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The diagram below shows the parts of your body that are involved in getting pregnant.

• Your ovaries contain your eggs. Inside your ovaries are millions of pre-eggs, called follicles. These were formed before you were born, but only some will become full-grown eggs.
• Your fallopian tubes carry full-grown eggs from your ovaries to your womb. The tubes are lined with tiny hairs to push the eggs along. If an egg joins a sperm in the tube, this is called fertilization.
• Your womb is where the fertilized egg starts growing. The lining of the womb is called the endometrium.
• Your cervix is the neck of your womb. Sperm have to pass through it to get to the egg.
• Your vagina is the passage leading up to your womb.

To get pregnant you need to release an egg from one of your ovaries. This is called ovulation. This normally happens every month as part of your menstrual cycle.

Your menstrual cycle begins during puberty. It lasts about 28 days, but it can be shorter or longer. It's controlled by your hormones. Your hormones tell your ovaries to release an egg and help your body prepare for pregnancy.

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.