There is no single check that confirms polycystic ovary syndrome, or PCOS, for everyone. Clinicians combine your health history with signs, blood tests, and sometimes an ultrasound. They also consider other causes that can look similar.

The main PCOS guide gives a broad overview. This guide explains the assessment process so you can prepare questions.

What criteria are used?

In adults, a clinician commonly looks for at least two of three features after other causes have been considered:

• Ovulation that is irregular or absent, often shown by irregular periods.
• Clinical or blood-test signs of higher androgen activity.
• A polycystic ovary pattern on ultrasound or another accepted marker when suitable.

Androgens are hormones found in all people. Higher activity may be linked with coarse facial or body hair, acne, scalp hair thinning, or raised levels on a blood test.

The WHO PCOS overview explains these main features. The 2023 international PCOS guideline gives more detail on how they should be applied.

The approach differs for adolescents because irregular cycles and acne can be common during puberty. Ultrasound appearance is not used in the same way soon after periods begin.

What will the clinician ask?

Expect questions about:

• When periods began and how often they occur.
• The longest gaps between periods.
• Acne, facial or body hair, and scalp hair changes.
• Weight changes without assumptions about their cause.
• Medicines and supplements.
• Pregnancy possibility and fertility goals.
• Family history of PCOS, diabetes, or related concerns.
• Sleep, mood, and daily well-being.

The clinician may also ask about rapid changes, headaches, vision changes, nipple discharge, hot flushes, or symptoms linked with thyroid or adrenal conditions. These details help decide which other causes to check.

The guide to common PCOS signs can help you organise what you have noticed.

What may a physical exam include?

With your consent, a clinician may check blood pressure and look for acne, hair changes, or darkened skin. They may discuss weight because it can relate to some health checks, but respectful care should focus on health and your goals.

You can ask why any exam is suggested. You can request a chaperone, pause, or decline. An intimate exam is not automatically needed for every PCOS assessment.

Which blood tests may be used?

Tests depend on the history. They may include hormone levels to look for androgen activity and to consider other causes. A clinician may also check blood sugar or cholesterol because PCOS can be linked with metabolic changes.

Metabolic means processes that turn food into energy and help manage blood sugar and fats. A normal result does not make symptoms unimportant. An unexpected result should be explained in context.

Hormonal medicines can affect some results. Tell the clinician what you use and do not stop a prescribed medicine unless advised.

The ACOG PCOS guide describes blood tests and health checks that may form part of the review.

Is an ultrasound always needed?

No. If irregular ovulation and androgen signs are already present in an adult, an ultrasound may not add useful information. The decision also depends on age and current guidance.

If a scan is suggested, ask what question it will answer. A pelvic ultrasound can be done over the abdomen. An internal scan may give a clearer view in some cases, but it requires consent and may not be suitable or acceptable for everyone.

The word “polycystic” can be misleading. The scan may show many small follicles, which are fluid-filled structures where eggs develop. They are not the same as harmful ovarian cysts.

What other causes may be considered?

PCOS features overlap with several health issues. Based on the pattern, a clinician may consider:

• Pregnancy.
• Thyroid changes.
• Raised prolactin, a hormone involved in milk production.
• Some adrenal or ovarian conditions.
• Perimenopause or reduced ovarian function.
• Medicine effects.
• Changes linked with eating, exercise, stress, or another illness.

This does not mean every person needs every test. The checks should follow your history and exam.

How to prepare for the appointment

Bring a list of medicines and supplements. If possible, note several months of periods, bleeding, hair or skin changes, and key health events. The guide to tracking your menstrual cycle shows how to make a short summary.

Useful questions include:

• Which criteria apply in my case?
• What other causes are you checking?
• What will each test add?
• How could my medicines affect the results?
• Which long-term health checks are relevant to me?
• When will we review the findings?

If fertility is a goal, read PCOS and fertility and mention your timeline. Femio's clinician review process explains how our health content is checked.

When to see a doctor

Book an appointment for repeated long gaps between periods, periods that stop without a clear reason, new coarse hair growth, severe acne, scalp hair loss, or fertility concerns. Seek advice sooner for fast changes such as a deepening voice or rapidly increasing hair growth.

This page cannot tell you which criteria apply to you. A clinician can place your history and results in context.

Frequently asked questions

Can one blood test confirm PCOS?

No. Blood tests can support the assessment and check other causes, but clinicians use the whole picture.

Do I need an ultrasound?

Not always. It may add little when two other features are already clear in an adult.

Does a polycystic ovary appearance confirm PCOS?

No. A scan appearance alone is not enough.

Why might the approach differ for teenagers?

Puberty can cause cycle and skin changes that overlap with PCOS, so criteria are applied with care.