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If you can't get pregnant because you have problems ovulating, it means that your ovaries are not releasing eggs at all or only releasing eggs occasionally. If you don't ovulate each month, then you won't have an egg available to be fertilized by sperm.

This problem is very common. About a third of women who can't get pregnant have this problem.¹

The most common reason that some women don't ovulate is a condition called polycystic ovary syndrome (PCOS for short). PCOS is caused by an imbalance of hormones. It means that eggs grow in the ovaries, but are not released into the fallopian tubes.

If you have PCOS, you may also get acne and grow unwanted hair on your face and body.² Your periods are likely irregular, if you get them at all.

PCOS is more common in women who are overweight. To find out more, see our articles about Polycystic ovary syndrome.

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.