What are the diagnostic tests and procedures for Polycystic Ovary Syndrome (PCOS)?

From the Guidelines

Diagnosing Polycystic Ovary Syndrome (PCOS) involves a combination of clinical evaluation, laboratory tests, and imaging studies, with the most recent evidence suggesting the use of total testosterone (TT), free testosterone (FT), and free androgen index (FAI) as first-line laboratory tests to assess biochemical hyperandrogenism. The diagnostic process usually begins with a thorough medical history and physical examination to identify common symptoms like irregular periods, excess hair growth, acne, and weight gain. Laboratory tests are essential and include hormone level assessments such as testosterone, free testosterone, DHEAS, androstenedione, LH, FSH, estradiol, and prolactin 1. The LH to FSH ratio is often elevated in PCOS patients. Metabolic evaluations are also important, including fasting glucose, insulin levels, lipid profile, and an oral glucose tolerance test to check for insulin resistance and diabetes risk. Thyroid function tests (TSH, T3, T4) help rule out thyroid disorders that can mimic PCOS symptoms.

Some key points to consider in the diagnosis of PCOS include:

• The use of liquid chromatography-tandem mass spectrometry (LC-MS/MS) for assessing biochemical hyperandrogenism, particularly for TT, DHEAS, and A4, as it provides high accuracy 1
• The calculation of free testosterone (FT) by equilibrium dialysis or ammonium sulfate precipitation, or by using the free androgen index (FAI) 1
• The consideration of measuring A4 and DHEAS if TT or FT are not elevated, although these have poorer specificity 1
• The importance of transvaginal ultrasound in visualizing the ovaries and identifying the characteristic polycystic appearance, with a threshold of 25 follicles, 10 mL of ovarian volume, or both, as recommended by the Androgen Excess and Polycystic Ovary Syndrome Society 1

For diagnosis, most clinicians follow the Rotterdam criteria, which require at least two of three features: oligo/anovulation, clinical or biochemical hyperandrogenism, and polycystic ovaries on ultrasound. Additional tests may be ordered based on individual presentation, such as 17-hydroxyprogesterone to rule out congenital adrenal hyperplasia or cortisol tests to exclude Cushing's syndrome. Early diagnosis is crucial as PCOS increases the risk of infertility, metabolic syndrome, type 2 diabetes, and cardiovascular disease.

From the Research

Diagnostic Tests for PCOS

To diagnose Polycystic Ovary Syndrome (PCOS), several tests and procedures can be used, including:

• Pelvic ultrasound to examine the ovaries and detect any cysts or other abnormalities 2
• Hormonal tests to measure levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone 2, 3
• Biochemical tests to assess lipid profiles, fasting glucose, and insulin levels 2
• Physical examination to check for signs of hyperandrogenism, such as acne, hirsutism, and male pattern baldness

Ultrasound Features of PCOS

Ultrasound features of polycystic ovaries can relate to the degree of reproductive and metabolic disturbance in PCOS, including:

• Antral follicle count (AFC) and ovarian volume (OV) 3
• Follicle distribution pattern, stromal area, and ovarian area 3
• Stromal to ovarian area ratio (S/A) and stromal echogenicity index (SI) 3
• Presence of multiple follicles (> 5) on ultrasound, which was found in 82% of adolescent and 88% of adult PCOS patients 2

Hormonal and Biochemical Parameters

Hormonal and biochemical parameters that can be used to diagnose PCOS include:

• LH/FSH ratio, which was significantly higher in PCOS patients compared to controls 2
• Free testosterone level, which was also significantly higher in PCOS patients compared to controls 2
• Lipid profile and fasting glucose/insulin ratio, which can be used to assess metabolic dysfunction in PCOS 2, 3