Bilateral femoral hypoplasia and maternal diabetes mellitus: case report and review of the literature.

The case of a 21-week fetus with bilateral femoral hypoplasia and bowing related to maternal diabetes mellitus is reported. The femoral middiaphysis (site of hypoplasia and bowing) showed intramembranous ossification instead of the normal endochondral ossification, thus pointing to a transient inhibition of chondrogenesis of the mesenchymal femoral model as the causative mechanism. This finding is correlated with the recent experimental advances in the field of limb development in vertebrates.