnancy].

We report making the prenatal diagnosis of thanatophoric dysplasia without "cloverleaf" skull at 21 weeks gestation. The ultrasound examination showed short and bowed limbs, narrow thorax, and large head. Radiological and histological studies confirmed the aborted fetus to be affected with thanatophoric dysplasia. The differential prenatal diagnosis with other skeletal dysplasias is discussed.