Prenatal diagnosis and obstetric management of thanatophoric dwarfism.

Prenatal diagnosis of Thanatophoric Dwarfism by ultrasonography was made at 36 weeks in a pregnancy complicated by polyhydramnios. The diagnosis was based on the evidence of extremely short and deformed limbs, a narrow thorax relative to the abdomen and a degree of hydrocephalus. Progressive hydrocephalus as evidenced by repeated ultrasonography influenced subsequent obstetric management in this patient. Since polyhydramnios is commonly associated with fetal skeletal dysplasia, scanning of limb lengths and limb abnormalities should therefore be an essential part of a obstetric ultrasound examination when this complication is suspected.