Ergotamine as a possible cause of Möbius sequence: additional clinical observation.

A case of Möbius sequence after exposure to ergotamine during early development is reported. Vascular disruption is one of the theories explaining the pathogenesis of Möbius sequence. Ergotamine can cause vasospasm and a prolonged and marked increase in uterine tone. This is the second report suggesting a relation between maternal ingestion of ergotamine in early pregnancy and subsequent Möbius sequence in a child.