What should be checked before starting oral contraceptive pills (OCPs) in a female patient with bleeding?

Pre-Initiation Evaluation for OCPs in a Woman with Bleeding

Before starting oral contraceptive pills in a woman with bleeding, the only essential requirement is to reasonably exclude pregnancy—no pelvic ultrasound, FSH, TSH, or endometrial biopsy is routinely needed for healthy women. 1

Essential Pre-Initiation Requirement

The single most critical step is pregnancy exclusion. The CDC explicitly classifies pregnancy as a Category 4 contraindication to OCPs, meaning the risks clearly outweigh any benefits. 1 The FDA drug label confirms that OCPs are contraindicated in pregnancy. 2

• Pregnancy testing (urine or serum HCG) is the only mandatory test before initiating OCPs in a woman with abnormal bleeding. 1
• If pregnancy cannot be reasonably excluded but clinical suspicion is low, OCPs can be started with follow-up pregnancy testing in 2-4 weeks. 1

Tests That Are NOT Required

Pelvic Ultrasound (Option A)

• Pelvic ultrasound is classified as Class C by the CDC, meaning it does not contribute substantially to safe OCP use and is not required for healthy women. 1
• Ultrasound is only indicated if you suspect structural pathology (fibroids, polyps) or other gynecological conditions, not as routine pre-OCP screening. 3

FSH Testing (Option B)

• FSH is not mentioned as necessary for contraceptive initiation in any guideline. 1
• FSH testing is relevant for diagnosing conditions like PCOS or premature ovarian failure, but not for OCP initiation in a bleeding woman. 3

TSH Testing (Option C)

• TSH is not required before OCP initiation unless there are specific clinical signs of thyroid disease. 1
• While thyroid disease can cause abnormal bleeding, it should be evaluated based on clinical suspicion (e.g., weight changes, fatigue, goiter), not as routine pre-OCP screening. 3

Endometrial Biopsy (Option D)

• Endometrial biopsy is not required before starting OCPs in women with bleeding. 1
• The CDC guidelines state that among healthy women, no examinations or tests beyond pregnancy exclusion are needed before OCP initiation. 1
• Endometrial biopsy would only be considered if there were specific risk factors for endometrial pathology (age >45, obesity, prolonged anovulation, failed medical management). 3

Clinical Approach to Bleeding Before OCP Initiation

If clinically warranted, evaluate for underlying conditions before starting OCPs:

• Rule out pregnancy first with urine or serum HCG. 1
• Consider sexually transmitted infections, particularly in reproductive-aged women. 4
• Assess for structural lesions (fibroids, polyps) only if clinically indicated by history or examination findings. 4
• Evaluate medication interactions that might affect bleeding patterns. 3

Important Caveat

OCPs can actually be used to TREAT abnormal uterine bleeding. The American College of Obstetricians and Gynecologists recommends monophasic combined oral contraceptives containing 30-35 μg ethinyl estradiol as first-line treatment for prolonged menstrual bleeding, as they reduce menstrual blood loss by inducing regular shedding of a thinner endometrium. 4 This means that in many cases, the bleeding itself is not a contraindication to OCPs but rather an indication for their use. 5