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You can get irregular periods at any time of life, but they can be a sign that menopause may be approaching. Your menstrual cycle may get shorter or longer. You may bleed for more days or fewer days. Your period may be lighter or heavier.

These changes are caused by changes in your hormone levels. When these changes happen, it is often a sign that you are in perimenopause, the stage leading up to menopause.

Talk to your doctor if you have any of the following changes in your bleeding, because they can be caused by problems that need treatment.

• Your periods are very heavy (you need to change a tampon or pad every hour or two).
• Your periods last more than six days.
• The time between your periods is shorter than 21 days from the start of one period to the start of the next.
• You get bleeding or spotting between periods.
• You bleed after having sex.

To find out more about perimenopause, see What is menopause?

This information is for educational use only, and is not a substitute for prompt professional medical advice. Readers should always consult a physician or other professional for advice and treatment. ©BMJ Publishing Group Limited 2008. All rights reserved.