3-D volumetric and vascular analysis of the urethrovaginal space in young women with or without vaginal orgasm.

INTRODUCTION

The existence of the G-spot is controversial.

AIM: To evaluate, by the use of three-dimensional (3-D) ultrasonography, the anatomic structures of the urethrovaginal space.

METHODS

Nineteen (Group I) eumenorrheic young women who experienced, and 20 (Group II) who did not experience a vaginal orgasm underwent two-dimensional (2-D) and 3-D ultrasonography and color Doppler analysis of the urethrovaginal space and of the clitoris during the early follicular phase of the menstrual cycle.

MAIN OUTCOME MEASURES: 2-D ultrasonographic evaluation of the urethrovaginal space, and color Doppler evaluation of the urethrovaginal main feeding artery and dorsal clitoral arteries; 3-D volume calculation of the urethrovaginal space, and 3-D power Doppler analysis of vascular indices of the urethrovaginal space and clitoral body (vascularization index, flow index, vascularization flow index); hormonal evaluation.

RESULTS

The 3-D reconstruction of the urethrovaginal space demonstrated a gland-like aspect with small feeding vessels. The total length (19.1 + or - 2.7 mm vs. 17.5 + or - 2.1 mm; P = 0.047), measured with 2-D ultrasound, and the 3-D mean volume (0.59 + or - 0.13 mL vs. 0.26 + or - 0.07 mL; P < 0.001) of the structures contained in the urethrovaginal space were significantly higher in Group I than in Group II. The mean time since the last intercourse was 31 + or - 9 hours in Group I and 18 + or - 3 hours (P = 0.033) in Group II. The urethrovaginal space vascularization, the clitoral volume and vascularization, and the circulating hormonal values did not significantly differ among the two groups. The mean volume of the structures contained in the urethrovaginal space was correlated with time since intercourse (r = 0.685; P = 0.021) and with serum testosterone (r = 0.637; P = 0.032) and androstenedione (r = 0.744; P = 0.011).

CONCLUSIONS

The structures we observed in the urethrovaginal space have a gland-like aspect and their volume is correlated with both serum androgen concentrations and time since intercourse.