Fibroids must be differentiated from:
- ovarian tumours:
- ovarian cysts - cystic, rarely cause menstrual disturbance, and grow more rapidly
- ovarian fibroma - often with ascites as Meig's syndrome
- ovarian carcinoma - usually irregular
- tubo-ovarian inflammatory mass - uterus not enlarged, mass tender, blood tests usually show leucocytosis, raised ESR
- pregnancy - associated amenorrhoea, uterus soft, foetus detectable by ultrasound from 7th week onwards
- uterine endometriosis - uterus only slightly enlarged, usually dysmenorrhoea
- diverticular disease - identifiable by barium enema
- colonic carcinoma - identifiable by sigmoidoscopy
In women over 35 years, it is not uncommon for uterine fibroids to co-exist with endometrial carcinoma.