Endometriosis is a chronic inflammatory disease, defined by the presence of endometrial tissue outside the uterine cavity. It causes symptoms such as dysmenorrhea, chronic pelvic pain, dyspareunia, infertility, with great loss of quality of life for the patient. The objective of the study was to compare, through a meta-analysis, GnRH analogues, which are considered clinical first line treatment for endometriosis, versus dienogest, a selective oral progestin in the treatment of endometriosis. A systematic review was conducted to select the studies. In total, 31 articles were found. Four studies met criteria, the following variables were analyzed: pelvic pain, dyspareunia and induration of the Pouch of Douglas after treatment and it was evaluated the presence of side effects during treatment: hot flushes, headache and BMD loss. There was no difference between the dienogest group and GnRH analogue group when it was evaluated maintenance of lower abdominal pain, dyspareunia, induration of the Pouch of Douglas after treatment and hot flushes during treatment. Besides those results, the dienogest group had a lower incidence of headache and less BMD loss. The treatment of endometriosis continues to be a challenge, even with new treatment options such as new drugs (dienogest) and surgical procedures. This meta-analysis provides evidence of the absence of dienogest inferiority compared with GnRH analogues with less BMD loss and less headache incidence.