Uterine contraction in the development of Möbius syndrome.

We report a patient with Möbius syndrome. The birth defect in this child is probably the result of both vasoconstriction and uterine contractions brought on by ergotamine taken during the sixth week of pregnancy. We propose that vasoconstrictive or mechanical effects, or both, of abortifacient drugs such as ergotamine and misoprostol may account for other cases of Möbius syndrome, and we suggest that uterine contraction from any cause, at about the sixth or seventh week of pregnancy, may cause this birth defect. Further observational studies are needed to verify this hypothesis.