Donnez O, et al. - The efficacy of a selective progesterone receptor modulator, ulipristal acetate, vs a gonadotropin-releasing hormone antagonist, linzagolix, was reported in a case of severe uterine adenomyosis. The patient born in 1981 presented to a private clinic and infertility research unit because of heavy menstrual bleeding, pelvic pain, and dysmenorrhea; magnetic resonance imaging (MRI) confirmed diffuse and disseminated uterine adenomyosis in this case. Treatment of 5 mg UPA daily was first provided to the patient for one course of 3 months. Discontinuation of this therapy was done because of MRI revealing a worsened aspect. Initiation of a once-daily dose of 200 mg linzagolix orally was done 1 year later, for 3 months; this was followed by another 3-month course of 100 mg once daily. The patient remained in amenorrhea, and had a very significant improvement in symptoms during the 12-week course of once-daily 200 mg linzagolix. MRI showed decrease in the uterine volume, and significant regression in adenomyotic lesions. Researchers identified this work to be the first reported use of linzagolix, a new oral gonadotropin-releasing hormone antagonist.