[Antenatal diagnosis of achondrogenesis. Two successive cases in the same family].

Achondrogenesis is a rare case of fetal skeletal dysplasia. Achondrogenesis in lethal. That is a autosomal recessive fetal skeletal dysplasia. There is a very important dwarfism with extreme micromely, macrocephalia and brevity of chest. The authors enumerate the echographics, radiologics and histologics symptoms of this chondro-dysplasia. The authors comment rapidly the others diagnosis of lethal fetal skeletal dysplasia. Genetic consul is a necessity.