The ovaries

What are they?

The ovaries are small, oval-shaped organs – about the size and shape of an almond – that are part of the female reproductive system. Each woman has two ovaries, one on either side of the womb, in the lower part of the tummy (pelvis). The ovaries produce eggs and female hormones, which make menstruation (periods) and pregnancy possible.

What do they do?

Each month, in women of childbearing age, one of the ovaries produces an egg. The egg passes down the fallopian tube to the womb (uterus). If the egg is not fertilised by a sperm it passes out of the womb and is shed, along with the lining of the womb, as part of the monthly period.

The ovaries also produce the female sex hormones, oestrogen and progesterone. As a woman nears the menopause (‘change of life’) the ovaries make less of these hormones, and periods gradually stop.

Other organs are very close to the ovaries (see diagrams below). These include:

• The ureters, which drain urine from the kidneys to the bladder.
• The bladder.
• The back passage (rectum).
• The lower part of the small bowel.
• The omentum (a membrane which surrounds all of the pelvic and abdominal organs and keeps them in place). It is also called the peritoneum.
• Groups of lymph nodes.

The ovaries and their surrounding structures

Side view of the abdomen showing the peritoneum surrounding the abdominal organs