<prompt> Causes of dysfunctional uterine bleeding can be:a Uterine polypb Fibroidc Granulosa cell tumourd Irregular ripening of endometriume Irregular shedding of endometriumabbccdde  <response>: DUB is defined as a state of abnormal uterine bleeding without any clinically detectable organic pelvic pathology.DUB is of 2 types: 1. Anovulatory 80 2. Ovulatory 20Anovulatory 80: Threshold bleeding of puberty menorrhagia Metropathia hemorrhagica cystic glandular hyperplasia Premenopausal DUB Atrophy of endometrium.Ovulatory 20: Irregular ripening of corpus luteum Irregular shedding of corpus luteum IUCD insertion Following sterilization operation. 