Abnormal (Dysfunctional) Uterine Bleeding Workup

Updated: Mar 29, 2022
  • Author: Thomas Michael Price, MD; Chief Editor: Richard Scott Lucidi, MD, FACOG  more...
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Laboratory Studies

Laboratory studies for patients with abnormal uterine bleeding (AUB) may include human chorionic gonadotropin (HCG), complete blood count (CBC), Pap smear, endometrial sampling, thyroid functions and prolactin, liver functions, coagulation studies/factors, and other hormone assays as indicated. [43]

Human chorionic gonadotropin

The most common cause of abnormal uterine bleeding during the reproductive years is abnormal pregnancy. Rule out threatened abortion, incomplete abortion, and ectopic pregnancy.

Complete blood count

Document blood loss. Charting the number of menstrual pads used per day, or keeping a menstrual calendar is helpful.

Obtain a baseline CBC count for hemoglobin and hematocrit to evaluate for anemia. Obtain a differential with platelet count if hematologic disease is suspected.

Pap smear

Pap smear should be up to date. Cervical cancer still is the most common gynecologic cancer affecting women of reproductive age in the world population.

Endometrial sampling

Perform a biopsy to rule out endometrial hyperplasia or cancer in high-risk women aged ≥45 years and in younger women at extreme risk for endometrial hyperplasia/carcinoma due to unopposed estrogen (PCOS, obesity), failed medical management, and persistent AUB. Women with chronic eugonadal anovulation, obesity, hirsutism, diabetes, or chronic hypertension are at particular risk.

Most biopsies will confirm the absence of secretory endometrium.

Thyroid and liver function tests

Perform thyroid function tests and prolactin because hyperthyroidism, hypothyroidism, and hyperprolactinemia are associated with ovulatory dysfunction. Identify and treat these conditions.

Obtain liver function tests if alcoholism or hepatitis is suspected. Any condition affecting liver metabolism of estrogen can be associated with abnormal uterine bleeding.

Coagulation factors

Von Willebrand disease and factor XI deficiency initially might manifest during adolescence.

Primary or secondary thrombocytopenia can be factors in the mature patient.

Tailor the choice of laboratory tests to the presenting clinical situation. Generally speaking, when coagulopathies are present, heavy bleeding is regular and associated with ovulation.

Other hormone assays

For the patient with recurrent anovulatory bleeding, the mainstay of management is treatment of correctable disease.

Obtain a hormonal complete evaluation in women with signs of hyperandrogenism, such as those with polycystic ovarian syndrome, 21 hydroxylase deficiency, or ovarian or adrenal tumors, as dictated by their respective conditions.

Women in menopausal transition usually can be followed without an extensive hormonal evaluation.


Imaging Studies

Generally, patients with abnormal uterine bleeding can be managed appropriately without the use of expensive imaging studies.

Ultrasonography, especially saline infusion sonography, can be used to examine the status of the endometrium, myometrium, and ovaries. Endometrial hyperplasia, endometrial carcinoma, endometrial polyps, uterine fibroids, and ovarian cysts/masses can be suspected or diagnosed with this technology.



Rule out endometrial carcinoma in all patients at high risk for the condition, including patients with the following characteristics:

  • Morbid obesity

  • Diabetes or chronic hypertension

  • Age >45 years

  • Longstanding, chronic eugonadal anovulation

Traditionally, carcinoma was ruled out by endometrial sampling via dilation and curettage (D&C). More recently, endometrial sampling in the office via aspiration, curetting, or hysteroscopy has become popular and is also relatively accurate.

Saline infusion sonography can be helpful in distinguishing individuals who have bleeding with thick endometrium from those with thin, denuded endometrium, endometrial polyps, uterine fibroids, or other uterine pathology.

Most endometrial biopsy specimens will show proliferative or dyssynchronous endometrium.