Classification systems of Asherman's syndrome. An old problem with new directions

Intrauterine adhesion (IUA) formation and the resulting Asherman's syndrome (AS) is an unfortunate clinical condition that occurs when the endometrium is damaged as a consequence of trauma, such as vigorous curettage, infection, or some Müllerian anomaly. The most frequent symptoms include hypo/amenorrhea, infertility, and adverse reproductive outcomes. Prevention of IUA formation is essential; however, when present, accurate diagnosis and surgical intervention (hysteroscopic adhesiolysis) are required. The outcome of this treatment is based on the technique and the extent of surgery performed which depends on the severity and complexity of the disease. Hence its classification becomes particularly important to determine a standardized therapy for each case and patient counseling regarding the prognosis. In this article, we aim to describe the IUAs classification systems that have been proposed comparing the merits and demerits of each one.