Dysfunctional uterine bleeding (DUB) may appear to be simply a defect in positive feedback and the lack of establishment of ovulatory cycles, most adolescents in fact are anovulatory during the first years following menarche and yet do not have DUB. In addition, the occasional ovulatory cycle stabilizes endometrial growth and allows more complete shedding.

Conditions that cause a lack of ovulation may also be likely to present with abnormal uterine bleeding, including eating disorders, weight changes, athletic competition, chronic illnesses, stress, drug abuse, endocrine disorders, and polycystic ovary syndrome. DUB connotes excessive, prolonged, unpatterned bleeding from the endometrium unrelated to structural or systemic disease, and thus other diagnoses should be excluded. Disorders of pregnancy and the possibility of pelvic infection must be determined early on. A patient's hematocrit count should be used in determining the amount of blood loss, in cases of possible excessive bleeding. Abnormal vaginal bleeding needs to be distinguished from uterine bleeding.

For more information go to the Center for Young Women's Health website.