In a 41-year-old asymptomatic woman requesting contraception, what is the most appropriate pre‑prescription investigation?

No Routine Investigation Required Before Prescribing Contraception

For an asymptomatic 41-year-old woman requesting contraception, no investigation from the options provided (FSH, TSH, transvaginal ultrasound, or endometrial biopsy) is routinely necessary before prescribing most contraceptive methods. 1

Evidence-Based Pre-Prescription Requirements

The CDC guidelines explicitly state that the following examinations and tests are not needed routinely to provide contraception safely to a healthy client 1:

• Pelvic examinations (unless inserting an IUD or fitting a diaphragm) 1
• Cervical cytology or other cancer screening, including clinical breast exam 1
• Laboratory tests for lipid, glucose, liver enzyme, and hemoglobin levels or thrombogenic mutations 1
• HIV screening 1

What IS Actually Required

For Combined Hormonal Contraceptives

• Blood pressure measurement only (Class A: essential and mandatory) 1
• Blood pressure can even be obtained by the woman in a nonclinical setting (e.g., pharmacy) and self-reported to the provider if access to healthcare is limited 1

For Other Methods

According to CDC classification tables 1:

• Implants, injectables, progestin-only pills: No examination required (Class C) 1
• IUDs: Bimanual examination and cervical inspection required (Class A) 1
• Condoms, cervical cap, spermicide: No examination required (Class C) 1

Why None of the Listed Options Are Appropriate

FSH Testing (Option A)

• FSH levels are not reliable for determining when a woman is no longer fertile 1
• The assessment of follicle-stimulating hormone levels to determine fertility status "might not be accurate" 1
• FSH testing is classified as Class C (does not contribute substantially to safe contraceptive use) 1

TSH Testing (Option B)

• TSH screening is not routinely needed before contraception 1
• While oral contraceptives can affect thyroid binding proteins and alter T4 levels, they do not contraindicate contraceptive use 2, 3
• TSH is classified as Class C for contraceptive initiation 1

Transvaginal Ultrasound (Option C)

• Pelvic imaging is not required before prescribing contraception in asymptomatic women 1
• Ultrasound would only be indicated if there were symptoms suggesting pathology (abnormal bleeding, pelvic pain) 1

Endometrial Biopsy (Option D)

• Endometrial sampling is never a routine pre-contraception requirement 1
• This would only be considered in women with abnormal uterine bleeding or specific risk factors for endometrial pathology, which this patient does not have 1

Critical Clinical Pearls

Unnecessary barriers to contraceptive access: The CDC explicitly warns that unnecessary medical procedures and tests create "logistical, emotional, or economic barriers to contraceptive access," particularly for adolescents and low-income women who have high rates of unintended pregnancies 1

Quick start approach: If the provider can be reasonably certain the patient is not pregnant, contraception can be started immediately at the visit rather than waiting for next menses 1

Age considerations: At 41 years, this woman still requires contraceptive protection, as contraception is recommended until menopause or age 50-55 years 1

The Correct Answer

None of the investigations listed (A, B, C, or D) are appropriate routine pre-prescription requirements for an asymptomatic 41-year-old woman requesting contraception. 1 The only assessment that might be needed depends on which contraceptive method is selected: blood pressure for combined hormonal contraceptives, or bimanual examination for IUD insertion. 1