Menstrual cycle

Periods and fertility in the menstrual cycle

Find out what happens when in the menstrual cycle, including ovulation, periods and the fertile time.

Period problems

Treatments for period problems, including painful, missing or heavy periods, ovulation pain, and PMS.

How can I avoid pregnancy?

How to recognise when you're likely to be fertile during your menstrual cycle to help you plan or avoid pregnancy.

Why haven't I started my periods?

Find out why your periods haven't started, including when to see your GP and the possible causes and treatments.

Early menopause: Johanna's story

Johanna was 17 when doctors told her she had suffered premature ovarian failure.

Girls' bodies Q&A

Answers to questions about girls' bodies, including puberty and sex, vaginal discharge, and pregnancy.

Menstrual cycle: animation

This animation explains in detail how the menstrual cycle works.

Media last reviewed: 21/10/2017

Next review due: 21/10/2020

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