How Is PCOS (PMOS) Diagnosed?

• How is PCOS diagnosed involves assessing your symptoms, history and relevant clinical findings rather than relying on one test.
• The Rotterdam criteria require two of three features after other possible causes have been considered.
• Blood tests, physical examination, and ultrasound can each provide different information during a PCOS assessment.
• Our free PMOS PCOS quiz test can help you explore how closely your symptoms match common patterns, but it cannot diagnose the condition.
• In the UK, you can usually start the diagnostic process with your GP without necessarily needing a specialist referral.

How Is PCOS Diagnosed? The Short Answer

PCOS is diagnosed by a qualified healthcare professional using the Rotterdam criteria, with at least two of three criteria needing to be met after other possible causes have been ruled out. There is no single test that confirms PCOS, so if you’re wondering how is PCOS diagnosed or how to diagnose PCOS, it’s about putting the wider clinical picture together rather than relying on one symptom, blood result, or scan.

You may already have read about the different signs and tests used when investigating PCOS. The important point is that having one of these features does not automatically mean you have PCOS. A clinician needs to assess your individual situation and confirm whether the diagnostic criteria are met, while also considering other possible explanations for your symptoms.

The sections below explain what those criteria involve, which tests may be used, and what the diagnostic process can look like.

Three Criteria Doctors Look For

The Rotterdam criteria give your clinician a framework for diagnosing PCOS. Two of the three following criteria must be met for a PCOS diagnosis. Having just one on its own is not enough to diagnose PCOS, and it does not mean that you have the condition.

Irregular or Absent Periods

One of the criteria relates to whether you are ovulating regularly. Anovulation, meaning your ovaries are not releasing an egg regularly, can lead to periods that are very far apart, unpredictable, or absent.

You may already know that irregular periods are commonly associated with PCOS, but they can happen for many other reasons too. When it comes to PCOS, how to diagnose the condition depends on your usual cycle pattern and medical history rather than treating one unusually early or late period as evidence of PCOS.

If your periods have become less predictable, it can be useful to keep track of your cycle before your appointment. That gives your clinician a clearer picture of what has been happening over time.

Signs of Raised Androgens

Another criterion involves androgens, hormones such as testosterone that are naturally present in everyone. With PCOS, you may have higher-than-expected androgen levels or physical signs that your body is being affected by them. This is sometimes called hyperandrogenism, meaning raised androgen levels or signs of increased androgen activity.

You might notice signs such as increased facial or body hair, acne, or scalp hair thinning. Your clinician may also look at blood-test results when assessing androgen levels. You do not necessarily need to have both physical signs and abnormal blood results for this criterion to be considered.

Polycystic Ovaries on a Scan

The third criterion concerns how your ovaries appear on an ultrasound. A scan may show a greater number of small follicles, fluid-filled structures in the ovaries where eggs develop, or increased ovarian volume.

Despite the name, these are not the same as ovarian cysts. You can have ovaries with this appearance without having PCOS, and you do not necessarily need this finding to receive a diagnosis.

That is why the diagnosis of PCOS criteria cannot be reduced to an ultrasound result. Your clinician looks at the relevant findings together and decides whether the criteria are met after other possible explanations have been considered.

What Tests Are Used?

As already mentioned, there is no single test for PCOS. If you’re wondering how do they test for PCOS, your clinician may use a combination of blood tests, a physical examination and, when appropriate, a pelvic ultrasound to build a clearer picture of what is happening and check for other possible causes of your symptoms.

You may already have come across tests such as testosterone, LH, FSH or AMH while researching PCOS. The important thing to know is that they do not all serve the same purpose. Some can provide information relevant to PCOS, while others are mainly used to rule out conditions that can cause similar symptoms or menstrual changes.

Blood Tests

If your clinician orders blood tests, the results can help answer different questions rather than simply looking for a single “PCOS level.” Testosterone and SHBG can help assess androgen levels, for example, while LH and FSH may provide additional context about your reproductive hormones.

Other tests are often included because something else could explain the symptoms you’re experiencing. Prolactin can help investigate raised prolactin as a cause of menstrual changes, while thyroid function tests can help identify thyroid problems with similar symptoms. AMH may provide information about the number of follicles in your ovaries, but it should not be treated as a standalone way to diagnose PCOS.

You may also be offered fasting glucose or HbA1c. These tests look at blood sugar rather than diagnosing PCOS itself and can help your clinician assess metabolic health.

You won't necessarily need every test listed. The tests your clinician chooses will depend on your symptoms, medical history and individual circumstances.

Ultrasound

A pelvic ultrasound gives your clinician a closer look at your ovaries. It may show a higher number of follicles or increased ovarian volume, creating an appearance sometimes associated with PCOS.

If you've seen the term “polycystic ovaries” above, it is worth knowing that this does not mean you have ovarian cysts, nor does the ultrasound finding alone answers the question of how do they diagnose PCOS.

Physical Examination

Your clinician may also look for physical signs that provide more context, such as increased facial or body hair, acne or scalp hair thinning. Depending on your circumstances, they may also check your blood pressure or weight.

Once again, these checks cannot diagnose PCOS on their own. Instead, they help your clinician understand your symptoms and decide whether further investigation is needed.

It is also important to remember that some tests used during a PCOS assessment are intended to rule out other conditions rather than confirm PCOS. This can make the seemingly long list of tests easier to understand: your clinician is looking at your individual picture rather than searching for one specific PCOS result.

How Do You Get Diagnosed with PCOS in the UK?

In case you're wondering how to get diagnosed with PCOS in the UK, the usual starting point is your GP. You don't necessarily need to see a specialist: many people can be assessed and diagnosed in primary care, with referral to a gynecologist or endocrinologist when the diagnosis is unclear or specialist input is needed.

The process isn't always a fixed step-by-step journey, as not every part will be necessary for you. What happens next can depend on your symptoms and what your initial assessment shows:

1. GP consultation. Your GP will ask about your menstrual history, symptoms and medical history and may carry out a physical examination. If you've been keeping track of your periods or symptoms, bringing that information with you can make the appointment more useful.
2. Blood tests. You may be offered hormone and other blood tests to help investigate what's causing your symptoms and rule out conditions that can look similar to PCOS.
3. Possible ultrasound. You may be offered a pelvic ultrasound to examine your ovaries, but you don't necessarily need one to receive a PCOS diagnosis. If the other relevant criteria are already met, a scan may not add much to the diagnosis.
4. Specialist consultation if needed. Your GP may refer you to a gynecologist or endocrinologist when the diagnosis is uncertain, your symptoms are more complex, or specialist input is needed.

How Can You Prepare for Your GP Appointment?

You don't need to arrive with your own diagnosis. However, it can help to bring information that gives your GP a clearer picture of what's been happening. You might note:

• when your periods occurred and how regular they have been;
• symptoms you've noticed and when they started;
• previous blood-test or scan results;
• medications and supplements you're taking;
• relevant family or medical history;
• questions you want to ask during the appointment.

This can be particularly useful if you've already spent time researching PCOS and have a lot of information to work through.

How Long Does It Take?

There is no set timeframe for a PCOS diagnosis. If your GP can complete the assessment and investigations in primary care, the process may take only a couple of appointments. If you need further investigations or a specialist referral, it can take longer. NHS waiting times also vary depending on where you live and which services are available.

With private healthcare, you may be able to arrange appointments and investigations more directly, but you'll need to pay for the consultations and tests yourself.

As a wrap-up, if you're asking how do gynecologists check for PCOS, they use much the same overall information: your symptoms and medical history, relevant examination and test results, and an ultrasound when appropriate.

Who diagnoses PCOS? It can be a GP or an appropriate specialist; you don't necessarily need to see a specialist to receive a diagnosis.

Why PCOS Is Often Missed or Diagnosed Late

The question to add context here - is PCOS hard to diagnose? It can be. There is no single test that confirms it, and the symptoms can overlap with those of other conditions.

This can make diagnosis more difficult, particularly when symptoms develop gradually or change over time.

Symptoms May Overlap with Other Conditions

Irregular periods, acne, increased facial or body hair, scalp hair thinning and weight changes are commonly associated with PCOS, but they are not specific to it. Thyroid disorders and other hormonal conditions can cause similar symptoms, so your clinician needs to consider the wider picture.

Symptoms May Be Dismissed

Some people have symptoms that are attributed to stress, lifestyle factors or normal changes in their menstrual cycle before PCOS is considered. If you've noticed changes in your periods or developed new symptoms, discussing them with your GP can help make sure they're properly assessed.

There Is No One Particular Body Type for PCOS

PCOS can affect people across different body sizes. The assumption that it only affects people who are overweight can contribute to missed or delayed diagnoses.

So, when is PCOS usually diagnosed? It may be diagnosed during the teenage years or adulthood, depending on when symptoms appear and when someone seeks medical assessment. A later diagnosis does not make your symptoms any less real.

Can You Test for PCOS at Home?

To readers wondering “How do I check for PCOS at home?”: you can check some hormones using an at-home test, but the result cannot diagnose PCOS. It may give you information to discuss with your GP, but it cannot show whether you meet the diagnostic criteria.

You may have come across home kits that measure markers such as testosterone. However, PCOS is not diagnosed from hormone levels alone. Your clinician will also consider your menstrual history, symptoms and, when appropriate, an ultrasound or other investigations.

If you use an at-home test, take the result to your GP as additional information. They can interpret it alongside your symptoms and decide whether further assessment is needed.

A normal result does not necessarily rule out PCOS, while an abnormal result does not confirm it. Getting tested for PCOS still requires your results and wider symptoms to be assessed by a qualified healthcare professional.

What Happens After a PCOS Diagnosis?

Getting a PCOS diagnosis can bring some relief because you finally have an explanation for symptoms you may have been trying to understand for a long time. What happens next depends on your symptoms, priorities and circumstances, but your healthcare team can help you decide what support makes sense for you.

This may include lifestyle guidance around nutrition and physical activity, medication for specific symptoms, and ongoing monitoring of areas such as blood sugar and cardiovascular health. If your symptoms or priorities change, for example, if you start planning a pregnancy, your care can be reviewed.

Some people also choose to include a food supplement as part of their wider diet and lifestyle routine to support areas they may be working on after a PCOS diagnosis, such as cravings and everyday energy. For a convenient way to include several nutritional ingredients in one daily serving, Orbelli Hormonal Balance for Women combines myo-inositol, D-chiro-inositol, vitamin B6, folate and zinc. It is a food supplement, not a treatment or cure for PCOS, and it should not replace medication, dietary advice or care recommended by your healthcare professional.

The big takeaway is that there is no single approach that works for everyone with PCOS. How do you diagnose PCOS is only one part of the wider picture; your follow-up care can be adjusted over time based on how you're feeling, what you want to manage and what you and your clinician decide is appropriate.

Frequently Asked Questions

How long does it take to get diagnosed with PCOS?

There is no fixed timeline, but many women in the UK describe waiting several months between first raising symptoms with a GP and receiving a confirmed diagnosis. Blood tests are usually arranged relatively quickly, while ultrasound appointments and specialist referrals can add to the wait. The speed of how PCOS is diagnosed varies depending on your area, healthcare provider and whether specialist input is needed.

Can you have PCOS with regular periods?

Yes. Having regular periods does not rule it out. Due to how is PCOS detected (two of the three Rotterdam criteria need to be met), you could still receive a diagnosis if you have signs of raised androgens and polycystic ovaries on an ultrasound, after other possible causes have been ruled out.

Do you need an ultrasound to diagnose PCOS?

Not always. How to be diagnosed with PCOS does not depend on an ultrasound in every case. If you have clear evidence of irregular ovulation and raised androgens, you may already meet two of the three Rotterdam criteria, so an ultrasound may not be needed for diagnosis. A scan can be useful when the picture is less clear or your clinician needs to investigate other possible causes.

What blood tests are used for PCOS?

No blood test confirms PCOS on its own. How do doctors diagnose PCOS involves looking at blood-test results alongside your symptoms, menstrual history and other findings. Blood tests may measure testosterone, SHBG, LH, FSH and AMH, while thyroid, prolactin and glucose tests can help rule out other conditions with similar symptoms.

Can I get pregnant with PCOS?

Yes. Many women with PCOS become pregnant naturally or with medical support. Because irregular ovulation is one of the diagnostic criteria when you figure out how to get a PCOS diagnosis, your cycles may be harder to predict, which can make timing conception more difficult. For more on fertility, ovulation and PCOS and pregnancy, including what support may be available when you're trying to conceive, see our guide.

Can PCOS go away?

PCOS is generally considered a long-term condition, but your symptoms can change over time. Understanding what is PCOS diagnosis can help you make sense of your symptoms, while cycle regularity, androgen-related symptoms and metabolic health may improve with appropriate lifestyle changes and medical support. For example, for practical advice on nutrition, exercise, sleep and stress, our PCOS weight loss guide covers sustainable lifestyle habits in more detail. Your symptoms may also change at different stages of life.

Research & Clinical Sources

Interested in exploring the research yourself? Below you'll find the key clinical guidelines, UK healthcare resources and patient information that informed this article.

Clinical Guidelines

• 2023 International Evidence-Based Guideline for the Assessment and Management of Polycystic Ovary Syndrome
• NICE Clinical Knowledge Summary: Polycystic Ovary Syndrome

UK Healthcare Information

• NHS: Polyendocrine Metabolic Ovarian Syndrome (PMOS)
• NHS Wales: Polycystic Ovary Syndrome — Diagnosis

Patient Information

• Verity: Diagnosing PCOS
• Verity: Evidence-Based PCOS Booklets