Ovarian size and vascularization as assessed by three-dimensional grayscale and power Doppler ultrasound in asymptomatic women 20–39 years old using combined oral contraceptives

Abstract

BackgroundThe aim of this study is to estimate ovarian volume, number and volume of antral follicles, and ovarian power Doppler vascular indices as assessed by three-dimensional (3D) transvaginal grayscale and power Doppler ultrasound in women using combined oral contraceptives (COC). Study DesignTwo hundred thirteen gynecologically asymptomatic women 20–39 years old using COC were examined with transvaginal 3D grayscale and power Doppler ultrasound on cycle day 4–8 (first cycle day is first day of withdrawal bleeding). We used a Voluson E8 ultrasound system with a 6–12-MHz transvaginal transducer. Ovarian volume, number and volume of antral follicles ≥2 mm, vascularization index (VI), flow index (FI) and vascularization flow index (VFI) were calculated using the virtual organ computer-aided analysis (VOCAL™) and sonography-based automated volume calculation (SonoAVC™) software. Results are described separately for women with follicles 2.0–10.0 mm and for those with at least one follicle >10.0 mm for two age groups: 20–29 years (n=166) and 30–39 years (n=47). Results are also compared between women on monophasic (n=151) and triphasic (n=59) COC, and between women using COC with older (n=110) and newer (n=100) progestins and different doses of estrogen. ResultsOne hundred eighty-nine (89%) women had follicles 2.0–10.0 mm, and 24 (11%) had follicle(s) >10.0 mm. The proportion of women with follicle(s) >10.0 mm did not differ between women with different types of COC. In women with follicles 2.0–10.0 mm, the right ovary was larger (mean difference 0.5 cm3 [95% confidence interval 0.22–0.82]) and contained more follicles (mean difference 1.5 [0.52–2.56]) than the left one in the age group 20–29 years. The same differences between the right and left ovary were seen in women 30–39 years old, but they were not statistically significant. In both ovaries, the number of antral follicles 2.0–10.0 mm [median (range)] was significantly higher in women 20–29 than in those 30–39 years old [11 (2–34) vs. 8 (1–26), p=.012 for the right ovary; 9 (0–28) vs. 7 (1–28), p=.035 for the left ovary]. Ovarian volume tended to be smaller in women 20–29 than in those 30–39 years old, but the differences were not statistically significant. Size of the largest follicle, total follicular volume and vascular indices manifested no clear differences between the age groups. For all 378 ovaries with follicles ≤10 mm, ovarian volume ranged from 1 to 16 cm3 (median 5), total follicular volume ranged from 0.03 to 2.7 cm3 (median 0.7), VI ranged from 0.0 % to 13.4% (median 0.97), FI ranged from 0 to 38 (median 25), and VFI ranged from 0.0 to 4.7 (median 0.3). ConclusionsOur results show estimated ranges of 3D grayscale and power Doppler ultrasound measurements in ovaries of women using COC.