HA vs PCOS vs FHA: Where the Diagnostic Gray Areas Trip Coaches Up
A client comes to you with irregular cycles. She trains five days a week, eats “clean,” and isn’t underweight. Most people think: PCOS.
Meanwhile, another client has lost her period completely. She’s lean, disciplined, and consistent. Most people think: she just needs to eat a bit more.
In both cases, you might be wrong.
The reality is that hypothalamic amenorrhea (HA), functional hypothalamic amenorrhea (FHA), and PCOS don’t always present cleanly. In fact, the overlap between them is exactly where most coaches get tripped up, not because they don’t care, but because the patterns aren’t as obvious as textbooks make them seem.
Some Quick Definitions
The main distinction between FHA and HA, even though many people use the terms interchangeably, is that FHA specifically highlights that the condition is driven by lifestyle factors that are functional and reversible. HA (hypothalamic amenorrhea) is a broader umbrella term that includes FHA, but can also involve less common non-functional causes, such as structural or medical issues. PCOS is a hormonal condition characterized by androgen excess and irregular GnRH pulsatility. On paper, these seem easy to distinguish, but in practice, they often blur.
Check out the patterns:
FHA/HA:
High training (very few, if any, rest days)
Low calorie intake
Stress both physically and mentally
Loss of their cycle entirely
PCOS tends to show the following patterns:
Persistent irregularity (but periods do come)
Signs of androgen excess (acne, hair growth)
Long-term pattern, not just during stress periods
Overlapping symptoms
All three of these can result in missing or irregular periods, low progesterone, “normal” labs at certain times, and overall exhaustion. Symptoms don’t necessarily tell you the cause; they simply signal that something is off. That’s why it’s important to look at overall patterns, bloodwork, and cycle charting together.
Here’s an even more intimidating reality: sometimes a client can have more than one condition keeping them from a regular, healthy cycle. Clients often train hard, eat “clean” but not enough, sleep poorly, and carry high levels of stress. This alone can suppress ovulation and alter hormones in a way that mimics PCOS, meaning a client may have underlying PCOS that is masked by HA. Addressing HA first can help unravel whether PCOS is also present.
The “Lean PCOS” vs HA Confusion
This is one of the biggest traps coaches fall into: seeing a lean client with irregular cycles who also has slightly elevated androgens. Lean PCOS does exist; it refers to individuals who meet the criteria for PCOS but are not overweight or obese. The trap is thinking, “She’s not underweight, so it must be PCOS.” Not necessarily. Energy availability can still be low, and stress and training load still matter. You can have an HA-driven physiology with labs that resemble PCOS. This is where the confusion happens. A lean client may truly have PCOS, or they may be experiencing HA that is altering labs in a way that mimics it. Some protocols aimed at addressing PCOS can push clients further into HA, which is why symptoms often worsen and no real relief comes.
How to Avoid the Confusion
There are many common mistakes professionals make when interpreting bloodwork. Labs are often reviewed without important context, like the cycle phase or a client’s birth control history, and this can lead to inaccurate conclusions. Another mistake is over-relying on a single marker, like testosterone. While it should be acknowledged, it shouldn’t drive quick decisions; more context and more questions are needed. One of the most important things you can do is track trends over time, as relying on isolated lab results often creates more confusion than clarity. It’s also important to remember that how someone’s body looks is not your primary data point. Just because a client appears healthy or carries body fat doesn’t mean energy availability isn’t still an issue.
For You as a Coach
Your job isn’t to diagnose. As a coach, pattern recognition is key. The trend for many professionals now is to say that everything is PCOS when it clearly isn’t. Don’t underestimate the training load and stress an individual is experiencing. We aren’t here to “fix hormones”. We are here to fix the inputs.
Instead of diagnosing, teach clients to question. Is the energy they're putting in enough for what they ask of their body each day? How much recovery time do they have in relation to their training? Are their cycles irregular or completely missing? What is your history with dieting, sports, birth controls, and stress?
Prioritize getting enough food consistently, getting rid of unnecessary training loads, rest, and sleep (notice that those are marked as two separate things because they are). Help them learn to track their cycles over time instead of relying on one snapshot like bloodwork. And lastly, don’t be afraid to collaborate with a qualified medical provider to defer where needed.