At least one in four women will develop one or more fibroids during their lifetime. They are most common in women aged 30-50 years and can run in families. Patients often have multiple fibroids, although some women have just one. Fibroids are three times more common in women of Afro-Caribbean descent than Caucasian women. Risk factors for the development of fibroids are:age; nulliparity; race; family history; obesity. There appears to be a decreased risk in smokers. Fibroids may be found during a routine examination or by chance during a scan for some other reason. On bimanual examination the uterus appears irregular in outline. An ultrasound scan can confirm the diagnosis. Women with menorrhagia and fibroids >12 cm and/or a palpable uterus should be referred to a specialist for further opinion. [With external links to current evidence and summaries]