Midtrimester diagnosis of severe deforming osteogenesis imperfecta with autosomal dominant inheritance

Sonographic examination of a fetus whose father had severe deforming osteogenesis imperfecta (OI) was performed. The father had multiple congenital rib and extremity fractures. Subsequent fracture and deformity had suggested an autosomal recessive OI syndrome. However, fetal sonography at 18 weeks gestational age showed foreshortening of long bones in both legs and a reduced thoracic circumference, recapitulating, in part, the father's phenotype. This third reported case of early fetal diagnosis of autosomal dominant OI suggests that the fetal sonographic phenotype reflects that of the affected parent. Implications of this case for the application of fetal sonography in dominant OI syndromes are discussed.