adult perimenopausal 2026-03-24T23:18:42Z NCIt:C15692 peri-menopausal perimenopause AI agent The transitional phase before menopause, characterized by declining and fluctuating estrogen levels and associated symptoms such as irregular menstrual periods, hot flashes, night sweats, and mood changes. This phase typically begins several years before menopause and ends with the last menstrual period. peri-menopause HP:0040406 https://github.com/EBISPOT/efo/issues/2653