Pulsatile LH secretion in women with premenstrual syndrome (PMS): Evidence for normal neuroregulation of the menstrual cycle

Abstract

The premenstrual syndrome (PMS) has been proposed to result from excessive exposure to and/or withdrawal of brain opioid activity during the luteal phase. Because hypothalamic opioids are believed to modulate GnRH secretion, in part under the influence of ovarian steroids, we performed longitudinal studies of gonadotropin and ovarian steroid secretion across ovulatory, symptomatic cycles of 17 PMS patients and 8 normal volunteers. Pulsatile LH secretion was measured every 10 min for 8 hr at times when central opioid activity was expected to be low (early follicular phase), high (mid-luteal phase; ML), and declining (late luteal phase). In both subject groups, a cycle-phase effect was observed for LH pulse frequency (p=p=0.002), and for the transverse mean concentrations of LH (p=0.05), FSH (p2) (p=p=p=<0.05). The similar changes in luteal LH pulse frequency fail to provide evidence that GnRH secretion is impaired, thus challenging the view that the neuroregulation of the menstrual cycle in women with PMS is markedly altered.