Myasthenia gravis and premature ovarian failure.

Myasthenia gravis is believed to be an autoimmune disorder that results from antibodies directed against acetylcholine receptors. Not infrequently, it is associated with other autoimmune diseases, and, recently, several cases have been reported of coexistent premature ovarian failure. A 25-year-old nullgravida woman with myasthenia gravis became amenorrheic and then had ovarian failure with increased gonadotropin and negligible estrogen levels. Other endocrine functions were normal. An in vitro assay demonstrated the presence, in serum, of an inhibitor of binding to the luteinizing hormone (LH) receptor that suggested the possibility of a similar autoimmune process underlying the myasthenia gravis and premature ovarian failure. This could be the first case in which both disorders occurred with evidence for an LH receptor antagonist.