What's the next step for a patient with prolonged menstrual bleeding for 15 days and normal vitals?

Next Step: Pregnancy Test (β-hCG)

The immediate next step for a patient with prolonged menstrual bleeding for 15 days and normal vitals is to perform a pregnancy test (β-hCG), making option C or D the correct answer. This is mandatory before any further diagnostic or therapeutic interventions, as pregnancy-related complications (including ectopic pregnancy, threatened abortion, or incomplete abortion) are critical diagnoses that must be ruled out first 1, 2.

Algorithmic Approach to This Patient

Step 1: Rule Out Pregnancy (MANDATORY)

• All reproductive-age women with abnormal uterine bleeding must be tested for pregnancy before proceeding with any other evaluation or treatment 1, 2
• Pregnancy-related bleeding can present as prolonged bleeding and may indicate:
  • Threatened or incomplete abortion 3
  • Ectopic pregnancy 4
  • Gestational trophoblastic disease
• This is non-negotiable regardless of patient history or contraceptive use 1

Step 2: Assess for Anemia (Concurrent with Pregnancy Test)

• CBC should be obtained simultaneously to evaluate for anemia from blood loss, particularly checking hemoglobin and ferritin 5
• Given 15 days of continuous bleeding, anemia is highly likely and will guide urgency of treatment 2, 6
• Option D (CBC and β-hCG) is the most complete initial answer as it addresses both critical needs simultaneously

Step 3: Additional Initial Laboratory Work

• TSH and prolactin levels to rule out ovulatory dysfunction 1, 2
• Consider coagulation studies if there is personal/family history of bleeding disorders (epistaxis, easy bruising, dental bleeding) 2, 5

Step 4: Imaging (After Pregnancy Ruled Out)

• Pelvic ultrasound (transvaginal and transabdominal with Doppler) is the first-line imaging study to identify structural causes 1, 2
• This evaluates for polyps, adenomyosis, leiomyomas, and endometrial hyperplasia/malignancy 1
• However, ultrasound should NOT be performed before ruling out pregnancy, as management differs dramatically if pregnancy is present

Why NOT the Other Options First?

Pelvic Ultrasound (Option A) - Premature

• While ultrasound is the appropriate first-line imaging study for abnormal uterine bleeding, it should only be performed after pregnancy is ruled out 1
• If the patient is pregnant, the ultrasound findings and subsequent management would be entirely different
• Performing ultrasound before pregnancy testing wastes time and resources

Dilation and Curettage (Option B) - Dangerous Without Pregnancy Test

• D&C without first ruling out pregnancy could be catastrophic if the patient has a desired pregnancy or ectopic pregnancy 1
• D&C is reserved for:
  • Acute hemorrhage unresponsive to medical management 5
  • Endometrial sampling when hyperplasia/malignancy is suspected 1
  • Hemodynamically unstable patients after initial stabilization 2
• This patient has normal vitals, so D&C is not indicated as the next immediate step

Clinical Pitfalls to Avoid

• Never assume a patient cannot be pregnant based on history alone - always test 1, 2
• Do not delay pregnancy testing to obtain imaging first, as this reverses the proper diagnostic sequence
• Recognize that "normal vitals" does not rule out significant anemia - a CBC is essential given 15 days of bleeding 5
• Be aware that up to 20% of women with heavy menstrual bleeding have an underlying inherited bleeding disorder, particularly if there is flooding, clots ≥1 inch, or family history 6, 7

Answer Selection

Option D (CBC and β-hCG) is the best answer as it addresses both mandatory initial steps: ruling out pregnancy and assessing for anemia from prolonged blood loss 1, 2, 5. If only one test can be selected, Option C (pregnancy test alone) takes priority as it is the absolute prerequisite before any other intervention 1, 2.