Dienogest in the treatment of rectovaginal endometriosis: effect on deep dyspareunia and sexual function

Abstract

To investigate the efficacy of dienogest (DNG) in treating deep dyspareunia (DD) and in improving sexual function in women with rectovaginal endometriosis. Prospective open-label cohort pilot study. This study included premenopausal sexually active women with rectovaginal endometriosis suffering DD (more than 6 month duration and intensity > 80 mm on a 100 mm visual analogue scale). The diagnosis of rectovaginal endometriosis was based on vaginal and rectal examinations and it was confirmed by transvaginal ultrasonography. The criteria for exclusion from the study were: therapies for endometriosis other than non-steroidal anti-inflammatory drugs in the 3 months before inclusion in the study (6 months for GnRH analogues); unwillingness to tolerate menstrual changes; undiagnosed vaginal bleeding; obstructive uropathy or bowel stenosis and evidence of complex adnexal cysts. Eligible patients received DNG (2 mg/day) for 6 months. The primary end-point of the study was to assess the changes in DD during treatment. The secondary objective of the study was to evaluate the changes in sexual function, which was evaluated by using the Female Sexual Function Index (FSFI). Outcomes were assessed after 3 and 6 months of treatment. 23 women were included in the study; the mean (± SD) age of the study population was 34.2 (± 3.7) years. The mean (± SD) intensity of DD was 9.1 (± 0.7) cm; it significantly decreased at 3-months of treatment (7.4 ± 1.4 cm; p<0.001). At 6-month treatment the intensity of DD (6.5 ± 1.6 cm) was lower than at baseline (p<0.001) and at 3-month treatment (p<0.001). The total FSFI score was significantly higher at 3-month treatment than at baseline (p < 0.001); there was no significant difference in the total FSFI score between 3- and 6- month treatment (p = 0.188); at both 3- and 6-month treatment the mean total FSFI score remained below the threshold for sexual dysfunction. At 6-month treatment significant improvements were observed in the following subscores: lubrication (p=0.011), orgasm (p=0.010) and pain (p=0.016). In patients with severe DD caused by rectovaginal endometriosis, 6-month treatment with DNG causes a significant decrease in the intensity of this symptom that however persists with moderate intensity. Although an improvement was observed in the total FSFI score, it remained below the threshold for sexual dysfunction.