Background: Transvaginal ultrasonography is an accurate and reliable technique for measuring ovarian size. However, there is no consensus as to the normal ovarian size in post-menopausal women. The purpose of this study was to establish normal values for ovarian volume in postmenopausal age.
Methods: A prospective study was undertaken, in which the ovaries of 311 healthy post-menopausal women were examined by transvaginal ultrasonography. Menopausal age ranged from one to more than 15 years. Three dimensions of each ovary were measured and ovarian volume of every menopausal year was calculated.
Results: Curvilinear relationships were found between ovarian volume and menopausal age. Ovarian volume (as plotted on the nomogram) shows a progessive decrease from 8.6 +/- 2.3 cm3 in the first menopausal year, to 2.2 +/- 1.4 cm3 after more than 15 years after the menopause.
Conclusions: These data represent a comprehensive characterization of normal ovarian volumes related to postmenopausal age. These baseline values provide the data which will assist the physician to obtain the sonographic diagnosis of abnormal ovarian size, thus eventually establishing early diagnosis of ovarian tumors.