How Is PMOS (PCOS) Diagnosed? And Can You Have It Without Cysts?

Medically reviewed by Meg LaFerriere, APRN · Regulate Rx, Lee’s Summit, MO

Many people assume PMOS is diagnosed by finding cysts on an ultrasound. In reality, an ultrasound is just one of three possible clues, and plenty of people are diagnosed without one.

What are the Rotterdam criteria for PMOS?

The 2023 International Evidence-based Guideline, backed by major groups including the Endocrine Society, uses the Rotterdam criteria to diagnose PMOS (formerly PCOS) in adults. You need two of these three:

1. Irregular or absent ovulation. Often seen as cycles shorter than 21 days, longer than 35 days, or fewer than 8 periods a year.
2. Androgen excess. Either clinical signs, like excess hair growth, acne or scalp thinning, or biochemical signs, meaning high androgen levels on a blood test.
3. Polycystic ovarian morphology or high AMH. Many small follicles or larger ovarian volume on ultrasound, or, in adults, an elevated anti-Müllerian hormone (AMH) blood level instead of an ultrasound.

The 2026 rename to PMOS wasn’t reported to change these criteria. If you already have both irregular cycles and clear signs of androgen excess, an ultrasound or AMH test isn’t needed to make the diagnosis.

Why do other conditions need to be ruled out?

Several conditions can cause irregular periods or high androgens and look a lot like PMOS. A diagnosis of PMOS is made only after these are considered:

• Thyroid disease (checked with TSH)
• High prolactin
• Non-classic congenital adrenal hyperplasia (checked with 17-hydroxyprogesterone)
• Pregnancy
• Low hormone signaling from the brain, often tied to under-eating, heavy exercise or stress
• Rarely, Cushing’s syndrome or an androgen-producing tumor, especially if symptoms appear quickly

Can you have PMOS without cysts?

Yes. Because only two of three criteria are needed, someone with irregular cycles and high androgens can be diagnosed with PMOS even if their ovaries look completely normal on ultrasound.

It also helps to know that the “cysts” were never really cysts. They’re immature follicles, small fluid-filled sacs that each hold an egg and paused before ovulating. That misunderstanding is one reason experts renamed the condition in 2026.

Common combination	Ultrasound needed?
Irregular ovulation + androgen excess	No
Irregular ovulation + ovarian findings or high AMH	Yes, or AMH test
Androgen excess + ovarian findings or high AMH	Yes, or AMH test

Is diagnosis different for teens?

Yes. In adolescents, the guideline advises against using ultrasound or AMH for diagnosis, because many follicles are normal in the years after periods start. Teens need both irregular cycles and androgen excess. Those with some features may be considered “at risk” and rechecked later.

What does a PMOS evaluation usually include?

Expect a detailed health and cycle history, a physical exam that looks at skin and hair, blood tests for hormones and to rule out look-alikes, and often metabolic labs such as a glucose test and lipid panel. If you take hormonal birth control, your clinician may discuss how it affects hormone test results.

At Regulate Rx in Lee’s Summit, our women’s hormone program can evaluate hormones and metabolic labs and coordinate with your OB-GYN or primary care clinician. Our initial lab panel is $150, as listed on our pricing page.

Frequently asked questions

Is there one blood test for PMOS?

No single test confirms PMOS. Diagnosis comes from combining your cycle history, physical signs, hormone labs and sometimes an ultrasound or AMH test, after other causes are ruled out.

Can I be tested for PMOS while on birth control?

Hormonal birth control lowers androgen levels and regulates bleeding, which can mask PMOS features. Your clinician may suggest timing labs off hormones, but don’t stop birth control without a plan in place to prevent pregnancy.

Why was I told I have cysts but not PMOS?

Many small follicles on an ultrasound can be normal, especially in younger people. Without a second feature, like irregular ovulation or androgen excess, that finding alone doesn’t mean PMOS.

Sources: 2023 International Evidence-based Guideline for the Assessment and Management of PCOS; The Lancet, 2026; Endocrine Society; American College of Obstetricians and Gynecologists; Cleveland Clinic.

This article is for general education and isn’t medical advice. Treatments aren’t right for everyone, and results vary. Our practitioner reviews your health history before any treatment.