2d and 3d trans-vaginal sonography to determine cutoffs for ovarian volume and follicle number per ovary for diagnosis of polycystic ovary syndrome in indian women

Background: the purpose of the study was to determine cut-off values for ovarian volume (ov) and follicle number per ovary (fnpo) in indian women with polycystic ovary syndrome (pcos). methods: eighty six pcos women (rotterdam criteria) and forty five matched ovulatory and normo-androgenic women were recruited. a detailed 2d and 3d transvaginal scan was carried out in early follicular phase (d2-d5) in all patients. ovarian volume, follicle number per ovary, stromal volume, vascularization index (vi), vascularization flow index (vfi) and flow index (fi) were measured in pcos and controls. mann-whitney test and logistic analysis using proc logistic function of sas® (version 9.3) were used to calculate the best cut-offs for the diagnosis of pcos. results: mean ovarian volume was 13.7±5.89 and 5.06±2.44 (p<0.0001), fnpo was 19.18±6.89 and 7.13±3.51 (p<0.0001) in pcos and controls, respectively. the cut-offs for the diagnosis of pcos were 2d ov=6.15 cm³, 2d fnpo=12. by 3d scan, ov=7 cm³, fnpo=10, stromal volume=6 cm³, vi=4.546, vfi=2.925 and fi= 19.266. youden’s index (to select optimal predicted probability cut-off) was the highest for 2d fnpo (0.88786). 2d fnpo showed the highest specificity and sensitivity (auc), 0.95238 and 0.93548, for the diagnostic accuracy of pcos. conclusion: 2d and 3d trans-vaginal scans are equally accurate for assessment of ovarian morphology. fnpo has better diagnostic accuracy for pcos compared to ovarian volume. cut-off for fnpo and ov in indian pcos women is 12 and 6.15 cm³ by 2d, 10 and 7 cm³ by 3d trans-vaginal scan.