Making Sense of Your PMOS Labs

Most people I work with get their PMOS labs back before anyone has explained what the tests were for. They end up scrolling through flagged numbers in a patient portal late at night, trying to piece it together. If that's where you are, I want to walk you through the labs you're likely to see and what each one is actually for.

A quick note on the name first. In May 2026, polycystic ovary syndrome (PCOS) was officially renamed polyendocrine metabolic ovarian syndrome (PMOS). Same condition, new name. I'm glad for the change, because the old name put the focus on "cysts" when this is really a hormonal and metabolic condition that touches the whole body. You'll probably see both names for a while.

PMOS labs generally do one of three things: look for signs of PMOS itself, rule out conditions that can look similar, or check on your metabolic health. I'll go through them in that order.

How PMOS is diagnosed

There's no single blood test that gives a yes or no. In adults, a diagnosis needs two of these three:

1.     Irregular or absent periods, which usually means ovulation isn't happening regularly

2.     Higher androgens, seen either in symptoms like extra hair growth, acne, or hair thinning, or in bloodwork

3.     Polycystic-appearing ovaries on ultrasound, or a high AMH level as an alternative

Other conditions with similar symptoms need to be ruled out too. Labs cover part of this, but your history and symptoms matter just as much. [Your voice: optional line about clients who were told they have PMOS based on an ultrasound alone.]

Labs that look for higher androgens

Androgens are hormones like testosterone and DHEA. Everyone makes them, and in PMOS they tend to run high. Your doctor will usually start with total and free testosterone. Free testosterone is the part that's active in your body, and it's often calculated using SHBG, a protein that binds testosterone and keeps it inactive. If those come back normal but high androgens are still suspected, androstenedione and DHEAS (the form of DHEA usually measured in blood) may be added.

Two things I always want people to know here. Hormonal birth control lowers androgens, so labs drawn while you're on it can look normal even if you have PMOS. If the diagnosis is still uncertain, your doctor may suggest coming off it for about three months before testing. And normal androgen labs don't rule PMOS out, since symptoms like extra hair growth count on their own.

You may also see AMH, short for anti-Müllerian hormone. AMH is made by the small follicles in your ovaries, the tiny fluid-filled sacs that each hold an immature egg. People with PMOS often have more of these small follicles, so their AMH tends to run higher. Because of that, a high AMH level can now be used in place of an ultrasound for adults as one of the diagnostic criteria. You may also hear AMH described as an "egg count" or a fertility test. It does roughly reflect how many follicles you have, but it can't tell you whether you'll be able to get pregnant.

Labs that rule out other causes

Irregular periods and high androgens can come from several places, so part of the workup is making sure something else isn't going on. You might see:

•      TSH to check your thyroid

•      Prolactin, a hormone that can disrupt cycles when it's high

•      17-hydroxyprogesterone to screen for non-classic congenital adrenal hyperplasia, an adrenal condition that can look a lot like PMOS

•      A pregnancy test

•      FSH, LH, and estradiol to look for other reasons periods might stop, such as the ovaries slowing down early or the brain pausing cycles in response to undereating, intense exercise, or stress

The LH to FSH ratio used to get a lot of attention, but it isn't part of how PMOS is diagnosed. If your periods are coming at all, some of these labs are timed to the first few days of your cycle.

Labs that check your metabolic health

These don't diagnose PMOS. They look at how your body is handling blood sugar and cholesterol, since PMOS can raise the risk of diabetes and heart disease over time. Current guidelines say everyone with PMOS should have their blood sugar checked at diagnosis, in every body size, and then every one to three years.

The most accurate test is an oral glucose tolerance test. You drink a sugary solution and have your blood sugar checked before and two hours after. Fasting glucose or hemoglobin A1c are simpler options. You'll likely also get a lipid panel and have your blood pressure checked.

Then there's fasting insulin, which I think is one of the most useful numbers to ask for. Insulin often starts rising years before blood sugar does. A fasting insulin level, sometimes paired with fasting glucose to calculate something called HOMA-IR, can show insulin resistance early, while there's plenty of room to make changes. It isn't part of the standard guideline screening yet, partly because insulin tests aren't standardized across labs and there's no universal cutoff for "high." So I like to look at it alongside glucose and A1c, and to recheck with the same lab over time rather than reading too much into one result.

If you take metformin, ask about checking your vitamin B12 every so often, since metformin can lower it.

Keeping the numbers in perspective

Lab results are information about what's happening in your body right now. That's it.

Insulin resistance shows up in people of every size, so a flagged result isn't a judgment on you. A lot of people are told weight loss is the main treatment. What actually moves these numbers is eating regularly and eating enough, sleep, stress, movement you can keep up with, and medication when it's needed. Those help whether or not your weight changes.

Where I see people run into trouble is cutting way back on food right after a diagnosis. That can make cycles more irregular, and it usually turns into a pattern of restricting and then overeating that leaves people feeling worse. Long stretches without eating can also make blood sugar swings and cravings stronger, which is the opposite of what most people are hoping for. What tends to help more is eating regularly throughout the day, with meals and snacks that actually satisfy you.

Questions to bring to your doctor

•      Which of these labs were for diagnosis, and which were for my metabolic health?

•      Was I on hormonal birth control when my labs were drawn? Does that change how we read them?

•      Which results are outside the lab's range, and what do they mean together?

•      When should we recheck, and which tests?

•      Should I be seeing anyone else, like an endocrinologist or a dietitian?

If you're newly diagnosed and want help eating in a way that supports your PMOS without feeling too restrictive, this is exactly the work I do at Nourished Nutrition Therapy.

This post is for general education and isn't medical advice. Please talk with your healthcare provider about your own lab results and care.