Patients with severe idiopathic constipation are almost exclusively women. Common presenting features include lower abdominal pain, irregular and painful menstruation, and a past history of gynaecological surgery. Pelvic ultrasonography was undertaken in 26 patients with severe idiopathic constipation and 21 age matched control women to detect any gynaecological abnormality. No difference was found in ovarian, uterine or pelvic vein morphology or size. The abdominal pain in these patients is related to the bowel disorder, and minor abnormalities of pelvic morphology on ultrasound are probably incidental findings.