<prompt> Answer this question truthfullyWhat is PALM-COEIN and how does it subcategorize abnormal uterine bleeding? What are the structural causes of abnormal uterine bleeding according to PALM-COEIN?  <response>: <reason> PALM-COEIN is a classification system used to subcategorize abnormal uterine bleeding. The acronym stands for Polyp, Adenomyosis, Leiomyoma, MalignancyHyperplasia, Coagulopathy, Ovulatory dysfunction, Endometrial, Iatrogenic, and Not otherwise classified. The PALM part of the acronym refers to structural causes of abnormal uterine bleeding, while the COEIN part refers to non-structural causes. The structural causes of abnormal uterine bleeding according to PALM-COEIN are: Polyp, Adenomyosis, Leiomyoma, and MalignancyHyperplasia. 