Prenatal diagnosis of a severe deforming type of osteogenesis imperfecta.

A pregnancy at risk for a severe deforming type of osteogenesis imperfecta (OI) was monitored by ultrasonography and radiography. Long bone measurements were normal at 15 1/2 weeks gestation, but ultrasound detected an abnormality of one femur that appeared to be a fracture. The ultrasound study at 19 weeks revealed severe shortness of the femora, and radiographs showed only vertebral bodies with no other fetal skeletal parts clearly visible. These studies indicate the feasibility of prenatal diagnosis before 20 weeks for the more severe handicapping types of OI that are compatible with survival past the newborn period and that can result in death during later infancy.