Perimenopause

Perimenopause is the transitional period preceding menopause (defined retrospectively as 12 months without menses), typically spanning 2-8 years with average onset between ages 40 and 47. It is characterized by fluctuating rather than smoothly declining estradiol and progesterone, producing irregular menstrual cycles, vasomotor symptoms (hot flashes, night sweats), sleep disruption, mood changes, cognitive symptoms, and vaginal/genitourinary changes. Unlike postmenopause where hormonal decline is stable, perimenopause produces unpredictable hormonal swings that many women find particularly disruptive.

Evidence-based interventions are stratified by severity. For moderate-to-severe vasomotor symptoms affecting function, systemic hormone replacement therapy (estradiol plus progestogen for women with intact uterus) is first-line and most effective, with effect sizes 2-3 times any non-hormonal intervention. HRT initiated within 10 years of menopause onset or before age 60 has favorable risk-benefit profile for most women; the WHI-era concerns largely applied to older age at initiation and specific formulations. For women declining HRT, with contraindications, or seeking adjunct support, non-hormonal interventions have established but more modest evidence.

Non-HRT interventions with evidence include soy isoflavones (genistein and daidzein) at 40-80mg daily for vasomotor symptoms, black cohosh (standardized extract, typically Remifemin at 20-40mg daily) with 4-8 week onset, and cognitive behavioral therapy specifically designed for menopausal symptoms. Vitamin D (target above 30 ng/mL) and vitamin K2 (MK-7, 100-200mcg) support bone health during accelerated perimenopausal bone loss. Magnesium glycinate supports sleep and mood. Exercise (particularly resistance training for bone and muscle preservation) and Mediterranean-pattern diet produce benefits exceeding most supplement interventions.