Which type of osteogenesis imperfecta is the most lethal?

Which type of osteogenesis imperfecta is the most lethal?

• A. Type I
• B. Type II
• C. Type III
• D. Type IV

Answer: (B)

The most lethal form is the perinatal lethal type, because its extreme bone fragility drives multiple fractures before and during birth, which leads to a severely underdeveloped chest and rib deformities that restrict lung growth (pulmonary hypoplasia). At birth, this combination often results in respiratory failure, making survival unlikely. In contrast, milder or later-onset forms may cause significant deformities and morbidity but are compatible with life beyond the neonatal period.

The most lethal form is the perinatal lethal type, because its extreme bone fragility drives multiple fractures before and during birth, which leads to a severely underdeveloped chest and rib deformities that restrict lung growth (pulmonary hypoplasia). At birth, this combination often results in respiratory failure, making survival unlikely. In contrast, milder or later-onset forms may cause significant deformities and morbidity but are compatible with life beyond the neonatal period.