GNRH1 and Dysmenorrhea: Compared with the HIFU alone group, the HIFU combined with GnRH-a group had a higher rate of uterine volume reduction (MD 7.51, 95% CI 5.84-9.17, <i>p</i> < 0.00001), smaller adenomyotic lesion volume (MD 4.11, 95% CI 2.93-5.30, <i>p</i> < 0.00001), lower VAS score for dysmenorrhea (MD 1.27, 95% CI 0.54-2.01, <i>p</i> = 0.0007) and menstrual volume score (MD 0.88, 95% CI 0.73-1.04, <i>p</i> < 0.00001), and lower CA125 level (SMD 0.31, 95% CI 0.05-0.56, <i>p</i> = 0.02) after the procedure.