ABSTRACT
Hypersecretion of luteinizing hormone (LH) occurs in approximately 40% of women who have poly cystic ovaries.1 The risk of infertility and miscarriage is raised in these patients.1
Many reasons have been proposed for the aetiology of pituitary over secretion of LH. These include increased pulse frequency of gonadotrophin releasing hormone (GnRH) secretion, altered pituitary sensitivity to GnRH, hyperinsulinaemic stimulation of the pituitary gland and perturbed ovarian-pituitary feedback of steroid hormones.2 None of these hypotheses fully explains hypersecretion of LH and there is good evidence to suggest that hypersecretion of LH occurs secondary to a disturbance of non-steroidal ovarian-pituitary feedback.2 A suggested hypothesis is that women with the polycystic ovary syndrome (PCOS) who hypersecrete LH have deficient production of an ovarian non-steroidal factor that normally inhibits LH secretion. Although this notion is attractive, the evidence to date remains inconclusive.
