Health & Fitness

What Is the Menstrual Cycle?

The menstrual cycle is the monthly series of hormonal changes that prepares the body for possible pregnancy. Cycle length is counted from the first day of one period to the first day of the next. For adults, cycles typically range from about 21 to 35 days, and 28 days is often used as an average.

Phases

Menstruation, the follicular phase, ovulation, and the luteal phase. Cycle length can vary from month to month, and irregular cycles are worth discussing with a healthcare provider.

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🔗 Related Terms

Luteal Phase Fertile Window Estimated Due Date (EDD)

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Last updated: September 27, 2026. This definition is for general educational purposes only. It is not financial, investment, tax, legal, or medical advice, and it does not recommend any product or course of action. For decisions about your own situation, consult a qualified professional.