PCOS Blood Tests: What to Ask Your Doctor For

A PCOS blood test panel typically includes LH/FSH ratio, testosterone (total and free), AMH (anti-Müllerian hormone), fasting insulin, fasting glucose, DHEA-S, TSH, prolactin, and a lipid panel. No single test identifies PCOS on its own. A PCOS diagnosis requires meeting at least two of the Rotterdam Criteria: irregular ovulation, elevated androgens, or polycystic ovaries on ultrasound (ACOG, 2023).

PCOS affects an estimated 8–13% of women of reproductive age worldwide, making it one of the most common hormonal conditions in people who can become pregnant (WHO, 2023). Yet many women spend months, sometimes years, without a clear answer, partly because no single blood test can confirm PCOS on its own. This guide walks you through the essential PCOS blood test panel, what each marker means, how to read your results, and what to do next if you’re trying to conceive.

PCOS Blood Tests: Key takeaways

• PCOS cannot be confirmed by a single blood test. Diagnosis requires clinical criteria plus labs, based on the Rotterdam Criteria (ACOG).
• The essential PCOS blood test panel includes: LH/FSH ratio, testosterone (total and free), AMH, fasting insulin, fasting glucose, DHEA-S, and TSH.
• LH and FSH hormone levels are typically seen in a 2:1 or 3:1 ratio in PCOS, a key diagnostic marker.
• PCOS blood test results should always be interpreted alongside symptoms and ultrasound findings, not in isolation.
• Insulin resistance affects an estimated 35–75% of women with PCOS, making fasting insulin and glucose testing important (NIH, 2022).
• After diagnosis, tracking your LH surge with Premom may help you identify your actual fertile window despite irregular cycles.

What are the 5 signs of PCOS?

PCOS is a hormonal and metabolic condition with a wide range of symptoms. The five most commonly recognized signs include:

• Irregular or absent periods – cycles longer than 35 days, fewer than eight per year, or unpredictable in timing
• Signs of elevated androgens – excess facial or body hair (hirsutism), acne, or male-pattern hair thinning
• Polycystic ovaries on ultrasound – ovaries with 12 or more follicles measuring 2–9 mm, or ovarian volume above 10 mL
• Difficulty ovulating – irregular or absent ovulation, often the root cause of fertility challenges
• Metabolic changes – including weight changes, insulin resistance, and fatigue

According to ACOG (2023), a PCOS diagnosis requires at least two of three Rotterdam Criteria: irregular ovulation, clinical or biochemical signs of elevated androgens, and polycystic ovaries on imaging.

What blood tests are done to diagnose PCOS?

The standard PCOS blood test panel covers several areas: hormone levels, androgen markers, ovarian reserve, and metabolic health. Here is the complete lab checklist.

Essential PCOS blood tests: your complete lab checklist

PCOS blood test name: what to write on your lab request

When asking your doctor for a PCOS workup, you can request the following tests by name:

• Reproductive hormone panel: LH, FSH, total testosterone, free testosterone, DHEA-S, prolactin, estradiol
• AMH (anti-Müllerian hormone)
• Fasting insulin and fasting glucose (or HOMA-IR calculation — how hard the body is working to keep blood glucose normal)
• Lipid panel (total cholesterol, LDL, HDL, triglycerides)
• TSH (thyroid-stimulating hormone), T3, fT3 and T4
• 17-OHP (17-hydroxyprogesterone) if adrenal PCOS is suspected
• HS-CRP to monitor inflammation

Blood test for PCOS insulin resistance: fasting insulin and glucose

Insulin resistance is present in an estimated 35–80% of women with PCOS. Two tests are used to screen for insulin resistance in PCOS:

• Fasting insulin: A level above 10 mIU/L indicates the start of insulin resistance. Levels above 20 mIU/L are more strongly associated with metabolic dysfunction.
• Fasting glucose: A level at or above 100 mg/dL raises concerns for impaired glucose regulation, while a level of 126 mg/dL or higher meets the diagnostic threshold for diabetes.

Your doctor may also calculate HOMA-IR (Homeostatic Model Assessment of Insulin Resistance) using both values. A HOMA-IR above 2.5 is considered a marker of insulin resistance in the context of PCOS.

Which hormones are elevated in PCOS?

PCOS is fundamentally a hormone imbalance condition. Understanding which hormones are affected and why helps you understand your lab results.

LH and FSH hormone levels in PCOS: what the ratio means

In a typical menstrual cycle, the pituitary gland releases follicle-stimulating hormone (FSH) and luteinizing hormone (LH) in roughly equal amounts to trigger egg development and ovulation. In many people with PCOS, the pituitary produces excess LH relative to FSH. An LH:FSH ratio of 2:1 or higher is found in PCOS cases, though the ratio alone is not sufficient for diagnosis.

This imbalance disrupts follicle development, meaning eggs may begin to mature but fail to complete ovulation, which is why irregular cycles are so common. Understanding what your LH surge numbers mean can help you interpret both your lab results and your at-home ovulation test readings.

Testosterone and DHEA-S: androgens to check in PCOS

Excess androgens are one of the three Rotterdam Criteria. Both total testosterone and free testosterone may be elevated. Total testosterone above 60–70 ng/dL, or free testosterone above 2.2 pg/mL, can suggest hyperandrogenism when combined with clinical symptoms.

DHEA-S (dehydroepiandrosterone sulfate) is produced by the adrenal glands rather than the ovaries. Testing DHEA-S helps distinguish ovarian PCOS from adrenal conditions that produce similar symptoms, such as congenital adrenal hyperplasia.

AMH: what it tells you about PCOS

Anti-Müllerian hormone (AMH) is produced by the small follicles in your ovaries. Because people with PCOS tend to have a higher number of small follicles, AMH levels are often elevated and sometimes two to four times higher than typical ranges.

An AMH above 4–5 ng/mL, or higher, alongside other symptoms is increasingly used as a supportive marker for PCOS.

Estrogen and progesterone levels in PCOS

Estrogen levels in PCOS are often within or slightly above the typical range, but the pattern across the cycle is frequently disrupted. Because ovulation is irregular or absent, progesterone levels in the luteal phase are often low, which is why people with PCOS can experience anovulatory cycles where a period arrives without an egg having been released.

Tests for polycystic ovarian syndrome beyond blood work: ultrasound

A pelvic ultrasound, usually transvaginal, is part of the standard PCOS evaluation. It allows your doctor to assess:

• The number of follicles visible on each ovary (12 or more in the 2–9 mm range is a Rotterdam criterion)
• Ovarian volume (above 10 mL suggests polycystic morphology)
• Whether another condition, such as an ovarian cyst or endometriosis, may explain your symptoms

PCOS blood test results: how to read and understand them

What will bloodwork show if you have PCOS?

Not every marker will be abnormal in every person with PCOS. The condition exists on a spectrum, and your results may show only some of the following patterns:

PCOS blood test results chart: what each marker means for fertility

The hormone imbalances seen in PCOS can affect fertility in several specific ways:

• Elevated LH relative to FSH disrupts follicular development, meaning eggs may not mature properly or be released
• Elevated androgens can impair egg quality and the uterine environment
• High AMH suggests many follicles but poor follicle selection, meaning the body struggles to recruit and release a single dominant egg each cycle
• Insulin resistance suppresses sex hormone-binding globulin (SHBG), which raises free androgen levels and further disrupts the cycle
• Anovulatory cycles mean that even when a period arrives, ovulation may not have occurred

How do gynaecologists check for PCOS?

How to diagnose polycystic ovarian disease: the Rotterdam Criteria

The Rotterdam Criteria, established by consensus in 2003 and still the global standard, require two out of three of the following features for a PCOS diagnosis:

1. Oligo- or anovulation – irregular or absent ovulation, usually presenting as irregular or absent periods
2. Clinical or biochemical hyperandrogenism – either visible symptoms (hirsutism, acne, hair thinning) or elevated androgen levels on blood tests
3. Polycystic ovarian morphology on ultrasound – 12 or more follicles of 2–9 mm per ovary, or ovarian volume above 10 mL

Because PCOS is a diagnosis of exclusion, your doctor should also rule out conditions that produce similar symptoms, including thyroid dysfunction, hyperprolactinemia, congenital adrenal hyperplasia, and Cushing’s syndrome. This is why TSH, prolactin, and 17-OHP are part of the standard panel.

How to detect PCOS at home before your appointment

While only a healthcare provider can diagnose PCOS, you can document your symptoms and cycle patterns at home before your appointment:

• Track your cycle length for three to six months, noting whether cycles are consistently shorter than 21 days or longer than 35 days
• Note any physical symptoms such as new or worsening facial hair, persistent acne, or hair thinning
• Track your ovulation using ovulation prediction kits (OPKs), which identify LH surges before ovulation. However, with PCOS, you may notice multiple LH peaks due to naturally elevated or fluctuating LH levels. Pairing OPK tracking with basal body temperature (BBT) can help you identify whether a true ovulation peak actually occurred.
• Track your basal body temperature (BBT) using a BBT thermometer throughout your cycle to understand whether ovulation likely occurred. After ovulation, BBT typically rises by about 0.5–1.0°F, usually within 2–4 days after the LH peak. This temperature shift can help understand that ovulation has likely happened.
• The Premom app tracks cycle length, symptoms, cervical mucus changes, BBT, and PdG alongside LH testing. Premom’s AI photo reader scans easy@Home OPK strips and turns each strip into a numerical T/C ratio, so you can see the line progression of your LH trend rather than guessing whether a line is “positive.”

Take a PCOS self-assessment directly in the Premom app to better understand your symptoms, cycle patterns, and ovulation health.

After your PCOS blood tests: next steps for fertility

How tracking LH with Premom can help after a PCOS diagnosis

PCOS does not mean you cannot ovulate or conceive. Many people with PCOS do ovulate – just less predictably. The challenge is that standard calendar-based tracking is unreliable when cycles are irregular.

After a PCOS diagnosis, tracking your LH levels with Premom and easy@Home ovulation test strips may help you identify patterns that indicate when ovulation is approaching. Because people with PCOS can have persistently elevated LH or multiple smaller LH peaks before the true ovulatory surge, tracking LH as a numerical value over time rather than looking for a single positive test line can provide a more complete picture.

This approach may be particularly useful for people with PCOS, irregular cycles, or multiple LH peaks per cycle.

PCOS Blood Tests: Conclusion

A PCOS blood test panel helps build a clearer picture of your hormone and metabolic health. Key tests include LH, FSH, testosterone, AMH, fasting insulin, fasting glucose, DHEA-S, TSH, and a lipid panel, always interpreted alongside your symptoms and ultrasound findings.

If you’re trying to conceive, tracking your LH levels with Premom may help you identify your fertile window even with irregular cycles. You can also book a 1:1 virtual consultation with our fertility experts or explore our blog, PCOS Symptoms, Diagnosis & Fertility: Early Signs of Polycystic Ovarian Syndrome, to learn more.

Track your cycle with PCOS using Premom

Understanding whether ovulation is occurring can be an important step when trying to conceive with PCOS. Period timing alone may not always reflect what is happening hormonally. Tracking signals like LH patterns, BBT, cervical mucus, and PdG levels may help you better understand your cycle over time.

With the Premom ovulation tracker app, you can scan OPK results, log BBT, and track symptoms on a single chart. This may help you see whether your body might be approaching ovulation or has likely ovulated. For irregular cycles, Premom also offers PCOS Pro, a 6-month pass designed for more complex cycle tracking. It is a one-time purchase and does not auto-renew.

PCOS Pro includes:

• Tools for irregular cycle tracking
• Daily logs for sleep, diet, and stress
• Cycle insights that build over time
• PCOS-focused educational guidance
• Tracking LH, BBT, and PdG together

Frequently asked questions about PCOS blood tests

References

1. Christ JP, Cedars MI. Current guidelines for diagnosing PCOS. Diagnostics (Basel). 2023;13(6):1113. doi:10.3390/diagnostics13061113 https://pmc.ncbi.nlm.nih.gov/articles/PMC10047373/
2. Amisi CA. Markers of insulin resistance in Polycystic ovary syndrome women: An update. World J Diabetes. 2022;13(3):129–149. doi:10.4239/wjd.v13.i3.129 https://pmc.ncbi.nlm.nih.gov/articles/PMC8984569/
3. Sheehan MT. Polycystic ovarian syndrome: diagnosis and management. Clin Med Res. 2004;2(1):13–27. doi:10.3121/cmr.2.1.13 https://pmc.ncbi.nlm.nih.gov/articles/PMC1069067/

Disclaimer: Premom provides educational information and tracking tools. It is not medical advice. For medical guidance, consult a healthcare professional.