Period & Menstrual Cycle Guide

Understand your period and menstrual cycle phases with clear, expert-written guidance — from menarche through perimenopause.

The four phases

Menstrual, follicular, ovulatory and luteal — each phase has its own hormonal signature, energy level and emotional landscape.

What's normal, what's not

Cycles between 21 and 35 days are typical. Heavy bleeding, severe pain or skipped periods deserve a conversation with your doctor.