What blood tests are recommended for Polycystic Ovary Syndrome (PCOS) diagnosis?

From the Guidelines

Blood tests for diagnosing Polycystic Ovary Syndrome (PCOS) should include total testosterone (TT) and free testosterone (FT) as the first-line laboratory tests to assess biochemical hyperandrogenism, as recommended by the 2023 International PCOS Guideline 1. The diagnosis of PCOS requires a comprehensive approach, considering clinical, biochemical, and ultrasound findings.

• The recommended panel of blood tests includes:
  • Hormone levels: TT, FT, luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin, and thyroid-stimulating hormone (TSH)
  • Metabolic markers: fasting glucose, HbA1c, insulin levels, and a lipid profile
  • Androgen measurement: androstenedione (A4) and dehydroepiandrosterone sulfate (DHEAS) can be considered if TT or FT are not elevated These tests help identify hormonal imbalances characteristic of PCOS, such as elevated testosterone and LH:FSH ratio, while also screening for common metabolic complications like insulin resistance and dyslipidemia. It is essential to note that the accuracy of androgen measurement can vary depending on the method used, with liquid chromatography with tandem mass spectrometry (LC-MS/MS) being the most accurate method 1. Testing for other conditions with similar symptoms, such as thyroid disorders or hyperprolactinemia, is crucial to rule out alternative diagnoses. The 2023 International PCOS Guideline recommendations should be followed, which emphasize the importance of using TT and FT as the primary laboratory tests for assessing biochemical hyperandrogenism in PCOS diagnosis 1.

From the Research

Blood Tests for PCOS

• The diagnosis of Polycystic Ovary Syndrome (PCOS) is based on the presence of two of the following three conditions: oligo- and/or anovulation, clinical and/or biochemical signs of hyperandrogenism, and polycystic ovaries, as well as the exclusion of other aetiologies 2.
• Blood tests may be used to screen for associated endocrine abnormalities, such as insulin resistance, impaired glucose tolerance, and type 2 diabetes mellitus 2, 3.
• The following blood tests may be used to diagnose and monitor PCOS:
  • Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels to evaluate ovulatory function 4
  • Anti-Müllerian hormone (AMH) levels to assess ovarian function and predict PCOS 4
  • Testosterone levels to evaluate hyperandrogenism 4
  • Prolactin levels to rule out other endocrine disorders 4
• A study found that AMH had the largest operating characteristic curve for diagnosing PCOS, followed by LH:FSH ratio and testosterone levels 4.

Diagnostic Criteria

• The Rotterdam criteria are commonly used to diagnose PCOS, which require the presence of two of the following three findings: hyperandrogenism, ovulatory dysfunction, and polycystic ovaries, plus the exclusion of other diagnoses that could result in hyperandrogenism or ovulatory dysfunction 5.
• The Endocrine Society recommends using the Rotterdam criteria for diagnosis, and it is reasonable to delay evaluation for PCOS in adolescent patients until two years after menarche 5.

Treatment and Management

• Treatment of PCOS is individualized based on the patient's presentation and desire for pregnancy, and may include lifestyle modifications, such as weight loss, and pharmacological treatments, such as clomiphene and metformin 2, 5.
• Hormonal contraceptives may be used to regulate menstrual cycles and improve hyperandrogenism symptoms 5, 6.
• Metformin may be used to improve insulin sensitivity and reduce the risk of type 2 diabetes mellitus 5.