Fetal Skeletal Dysplasias: Radiologic-Pathologic Classification of 72 Cases.

Objective: The aim of this study was to classify the fetal skeletal dysplasias (FSD) in a series of affected fetuses based on radio-pathologic criteria. Materials and methods: We gathered clinicopathologic data of 72 cases which were diagnosed among 5995 autopsies performed over a 8-year period. Results: The prevalence of FSD was 1.2:100 autopsies. The overall sex ratio (M:F) was 1.25. Gestational age was between 17 and 24 weeks in 60% of cases. The FSD were classified into 13 distinct pathologic groups. Four major groups were identified: (1) Osteogenesis imperfecta (21 cases, 29%); (2) FGFR3 chondrodysplasia (18 cases, 25%); (3) Ciliopathies (9 cases, 12%); and (4) Sulfation disorders (7 cases, 10%). Thanatophoric dysplasia type 1 and lethal osteogenesis imperfecta were the most common skeletal dysplasias. Conclusion: Our study demonstrates the usefulness of the radio-pathologic examination in the diagnosis and accurate classification of the FSD, thus enabling better targeting of genetic counseling.