Prenatal diagnosis of osteochondrodysplasias in high risk pregnancy.

We collected data on 39 prenatally diagnosed osteochondrodysplasias. We detected 30 (76.9%) cases in the first and second trimesters, including 18 (46.2%) with two twins before the 24th week of gestation. Of 39 cases 11 (28.2%) had osteogenesis imperfecta (OI) type II. Verification of the prenatal diagnosis was attempted in 26 cases on the basis of the data obtained from ultrasonographs, radiographs, external examination, and autopsy protocols. The prenatal diagnosis was confirmed in 19 (73%) fetuses. In 13 cases verification was not possible because one or several investigations could not be performed. Counselling followed all identified cases with osteochondrodysplasia. We present the pedigree of two families indicating the possibility of early prenatal diagnosis of achondrogenesis type I and metatropic dysplasia. We propose indications for ultrasonographic anatomical screening with subsequent phenotype analysis in high risk pregnancy to provide for the prenatal detection of malformations and hereditary diseases.