Perimenopause
Perimenopause is the transition leading up to menopause, staged using the STRAW+10 criteria and marked by increasingly irregular cycles as ovarian hormone production becomes erratic, per current staging criteria.
Symptoms
Irregular periods (the hallmark), hot flashes, sleep disruption, mood changes, and brain fog -- vasomotor symptoms affect up to 74% of women during this transition.
Causes and risk
This is a natural transition for everyone with ovaries, though surgical or medical triggers (like chemotherapy) can bring it on earlier; racial and ethnic background influences symptom burden and duration.
How it is evaluated
Diagnosis is clinical, without routine FSH testing, in women 45 and older -- a Choosing Wisely recommendation reflecting how much cycle-to-cycle hormone levels fluctuate during this transition, making a single lab value unreliable.
Treatment
Hormone therapy follows the same 2022 Menopause Society guidance used for menopause, with the same "under 60 or within 10 years" favorable window, alongside non-hormonal options for symptom relief.
When to seek care
Heavy or prolonged bleeding, bleeding between periods, or any bleeding after 12 months without a period all warrant evaluation -- perimenopausal bleeding patterns can mask other conditions, and endometrial sampling is often recommended for abnormal bleeding at age 45 or older.