Primary Dysmenorrhea: pathophysiology

The present study was conducted to investigate and analyze the recent and relevant studies about primary dysmenorrhea and its pathophysiology. Literature searches were performed electronically in PubMed, Medline, ISI, DOAJ, Springer, Embase. Web of Knowledge, DOAJ, Google Scholar and the Cochrane Library for original articles written in English and in Scielo, Lantidex, Imbiomed-L, Redalyc and Google Scholar for original articles written in Spanish. The searches included the key words (Mesh): menstruation, menstrual period, menstrual cycle, dysmenorrhea, primary dysmenorrhea, inflammatory substance and inflammatory markers. Publications from January 1980 to February 2021 were reviewed. Dysmenorrhea is the most common gynecologic condition experienced by menstruating women. It is characterized by crampy lower abdominal pain that can range widely in severity, and associated to others symptoms. Its overall impact often has significant medical and psychosocial implications. The hallmark of primary dysmenorrhea is painful menses in the absence of any associated macroscopic pathologic process, and it occurs in up to 50% of menstruating females and causes significant disruption in quality of life and absenteeism. An excessive or imbalanced amount of prostanoids and possibly eicosanoids released from the endometrium during menstruation have been mentioned as the main cause of primary dysmenorrhea. The uterus is induced to contract frequently and dysrhythmically, with increased basal tone and increased active pressure. Uterine hypercontractility, reduced uterine blood flow and increased peripheral nerve hypersensitivity induce pain. Diagnosis rests on a good history with negative pelvic evaluation findings. This narrative review investigated and analyzed the pathophysiology of primary dysmenorrhea and the implications of other chemical substances.