Menstrual irregularities and the perimenopause

The perimenopause is defined as the phase of women's reproductive life betw een the time when cycles change and become irregular until menopause. Compa red with younger women, follicle-stimulating hormone is elevated. In ovulat ory cycles, luteal insufficiency frequently occurs. Estrogen secretion is e levated throughout the menstrual cycle during some phases of the perimenopa use. Perimenopausal women are deficient in the hypothalamic-pituitary estro gen positive feedback mechanism on lutenizing hormone (LH) secretion. We ch allenged young and perimenopausal women with earlier follicular-phase estro gen boluses to attempt to induce LH surges. Whereas six of eight young wome n exhibited surges, only one of eight perimenopausal women had a surge of L H to estrogen challenge. Thus, perimenopausal changes involve mechanisms ot her than ovarian hypofunction. Complex central nervous system mechanistic c hanges also occur. A better understanding of the physiology in control mech anisms should allow for better symptom management of the perimenopause. (J Soc Gynecol Investig 2001;8:S65-S66) Copyright (C) 2001 by the Society for Gynecologic Investigation.