Excessive amount or duration of menstrual flow, at more or less regular intervals

Menorrhagia is defined as excessive amount or duration of menstrual flow, at more or less regular intervals. Menorrhagia is characterized by unusually heavy menstruation or prolonged menstrual flow. The average amount of blood loss during a normal menstrual period is 40 to 50 ml. With menorrhagia, a woman may lose 80 ml or more. It rarely signifies a serious underlying disorder.

Menorrhagia is distinguished from, but may overlap with, Metrorrhagia (irregular or frequent flow, noncyclic), Menometrorrhagia (frequent, excessive, irregular flow; menorrhagia plus metrorrhagia), Polymenorrhea (frequent flow, cycles of 21 days or less), Intermenstrual bleeding (bleeding between regular menses), and Dysfunctional uterine bleeding - DUB (abnormal endometrial bleeding of hormonal cause and related to anovulation).

  • Distinguish from, but may overlap with:
    • Metrorrhagia - irregular or frequent flow, noncyclic  
    • Menometrorrhagia - frequent, excessive, irregular flow (menorrhagia plus metrorrhagia)  
    • Polymenorrhea - frequent flow, cycles of 21 days or less  
    • Intermenstrual bleeding - bleeding between regular menses  
    • Dysfunctional uterine bleeding (DUB) - abnormal endometrial bleeding of hormonal cause and related to anovulation

System(s) affected: Reproductive

Incidence/Prevalence in USA: Abnormal bleeding is common; prevalence varies with definition (endometrial carcinoma: about 40,000 new cases per year)

Predominant age:

  • Menarche to menopause; about 50% of cases occur after 40 years of age
  • Dysfunctional bleeding is fairly common in adolescence and near menopause

Predominant sex: Female only

Menorrhagia -  Mesentery, mesenteric

Menorrhagia (primary) 626.2
Menorrhagia, climacteric 627.0
Menorrhagia, menopausal 627.0
Menorrhagia, postclimacteric 627.1
Menorrhagia, postmenopausal 627.1
Menorrhagia, preclimacteric 627.0
Menorrhagia, premenopausal 627.0
Menorrhagia, puberty (menses retained) 626.3

Sings and symptoms

  • “Excessive” menstrual flow defined subjectively varies greatly from woman to woman (average normal menstrual flow is about 30-40 mL per cycle)
  • Useful historical features include:
    • Bleeding substantially heavier than the patient’s usual flow  
    • Bleeding lasting more than 7 days  
    • Flow associated with passage of significant clots  
    • Anemia
  • The following symptoms tend to suggest that cycles are ovulatory:

    • Regular menstrual interval  
    • Mid-cycle pain (mittelschmerz)  
    • Dysmenorrhea  
    • Premenstrual symptoms - breast soreness, mood changes, etc.
  • Abdominal pain or cramps at other times of the cycle may be associated with structural causes:

    • Myomas  
    • Polyps  
    • Ovarian tumors
  • Hirsutism or acne

    • May accompany polycystic ovarian syndrome


Menorrhagia can be caused by a variety of causes. These include: Imbalance of hormones (estrogen and progesterone), Fibroids (benign uterine tumors), Pelvic infection, Endometrial disorder, Intrauterine device, Hypothyroidism, Pregnancy, Ovarian cyst or tumor and other hormonal causes.

  • Hypothyroidism
  • Endometrial proliferation/excess/hyperplasia:
    • Anovulation, oligo-ovulation  
    • Polycystic ovarian disease (PCOD)  
    • Ovarian tumor  
    • Obesity  
    • Hormone (estrogen) therapy
  • Endometrial atrophy:
    • Postmenopause  
    • Prolonged progestin or oral contraceptive administration
  • Local factors:
    • Endometrial polyps  
    • Endometrial neoplasia  
    • Adenomyosis/endometriosis  
    • Uterine myomata (fibroids)  
    • Intrauterine device (IUD)  
    • Uterine sarcoma
  • Coagulation disorders:
    • Thrombocytopenia, platelet disorders  
    • von Willebrand disease  
    • Leukemia  
    • Ingestion of aspirin or anticoagulants  
    • Renal failure/dialysis

Risk Factors

  • Obesity
  • Anovulation
  • Estrogen administration (without progestin)
  • Prior treatment with progestational agents or oral contraceptives increases the risk of endometrial atrophy, but decreases the risk of endometrial hyperplasia or neoplasia

Differential Diagnosis

  • Pregnancy complications:
    • Threatened abortion  
    • Incomplete abortion  
    • Ectopic pregnancy
  • Nonuterine bleeding:
    • Cervical ectropion/erosion  
    • Cervical neoplasia/polyp  
    • Cervical or vaginal trauma  
    • Condylomata  
    • Atrophic vaginitis  
    • Foreign bodies
  • Pelvic inflammatory disease (PID):
    • Endometritis  
    • Tuberculosis


  • Pregnancy test
  • CBC to assess severity of blood loss, exclude thrombocytopenia and leukemia
  • In selected cases:
    • TSH - elevated in hypothyroidism  
    • Platelet count, bleeding time, prothrombin time (PT), partial thromboplastin time (PTT) for coagulation screen  
    • Creatinine, BUN  
    • Serum progesterone - 5-20 ng/mL (15.9-63.6 nmol/L) in luteal phase, < 1 ng/mL (< 3.18 nmol/L) in follicular phase or anovulatory cycle
Drugs that may alter lab results: Progestins used prior to endometrial biopsy may cause decidualization and obscure true diagnosis

Pathological Findings

Vary with cause: see Causes Special Tests Endometrial biopsy detects hyperplasia, dysplasia, or atrophy. If done prior to expected menses, may also help make the diagnosis of anovulation or luteal phase defect. Imaging
  • Ultrasonography to evaluate adnexal masses or fibroids suspected from pelvic exam
  • Transvaginal ultrasonography to measure thickness of endometrium may help distinguish bleeding due to atrophy from bleeding due to hyperplasia
  • Computerized tomography used in investigation of potentially malignant pelvic masses
Diagnostic Procedures
  • Pelvic and rectal examination
  • Pap smear
  • Endometrial biopsy
  • Diagnostic dilatation and curettage
  • Hysteroscopy


  • Most cases can be managed as outpatients in office or emergency department
  • Hospitalize for bleeding accompanied by orthostatic hypotension or hematocrit < 25%
  • Rule out pregnancy complications and non-uterine bleeding
  • Treat severe or life-threatening bleeding acutely:
    • Intravenous estrogen  
    • Curettage if necessary  
    • Hysterectomy in extreme case
  • Proceed to identify underlying cause of bleeding and treat to prevent recurrence
    • Hormonal therapy  
    • Dilatation and curettage for hormone-unresponsive cases  
    • Consider endometrial ablation or hysterectomy in persistent cases where fertility is not desired  
    • Specific treatment for neoplasia, polyps, systemic disease, etc.  
    • Patients who desire fertility may also need appropriate treatment for anovulation, endometriosis, myomata, etc.
ACTIVITY As tolerated. Resting with feet elevated may be helpful. DIET Iron supplementation may help correct for increased blood loss PATIENT EDUCATION Information about side effects of medications


Drugs of choice
  • For acute control of severe bleeding:
    • Estrogen, conjugated (Premarin) 25 mg IV every 4 hours up to 6 doses until bleeding abates
  • For less severe bleeding or after control of acute bleeding:
    • Medroxyprogesterone acetate (Provera) 10-30 mg daily for 5-10 days  
    • Any combination oral contraceptive, (usually one of the “high dose” oral contraceptives) one tablet 4 times a day for 5-7 days
  • To prevent heavy bleeding in subsequent cycles:
    • Medroxyprogesterone acetate 10-20 mg daily for 10 days per month  
    • Usual cyclic dose of a combination oral contraceptive
  • For endometrial atrophy in postmenopausal woman:
    • Estrogen plus progesterone replacement therapy
  • To estrogen, oral contraceptives, or progestins:
    • Pregnancy  
    • Breast or endometrial cancer  
    • Thromboembolic disease, past or present  
    • Impaired liver function
  • Nausea and vomiting are common from IV estrogen; antiemetics are helpful
  • Estrogen may precipitate acute intermittent porphyria or cholestatic jaundice in susceptible individuals
Significant possible interactions: Refer to manufacturer’s profile of each drug Alternative Drugs
  • Non-steroidal prostaglandin-synthetase inhibitors (naproxen, mefenamic acid, ibuprofen, and others) can reduce blood loss with ovulatory cycles and reduce dysmenorrhea
  • Norethindrone acetate (Aygestin) 2.5-10 mg daily for 10 days per month, during the assumed latter half of menstrual cycle
  • Danazol and GnRH agonists are also effective therapies, but more likely to have adverse side effects
  • Megestrol acetate (Megace) 40 mg daily for 10 days per month (caution required to prevent progression to endometrial carcinoma)
  • Megestrol acetate (Megace) 40 mg daily continuously to treat atypical hyperplasia


Patient Monitoring
  • Varies with cause of bleeding
  • Medical treatment of hyperplastic/dysplastic endometrium should be followed by repeat biopsy to confirm that histologic structure has returned to normal
Prevention Pap smear and pelvic examination annually Possible Complications Anemia Expected Course/Prognosis
  • Varies with cause of bleeding
  • Most patients with hormonal causes will respond to hormonal manipulation
Associated Conditions Metrorrhagia; menometrorrhagia; androgenic disorders Age-Realted Factors Pediatric: Genital bleeding prior to puberty can result from trauma, foreign bodies, vaginal infection, or exogenous hormone administration Geriatric: Genital atrophy may predispose to bleeding with minimal trauma. Neoplasm of ovary or endometrium must be ruled out. Others:
  • In adolescence, irregular bleeding due to anovulation and immaturity of the hypothalamic-pituitary-ovarian axis is common
  • Beyond age 35-40, endometrial dysplasia and endometrial carcinoma are significant causes of bleeding. Obtain endometrial sampling before attempting hormonal treatment.
Pregnacy Bleeding in pregnancy is not menorrhagia. Complications of pregnancy or cervical/vaginal lesions should be considered. ICD-9-CM 621.0 Polyp of corpus uteri 621.3 Endometrial cystic hyperplasia 621.8 Other specified disorders of uterus, NEC 626.2 Excessive or frequent menstruation 626.3 Puberty bleeding 626.4 Irregular menstrual cycle 626.6 Metrorrhagia 626.8 Disorders of menstruation and other abnormal bleeding from female genital tract, other 627.0 Premenopausal menorrhagia 627.1 Postmenopausal bleeding Author(s) Donald A. F. Nelson, MD

Provided by ArmMed Media
Revision date: June 20, 2011
Last revised: by Sebastian Scheller, MD, ScD