Birth prevalence rates of skeletal dysplasias

Abstract
This study establishes the prevalence rates at birth of the skeletal dysplasias which can be diagnosed in the perinatal period or during pregnancy. Using a population-based register of congenital anomalies, a prevalence rate of 3.22 0/000 was observed. The most frequent types of skeletal dysplasia were achondroplasia and osteogenesis imperfecta (0.64 0/000, 1/15 000 births), thanatophoric dysplasia and achondrogenesis (0.28 0/000). The mutation rate for achondroplasia was higher in our material than in the other studies: 3.3 times 10-5 per gamete per generation. Our study demonstrates that prenatal diagnosis by ultrasound is possible in some skeletal dysplasias.