Adenomyosis, one of the prevalent gynecologic problems in the female reproductive age, is an estrogen-dependent disease that is characterized by an ectopic endometrial-like tissue growth inside the myometrium [1]. It is linked to a decline in the quality of life because of irregular uterine bleeding and severe painful symptoms, such as pelvic pain and particularly dysmenorrhea [2].

Hysterectomy is the definitive cure for adenomyosis. However, it is not always the best treatment option, especially for women who want to preserve their uteri. Several hormonally-based drugs were proposed to control symptoms of adenomyosis, such as GnRH agonists, aromatase inhibitors, danazol, and levonorgestrel-releasing intrauterine devices (LNG-IUS) [3].

However, there is currently no agreement on the most effective therapy for managing women with adenomyosis who want to keep their uteri. Dienogest is an oral progestin with a high affinity to progesterone receptors. Dienogest effectively relieves pain associated with endometriosis and adenomyosis, because it causes atrophy of these ectopic islands by producing hypoestrogenemia [4].

Recently, there has been rising evidence that dienogest might be effective in controlling the symptoms of adenomyosis [[5], [6], [7]]. Recent studies showed that dienogest is an effective, important, well-tolerated drug as a long-term treatment for symptomatic adenomyosis, and it can be used as maintenance therapy [8,9].

Therefore, we aimed to conduct a systematic review and meta-analysis to investigate the role of dienogest in controlling pain and bleeding associated with adenomyosis.