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Vaginal Bleeding


David H. Barad

, MD, MS, Center for Human Reproduction

Last full review/revision Mar 2020| Content last modified Mar 2020
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Abnormal vaginal bleeding includes

  • Menses that are excessive (menorrhagia or hypermenorrhea) or too frequent (polymenorrhea)

  • Bleeding that is unrelated to menses, occurring irregularly between menses (metrorrhagia)

  • Bleeding that is excessive during menses and occurs irregularly between menses (menometrorrhagia)

  • Premenarchal bleeding

  • Postmenopausal bleeding (ie, > 6 months after the last normal menses)

Pathophysiology of Vaginal Bleeding

Most abnormal vaginal bleeding involves

  • Hormonal abnormalities in the hypothalamic-pituitary-ovarian axis (most common)

  • Structural, inflammatory, or other gynecologic disorders (eg, tumors)

  • Bleeding disorders (uncommon)

With hormonal causes, ovulation does not occur or occurs infrequently. During an anovulatory cycle, the corpus luteum does not form, and thus the normal cyclical secretion of progesterone does not occur. Without progesterone, estrogen causes the endometrium to continue to proliferate, eventually outgrowing its blood supply. The endometrium then sloughs and bleeds incompletely, irregularly, and sometimes profusely or for a long time.

Etiology of Vaginal Bleeding

During the reproductive years, common causes of vaginal bleeding in women who are not known to be pregnant include

Abnormal uterine bleeding due to ovulatory dysfunction is the most common cause of abnormal vaginal bleeding during the reproductive years.

Vaginitis, foreign bodies, and trauma are common causes of vaginal bleeding before menarche. Sexual abuse and cancer are less common causes; however, prompt evaluation is required to rule these condition out.

PALM-COEIN classification system

PALM-COEIN classification system

Etiology references

  • 1. Practice bulletin no. 128: Diagnosis of abnormal uterine bleeding in reproductive-aged women. Obstet Gynecol 120 (1):197-206, 2012. doi: 10.1097/AOG.0b013e318262e320.

  • 2. Practice bulletin no. 136: Management of abnormal uterine bleeding associated with ovulatory dysfunction. Obstet Gynecol 122 (1):176-185, 2013. doi: 10.1097/

Evaluation of Vaginal Bleeding

Unrecognized pregnancy must be suspected and diagnosed in women of reproductive age because some causes of bleeding during pregnancy (eg, ectopic pregnancy) are life threatening.


History of present illness should include quantity (eg, by number of pads used per day or hour) and duration of bleeding, as well as the relationship of bleeding to menses and intercourse. Clinicians should ask about the following:

Review of systems should seek symptoms of possible causes, including the following:

Past medical history should identify disorders known to cause vaginal bleeding, including a recent spontaneous or therapeutic abortion and structural disorders (eg, uterine fibroids Uterine Fibroids Uterine fibroids are benign uterine tumors of smooth muscle origin. Fibroids frequently cause abnormal uterine bleeding, pelvic pain and pressure, urinary and intestinal symptoms, and pregnancy... read more Uterine Fibroids , ovarian cysts). Clinicians should identify risk factors for endometrial cancer Endometrial Cancer Endometrial cancer is usually endometrioid adenocarcinoma. Typically, postmenopausal vaginal bleeding occurs. Diagnosis is by biopsy. Staging is surgical. Treatment requires hysterectomy, bilateral... read more , including obesity, diabetes, hypertension, prolonged unopposed estrogen use (ie, without progesterone), and polycystic ovary syndrome. Drug history should include specific questions about hormone use.

If sexual abuse of a child is suspected, a structured forensic interview based on the National Institute of Child Health and Human Development (NICHD) Protocol can be used. It helps the child report information about the experienced event and improves the quality of information obtained.

Physical examination

Vital signs are reviewed for signs of hypovolemia (eg, tachycardia, tachypnea, hypotension).

During the general examination, clinicians should look for signs of anemia (eg, conjunctival pallor) and evidence of possible causes of bleeding, including the following:

The abdomen is examined for distention, tenderness, and masses (particularly an enlarged uterus). If the uterus is enlarged, auscultation for fetal heart sounds is done.

A complete gynecologic examination Physical Examination Most women, particularly those seeking general preventive care, require a complete history and physical examination as well as a gynecologic evaluation. Gynecologic evaluation may be necessary... read more Physical Examination is done unless abdominal examination suggests a late-stage pregnancy; then, digital pelvic examination is contraindicated until placental position is determined. In all other cases, speculum examination helps identify lesions of the urethra, vagina, and cervix. Bimanual examination is done to evaluate uterine size and ovarian enlargement. If no blood is present in the vagina, rectal examination is done to determine whether bleeding is gastrointestinal (GI) in origin.

If a child is unwilling to be examined or if the source if the child's bleeding is undetermined, the child may be given an anesthetic before the examination, and then vaginoscopy may be done to examine the vagina and cervix.

Red flags

The following findings are of particular concern:

  • Hemorrhagic shock (tachycardia, hypotension)

  • Premenarchal and postmenopausal vaginal bleeding

  • Vaginal bleeding in pregnant patients

  • Excessive bleeding

  • In children, difficulty walking or sitting; bruises or tears around the genitals, anus, or mouth; and/or vaginal discharge or pruritus

Interpretation of findings

Significant hypovolemia or hemorrhagic shock is unlikely except with ruptured ectopic pregnancy or, rarely, ovarian cyst (particularly when a tender pelvic mass is present).

In children, breast development and pubic or axillary hair suggest precocious puberty and premature menses. In those without such findings, the possibility of sexual abuse should be investigated unless an explanatory lesion or foreign body is obvious.

In women of reproductive age, examination may detect a causative gynecologic lesion or other findings suggesting a cause. If younger patients taking hormone therapy have no apparent abnormalities during examination and bleeding is spotty, bleeding is probably related to the hormone therapy. If the problem is excessive menstrual bleeding only, a uterine disorder or bleeding diathesis should be considered. Inherited bleeding disorders may initially manifest as heavy menstrual bleeding beginning at menarche or during adolescence.

In postmenopausal women, gynecologic cancer should be suspected.

If abnormal bleeding does not result from any of the usual causes, it may be related to changes in the hormonal control of the menstrual cycle.


All women of reproductive age require

  • A urine pregnancy test

Blood tests include a complete blood count (CBC) if bleeding is unusually heavy (eg, > 1 pad or tampon/hours) or has lasted at least several days or if findings suggest anemia or hypovolemia. If anemia is identified and is not obviously due to iron deficiency (eg, based on microcytic, hypochromic red blood cell [RBC] indices), iron studies are done.

Thyroid-stimulating hormone and prolactin levels are usually measured, even when galactorrhea is absent.

If a bleeding disorder is suspected, von Willebrand factor, platelet count, prothrombin time (PT), and partial thromboplastin time (PTT) are determined.

If polycystic ovary syndrome is suspected, testosterone and dehydroepiandrosterone sulfate (DHEAS) levels are measured.

Imaging includes transvaginal ultrasonography if women have any of the following:

Focal thickening of the endometrium that is detected during screening ultrasonography may require hysteroscopy or saline-infusion sonohysterography to identify small intrauterine masses (eg, endometrial polyps, submucous myomas).

Other testing includes endometrial sampling if examination and ultrasonography are inconclusive in women with any of the following:

  • Age > 35

  • Risk factors for cancer

  • Endometrial thickening > 4 mm

Sampling can be done by aspiration or, if the cervical canal requires dilation, by dilation and curettage (D & C). In postmenopausal women, hysteroscopy with D & C is recommended so that the entire uterine cavity can be assessed.

Treatment of Vaginal Bleeding

Hemorrhagic shock is treated. Women with iron deficiency anemia may require supplemental oral iron.

Geriatrics Essentials

Postmenopausal bleeding (bleeding > 6 months after menopause) is abnormal in most women and requires further evaluation to exclude cancer unless it clearly results from withdrawal of exogenous hormones.

In women not taking exogenous hormones, the most common cause of postmenopausal bleeding is endometrial and vaginal atrophy.

In some older women, physical examination of the vagina can be difficult because lack of estrogen leads to increased friability of the vaginal mucosa, vaginal stenosis, and sometimes adhesions in the vagina. For these patients, a pediatric speculum may be more comfortable.

Key Points

  • Pregnancy must be excluded in women of reproductive age even when history does not suggest it.

  • Anovulatory uterine bleeding is the most common cause of abnormal vaginal bleeding during the reproductive years.

  • Vaginitis, foreign bodies, and trauma are common causes of vaginal bleeding before menarche; sexual abuse is a less common cause but, if suspected, requires prompt evaluation.

  • Postmenopausal vaginal bleeding needs further evaluation to exclude cancer as the cause.

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