Both dienogest and GnRH agonists (like gonadorelin) work about the same for pain relief and preventing endometriosis lesions after surgery, but they have different side‑effects: dienogest often causes more vaginal bleeding, while GnRH agonists tend to cause hot flushes.

This systematic review and meta-analysis compared the efficacy of dienogest (DNG) and gonadotropin-releasing hormone (GnRH) agonists in the management of endometriosis-related symptoms following surgical intervention, their related adverse effects, and lesion recurrence. A comprehensive literature search was conducted across PubMed, EMBASE, and Cochrane Central databases, encompassing publications from January 2000 to May 2025. Randomized controlled trials comparing postoperative medical treatment with either DNG or a GnRH agonist were systematically reviewed for inclusion. Eligible participants were women aged 18 to 45 years who underwent laparoscopic surgery for endometriosis excision. Statistical analyses utilized a random-effects model to compute pooled risk ratios (RR) and mean differences with 95% confidence intervals. Primary outcomes assessed included pelvic pain, dyspareunia, dysmenorrhea, chronic pelvic pain, lesion recurrence by imaging, and incidence of adverse events. Six studies met the inclusion criteria. No significant differences were observed between the groups concerning pelvic pain and dyspareunia Visual Analog Scale (VAS) scores at 3 and 6 months post-surgery. DNG was associated with a significantly higher risk of vaginal bleeding (RR 4.16, CI 1,98-8.75), and a lower incidence of hot flushes (RR 0.33, CI 0.11-0.98). No other adverse events demonstrated significant inter-group differences. Lesion recurrence at 6 months assessed by postoperative imaging was not statistically different between groups (RR 0.62, CI 0.23-1.70). This meta-analysis shows that DNG and GnRH agonists demonstrate comparable efficacy in postoperative pain management and lesion recurrence after laparoscopic endometriosis excision. These findings, however, should be interpreted with caution due to the high risk of bias of the included studies. DNG appears to be more frequently associated with vaginal bleeding, whereas GnRH agonists are more often linked to hot flushes.