Recurrent pregnancy loss (RPL) represents an unresolved problem for contemporary gynecology and obstetrics. In fact, it is not only a relevant complication of pregnancy, but is also a significant reproductive disorder affecting around 5% of couples desiring a child. The current knowledge on RPL is largely incomplete, since nearly 50% of RPL cases are still classified as unexplained. Emerging evidence indicates that the endometrium is a key tissue involved in the correct immunologic dialogue between the mother and the conceptus, which is a condition essential for the proper establishment and maintenance of a successful pregnancy. The immunologic events occurring at the maternal–fetal interface within the endometrium in early pregnancy are extremely complex and involve a large array of immune cells and molecules with immunoregulatory properties. A growing body of experimental studies suggests that endometrial immune dysregulation could be responsible for several, if not many, cases of RPL of unknown origin. The present article reviews the major immunologic pathways, cells, and molecular determinants involved in the endometrial dysfunction observed with specific application to RPL.

Endometriosis affects approximately 10% of premenopausal women worldwide. Despite its impact on quality of life, the delay in diagnosing this chronic disease is well known. Many patients with endometriosis report having suffered from dysmenorrhea and chronic pelvic pain in adolescence or at a young age. However, this painful symptom is often highly underestimated and considered a normal and transient symptom in young women. The real prevalence of endometriosis in adolescence remains uncertain. Some authors recently described at least one ultrasound feature of endometriosis in 13.3% of a general population of adolescent girls, which increased to 35.3% in young girls with severe dysmenorrhea. Dysmenorrhea is classified as primary dysmenorrhea or secondary dysmenorrhea. Primary dysmenorrhea is defined as a menstrual pain without organic disease, while secondary dysmenorrhea is defined as a menstrual pain associated with organic pelvic pathology. Since endometriosis represents the main cause of secondary dysmenorrhea in adolescents and young women, it is important to determine whether the patient has primary dysmenorrhea or additional suggestive symptoms related to endometriosis. Endometriosis in adolescent patients is a challenging problem with clinical and pathological differences compared with its presentation in premenopausal women. Adolescents and young women with dysmenorrhea and painful symptoms that suggest endometriosis should be referred to dedicated endometriosis centers for an early diagnosis and appropriate medical and surgical management. This paper aims to describe the role of dysmenorrhea in adolescents and the management of these young patients to confirm or exclude endometriosis.