Intensity of menstrual pain and estimated angle of uterine flexion

To assess the impact of ultrasound-estimated uterus position on the intensity of pelvic pain.

Descriptive analytical study.

Tertiary university gynecology unit.

181 consecutive patients with pelvic pain.

Each woman underwent physical examination, transvaginal sonography and filled self-administered questionnaires on pain using a 10-cm visual analog scale (VAS).

Visual analog scale score of menstrual pain, intermenstrual pain and dyspareunia was related to uterine version (ante- or retroversion) and the angle of uterine flexion (actual angle between cervix and uterine body) evaluated by transvaginal sonography.

Estimated uterine version was not associated with the intensity of any type of pain. The estimated angle of flexion was higher in retroverted than in anteverted uteri (182.3° ± 50.3° vs. 142.3° ± 24.2°, p < 0.0001). Intensity of menstrual pain was lowest with flexion between 150° and 210° (4.9 ± 3.1) (p = 0.002), intermediate with flexion <150° (6.3 ± 2.8) and highest with flexion ≥210° (7.9 ± 2.3). Severe menstrual pain was more prevalent with flexion ≥210° (77.7%) than between 150° and 210° (31.4%; p = 0.0008) or <150° (45.2%; p = 0.005). The intensity of intermenstrual pain and dyspareunia were not associated with the angle of flexion. In multiple regression analysis, the angle of flexion was independently related only to the intensity of menstrual pain (r = 0.272; p = 0.002).

In women with pelvic pain, ultrasound-estimated uterine flexion represents an independent risk for intense menstrual pain.