A fetus with upper limb amelia, "caudal regression" and Dandy-Walker defect with an insulin-dependent diabetic mother.

We describe the fetus delivered to an insulin-dependent diabetic woman who had had a previous large, stillborn, non-malformed male infant and a normal female infant. The present fetus had a most unusual combination of malformations which to date had not been described in diabetic embryopathy. The anomalies include: upper limb amelia, "caudal regression" with bilateral absence of the fibulae, unilateral absence of a femur and ipsilateral oligodactyly; undescended testes; atrial septal defect; multiple vertebral and rib anomalies with cervical scoliosis and right webbed neck; left cleft lip and cleft palate; severe micrognathia; left microtia with atresia of the ear canal; and central nervous system defects including hydrocephalus with the Dandy-Walker malformation, asymmetry of the lateral ventricles, abnormal frontal gyral formation, and ependymal and ganglion cell heterotopias of the spinal cord. The pathogenesis of diabetic embryopathy is discussed.