Anagen effluvium is the pathologic loss of anagen or growth-phase hairs. Classically, it is caused by radiation therapy to the head and systemic chemotherapy, especially with alkylating agents. : 753–4 Anagen effluvium is due to an acute injury to the hair follicles by an endogenous or exogenous cause, resulting in sudden diffuse shedding of structurally damaged hairs. Diffuse alopecia (hair loss) may occur over a period of days. The alopecia is non-scarring. Pathophysiology
Any insult that impairs mitosis of hair follicle keratinocytes can cause anagen effluvium. Disruption to cell division in the hair matrix makes the hair narrowed at its base and susceptible to breakage just above the zone of keratinisation. The necrotic matrix forms plugs consisting of melanin, keratin and inner root sheath which are extruded through the follicular opening. This process is known as trichomalacia. The main causes of anagen effluvium are an infection, a drug, a toxin, radiation or an autoimmune disease.Toxins that can interrupt hair growth include:

Chemotherapy agents, usually prescribed to treat cancer, especially when multiple drugs are used or they are in high dose. Severe hair loss is reported from doxorubicin, the nitrosoureas, and cyclophosphamide. Other causes are bleomycin, dactinomycin, daunorubicin, systemic fluorouracil, and high-dose methotrexate. Other medicines such as colchicine and ciclosporin (ciclosporin more often causes increased hair growth)
Poisons such as thallium, arsenic, gold and bismuth. Evaluation
A biopsy is rarely necessary, as a diagnosis can usually be made on history and physical exam findings alone. If a biopsy is requested or necessary for diagnosis, it can help exclude telogen effluvium.
Gynecologic hemorrhage represents excessive bleeding of the female reproductive system. Such bleeding could be visible or external, namely bleeding from the vagina, or it could be internal into the pelvic cavity or form a hematoma. Normal menstruation is not considered a gynecologic hemorrhage, as it is not excessive. Hemorrhage associated with a  pregnant state  or during delivery is an obstetrical hemorrhage. Types
Metrorrhagia (metro = womb, -rrhagia = excessive flow) is uterine bleeding at irregular intervals, particularly between the expected menstrual periods. Postcoital bleeding is vaginal bleeding after sexual intercourse. Causes
Causes of gynecologic bleeding include:

Hormonal
Anovulation is a common cause of gynecological hemorrhage. Under the influence of estrogen the endometrium (uterine lining) is stimulated and eventually such lining will be shed off (estrogen breakthrough bleeding). The anovulation chapter discusses its multiple possible causes. Longstanding anovulation can also lead to endometrial hyperplasia and facilitate the development of endometrial cancer. Neoplasm
Cancer of the uterus is always a concern, specifically when the bleeding occurs after menopause. Other types of cancer include cervical cancer; bleeding in that case can sometimes be triggered by postcoital bleeding. Cancers of the vagina or fallopian tubes are rare causes of hemorrhage. Uterine fibroids represent a common, benign condition that may lead to bleeding, specifically if the lesion affects the uterine cavity. Polyps of the uterine lining are a common cause of bleeding, but such bleeding tends to be light. Trauma
Sexual assault and rape can lead to injury and gynecological hemorrhage. Accidents to the lower abdomen may lead to internal or external bleeding.