Abnormal uterine bleeding (AUB) is uterine bleeding that lasts longer than usual or happens at an unexpected time. Bleeding can be heavier or milder than usual, and it can happen frequently or at random. Female hormone levels alter every month for the majority of women. The hormones oestrogen and progesterone are released during the ovulation process. An egg is discharged when a woman ovulates. When the ovaries fail to deliver an egg, AUB can develop. One indication of irregular uterine bleeding is vaginal bleeding between cycles. Abnormal uterine bleeding can also be defined as excessively heavy bleeding throughout your period. Menorrhagia is defined as significant bleeding during a period and/or bleeding that lasts longer than 7 days. Abnormal uterine bleeding can be caused by a number of factors. In the uterus, polyps or fibroids (small and big growths) can also cause bleeding. A thyroid condition, cervix infection, or uterine cancer are all rare causes of irregular uterine bleeding. A hormone imbalance is the most common cause of abnormal uterine bleeding in women. Doctors refer to dysfunctional uterine bleeding, or DUB, as a disorder caused by hormones. Hormone imbalance causes abnormal bleeding, which is more prevalent in teenagers and women approaching menopause.