Development of the gonadotrophic resistant ovary syndrome in myasthenia gravis: suggestion of similar autoimmune mechanisms

Abstract

A woman with myasthenia gravis who developed hypergonadotropic amenorrhea was studied. This patient fulfilled all accepted criteria for the diagnosis of the gonadotropic resistant ovary syndrome: high levels of serum lutropin and FSH by radioimmunoassay and urinary gonadotropin excretion by bioassay, low serum estradiol, lack of response to exogenous gonadotropin and ovaries with multiple non-stimulated primordial follicles. The serum of this patient contained a substance which behaved like a gamma globulin, inhibited FSH specific binding to receptors in an in vitro system. This inhibitor was looked for in further patients with hypergonadotropic amenorrhea, other immunological diseases or myasthenia gravis with normal menses. Ovarian biopsy was not available in these patients. In all except one who had the association of myasthenia gravis and hypergonadotropic amenorrhea, the inhibitor was not detected. Development of antibodies directed against gonadotropin receptors or a receptor related membrane domain may play a role in the mechanism of failure of gonadotropin stimulation in some patients with the gonadotropin resistant ovary syndrome.