Number of antral follicles, ovarian volume, and vascular indices in asymptomatic women 20 to 39 years old as assessed by 3-dimensional sonography: a prospective cross-sectional study.

OBJECTIVES

Our aim was to elicit data representative of normal findings on 3-dimensional (3D) transvaginal gray-scale and power Doppler sonography of ovaries in women of fertile age.

METHODS

A total of 303 gynecologically asymptomatic white women 20 to 39 years old with spontaneous regular menstrual cycles were examined with transvaginal 3D gray-scale and power Doppler sonography on cycle days 4 to 8. We used a 6- to 12-MHz transducer. The ovarian volume, number and volume of antral follicles of 2 mm or larger, vascularization index, flow index, and vascularization-flow index were calculated using dedicated software. Results are presented separately for women with follicles of 2.0 to 10.0 mm and for those with at least 1 follicle larger than 10.0 mm for 3 age groups: 20 to 29, 30 to 34, and 35 to 39 years.

RESULTS

There were 214 women (71%) with follicles of 2.0 to 10.0 mm and 89 (29%) with follicles larger than 10.0 mm. In women with follicles of 2.0 to 10.0 mm, the right ovary was on average 0.8 cm3 larger and contained on average 1.2 more follicles than the left one. The ovarian volume, number of follicles, and total follicular volume decreased significantly with age in both ovaries (P = .000-.029): for the right ovary ovarian volume, the median (range) decreased from 8.4 (3.7-17.3) cm3 at 20 to 29 years to 6.5 (2.4-12.7) cm(3) at 35 to 39 years, the number of follicles from 14 (1-32) at 20 to 29 years to 8 (1-21) at 35 to 39 years, and the total follicular volume from 1.08 (0.01-3.10) cm3 at 20 to 29 years to 0.84 (0.03-2.00) cm3 at 35 to 39 years. The size of the largest follicle and the vascular indices manifested no clear changes with age in any ovary. In women with follicles larger than 10 mm, the number of follicles decreased with age in both ovaries.

CONCLUSIONS

We have elicited data representative of normal findings on 3D trans-vaginal sonography of ovaries in gynecologically asymptomatic white women of fertile age. Our gray-scale sonographic results may be used as reference values for general gynecology in populations similar to ours. Vascular indices must be interpreted with caution because of difficulties with standardization.