Endometrial hyperplasia, included in this PALM category of abnormal bleeding, is more common in women who are obese or who have a history of chronic anovulation. When endometrial hyperplasia is associated with atypical cells, it can progress to cancer or occur concurrently with it. While endometrial hyperplasia and endometrial cancer occur most commonly among post-menopausal women, most patients with endometrial cancer have abnormal bleeding, and thus the diagnosis must be considered in women during the reproductive years. Coagulopathies (blood clotting disorders): Heavy menstrual bleeding can be related to coagulopathies. Von Willebrand disease is the most common coagulopathy, and most women with von Willebrand disease have heavy menstrual bleeding. Of women with heavy menstrual bleeding, up to 20% will have a bleeding disorder. Heavy menstrual bleeding since menarche is a common symptom for women with bleeding disorders, and in retrospective studies, bleeding disorders have been found in up to 62% of adolescents with heavy menstrual bleeding. Ovulatory dysfunction: Ovulatory dysfunction or anovulation is a common cause of abnormal bleeding that may lead to irregular and unpredictable bleeding, as well as variations in the amount of flow including heavy bleeding. Endocrine, or hormonal, causes of ovulatory disorders include polycystic ovary syndrome (PCOS), thyroid disorders, hyperprolactinemia, obesity, eating disorders including anorexia nervosa or bulimia,  or to an imbalance between exercise and caloric intake.
Vaginal bleeding is any expulsion of blood from the vagina. This bleeding may originate from the uterus, vaginal wall, or cervix. Generally, it is either part of a normal menstrual cycle or is caused by hormonal or other problems of the reproductive system, such as abnormal uterine bleeding. Vaginal bleeding during pregnancy can be normal, especially in early pregnancy. However, bleeding may also indicate a pregnancy complication that needs to be medically addressed. During pregnancy bleeding is usually, but not always, related to the pregnancy itself. Regular monthly vaginal bleeding during the reproductive years, menstruation, is a normal physiologic process. During the reproductive years, bleeding that is excessively heavy (menorrhagia or heavy menstrual bleeding), occurs between monthly menstrual periods (intermenstrual bleeding), occurs more frequently than every 21 days (abnormal uterine bleeding), occurs too infrequently (oligomenorrhea), or occurs after vaginal intercourse (postcoital bleeding) should be evaluated.The causes of abnormal vaginal bleeding vary by age, and such bleeding can be a sign of specific medical conditions ranging from hormone imbalances or anovulation to malignancy (cervical cancer, vaginal cancer or uterine cancer). In young children, or elderly adults with cognitive impairment, the source of bleeding may not be obvious, and may be from the urinary tract (hematuria) or the rectum rather than the vagina, although most adult women can identify the site of bleeding. When vaginal bleeding occurs in prepubertal children or in postmenopausal women, it always needs medical attention.