Adenomyosis-associated infertility: an update of the immunological perspective

Adenomyosis is characterized by the invasion of endometrial glands and stroma into the myometrium. Its clinical manifestations often include dysmenorrhoea, excessive menstrual bleeding and infertility. Reduced pregnancy and live birth rates and an increased miscarriage rate are observed in women with adenomyosis. This review summarizes relevant advances and presents the underlying mechanisms of adenomyosis-associated infertility from an immunological perspective. Individuals with adenomyosis exhibit imbalances in immune cell subpopulations and the endocrine hormone-immunomodulatory axis. These immunological alterations may be key contributors to, or at least accomplices in, impaired endometrial receptivity. In addition, adenomyosis often occurs in association with endometriosis, uterine leiomyoma or endometrial polyps, which are pathogenetically relevant; their similarities and differences are discussed from an immunological perspective. The clinical diagnostic criteria of adenomyosis are not perfect, and the pathogenesis remains to be fully explored. Therefore screening for effective targets for early diagnosis and treatment at the cellular and molecular levels from the immunological point of view holds great potential, which will be of great importance in preventing this disease and improving women's reproductive health.