Detailed definition
Early menopause refers to natural menopause occurring between ages 40 and 45. It affects roughly 5% of women. Causes include genetics (family history of early menopause), smoking (which advances menopause by 1–2 years on average), some autoimmune conditions, prior chemotherapy or pelvic radiation, and idiopathic factors. Early menopause is associated with longer cumulative estrogen-deprived years than typical menopause, which translates to higher lifetime risks of osteoporosis, cardiovascular disease, cognitive decline, and possibly all-cause mortality. For this reason, major societies (NAMS, IMS, ACOG) recommend hormone therapy for women with early menopause at least until the average age of natural menopause (around 51), absent contraindications, even if symptoms are mild.
Why it matters in menopause
Women with early menopause are sometimes told they "don't need" HRT because they aren't severely symptomatic, or because they are still young. This reverses the actual risk-benefit math: for women with early menopause, HRT is usually not optional comfort treatment — it is replacement of a hormone the body should still be producing, prescribed to protect long-term organ systems through what should be peak reproductive years.
Related terms
Sources
External references: Wikipedia.