Transabdominal versus transvaginal ultrasound in the diagnosis of polycystic ovaries in a population of randomly selected women.

A study was conducted which compared transvaginal and transabdominal ultrasound in determining the prevalence of polycystic ovaries in a population of women. Women, chosen randomly from electoral rolls, were sent a letter inviting them to take part in a study determining the presence of polycystic ovaries. A transvaginal and transabdominal ultrasound scan was performed on day 5-9 of their menstrual cycles. A total of 187 women (mean age 33 years) took part in the study. The prevalence of polycystic ovaries was 21% (40/187) by transabdominal ultrasound and 27% (36/134) by transvaginal ultrasound. No differences existed between women with polycystic and normal ovaries with respect to uterine size and endometrial thickness. Mean ovarian volume was larger in women with polycystic ovaries irrespective of the use of hormonal contraception or breast feeding. There was no difference in the prevalence of polycystic ovaries diagnosed by transabdominal or transvaginal ultrasound in the group of randomly selected women. However, almost 20% of the women declined a transvaginal ultrasound examination. Copyright 1994 International Society of Ultrasound in Obstetrics and Gynecology