The Perimenopause Transition: Hormonal Variability and Tracking

What to expect in your 40s as ovarian reserve shifts and cycles vary in length.

Published by Period Circle Editorial Team • Reading Time: 7 min read • Public Reference Guide (No Login Required)

Erratic Estrogen Surges and Drops

Perimenopause is characterized by wildly fluctuating hormone levels rather than a steady decline.

Recognizing changes in cycle duration, night sweats, and mood changes as natural hormonal markers.

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