What investigations are recommended for abnormal uterine bleeding?

From the Guidelines

The investigation of abnormal uterine bleeding should begin with a thorough history and physical examination, followed by laboratory tests including complete blood count, pregnancy test, thyroid function tests, and coagulation studies. Transvaginal ultrasound is the first-line imaging modality to evaluate uterine anatomy and endometrial thickness, as recommended by the American College of Radiology Appropriateness Criteria 1. For women over 40 or those with risk factors for endometrial cancer, endometrial sampling is recommended, typically via endometrial biopsy in the office setting, with a sensitivity of 99.6% for detecting endometrial carcinoma 1. Some key points to consider when investigating abnormal uterine bleeding include:

• The use of saline infusion sonohysterography to better characterize intracavitary lesions
• Hysteroscopy for direct visualization of the uterine cavity and targeted biopsy
• MRI for complex cases or when adenomyosis is suspected
• Additional tests such as cervical cytology, STI screening, and prolactin levels if menstrual irregularity suggests hyperprolactinemia The sequence of investigations should be tailored to the patient's age, risk factors, and clinical presentation, with the goal of identifying structural abnormalities, endocrine disorders, or malignancy that may be causing the bleeding, as outlined in the ACR Appropriateness Criteria 1. It is essential to prioritize the most recent and highest quality studies, such as those published in 2020 by the American College of Radiology 1, when making recommendations for investigations of abnormal uterine bleeding.

From the Research

Investigations for Abnormal Uterine Bleeding

Investigations for abnormal uterine bleeding are crucial for determining the underlying cause and guiding treatment. The following are some of the recommended investigations:

• Complete blood cell count to rule out anemia or coagulopathy 2
• Pregnancy test to exclude pregnancy-related complications 2
• Hormone levels (estradiol, progesterone, follicle-stimulating hormone, luteinizing hormone, prolactin, testosterone, dehydroepiandrosterone sulfate) to evaluate ovulatory function and hormonal imbalances 2
• Thyroid function tests to assess for thyroid dysfunction 3, 2
• Liver function tests to evaluate liver health 2
• Coagulation profile to identify coagulopathy 3, 2
• Transvaginal ultrasonography to evaluate the uterus and ovaries for structural abnormalities such as polyps, fibroids, or adenomyosis 3, 2, 4
• Saline infusion sonohysterography to detect endometrial polyps and submucous leiomyomas 3, 4
• Hysteroscopy with biopsy to provide a definitive diagnosis of intrauterine lesions and endometrial hyperplasia or cancer 3, 2, 4
• Endometrial biopsy to evaluate for endometrial hyperplasia or cancer, especially in women over 35 years old or those with risk factors for endometrial cancer 3, 2

Special Considerations

In women using hormonal contraception, investigations should include an assessment of compliance, a thorough history and complete physical examination to exclude organic causes of bleeding, and a targeted laboratory evaluation 5. Pregnancy and misuse of oral contraceptive pills are frequent causes of abnormal uterine bleeding, and bleeding is common during the first three months of oral contraceptive pill use 5.

Diagnostic Approach

A systematic approach to diagnosis, including a careful history, physical and pelvic examinations, and the selective use of adjunctive diagnostic tests and procedures, is essential for evaluating abnormal uterine bleeding 2. The choice of investigation depends on the patient's presentation, age, and medical history, as well as the suspected underlying cause of the bleeding 3, 2, 4, 6.