Perimenopause is often overshadowed by its better-known counterpart, menopause — a point in time for menstruators after going 12 months without a period. But for millions of period- have r s, typically in their late 30s to early 50s, perimenopause marks a transitional phase toward menopause, signaling the end of reproductive years. Multi-faceted symptoms such as irregular cycles, hot flashes, mood swings, brain fog, sleep disturbances and low libido can make the journey challenging, with limited expert guidance available.