What hormonal tests are recommended for a patient with a missed period?

Recommended Hormonal Tests for Missed Period

For patients with a missed period, the recommended hormonal tests include pregnancy test, FSH, LH, prolactin, thyroid function tests (TSH, T4), and progesterone levels during the mid-luteal phase. 1

Initial Testing Algorithm

• Pregnancy test - must be performed first to rule out pregnancy as the most common cause of missed periods 2, 3
• FSH and LH levels - should be measured between days 3-6 of the menstrual cycle, with three estimations taken 20 minutes apart for accurate assessment 1
• Prolactin measurement - essential to rule out hyperprolactinemia, which is a common cause of menstrual irregularity 1, 4
• Thyroid function tests (TSH, T4) - necessary to exclude thyroid dysfunction that frequently presents with menstrual irregularities 1, 4
• Estradiol levels - should be measured during the early follicular phase to establish baseline ovarian function 1
• Progesterone levels - should be measured during the mid-luteal phase (approximately day 21 of a 28-day cycle) to confirm ovulation; levels <6 nmol/l indicate anovulation 1

Additional Tests Based on Clinical Presentation

• Testosterone levels - should be checked if signs of hyperandrogenism (hirsutism, acne) are present 1
• Androstenedione measurement - indicated when testosterone is elevated to rule out adrenal/ovarian tumors 1
• DHEAS (dehydroepiandrosterone sulfate) - should be measured if non-classical congenital adrenal hyperplasia is suspected 1
• Fasting glucose and insulin levels - recommended if metabolic disorders or PCOS are suspected 1
• Anti-Müllerian hormone (AMH) - may provide additional information on ovarian reserve, particularly in younger women 1

Progesterone Challenge Test

• A progesterone challenge test should be performed to determine outflow tract patency and estrogen status if serum prolactin and TSH levels are normal 5, 6
• This test helps differentiate between:
  • Hypoestrogenic amenorrhea (negative challenge test) 5
  • Adequate estrogen levels with progesterone deficiency (positive challenge test) 5, 6

Timing Considerations

• Laboratory tests should be performed without hormonal contraception for accurate assessment 1
• For women with irregular cycles, testing should still aim for days 3-6 of the cycle when possible 1
• A single FSH measurement is not diagnostic as levels fluctuate significantly during perimenopause 1

Common Pitfalls to Avoid

• Relying on a single FSH measurement for diagnosis 1
• Measuring hormone levels at incorrect times during the menstrual cycle 1
• Failing to consider non-reproductive causes of menstrual irregularity such as thyroid disorders 1, 4
• Not accounting for the effects of medications, stress, or weight changes on hormone levels 1
• Forgetting to rule out pregnancy before proceeding with diagnostic evaluation 3, 5

Special Considerations

• Pregnancy testing should be considered in cases of missed menses (unless using etonorgestrel implants or depot medroxyprogesterone acetate) 2
• Patients with hypothalamic amenorrhea should be evaluated for eating disorders and are at risk for decreased bone density 3
• Patients with polycystic ovary syndrome are at risk for glucose intolerance, dyslipidemia, and other aspects of metabolic syndrome 3
• Normal ranges for hormones vary by laboratory; interpretation should be based on the specific reference ranges provided 1