Design: Emma Günther
PCOS Explained: Expert Answers on Symptoms, Diagnosis, and Care
Ask the Experts: A Q&A series with the Clue Science Team
Polycystic Ovary Syndrome (PCOS) can feel confusing, overwhelming, and is often misunderstood—but understanding it starts with the right guidance. To break down the condition, how it’s diagnosed, and the key symptoms, we spoke with Eve, Clue’s resident fertility nurse and senior reproductive health advisor, who shares her expert insights to help you take control of your health.
1. What is PCOS, and what causes it?
PCOS is a common hormonal condition that affects around 1 in 10 people with menstrual cycles. It’s a syndrome, meaning it's defined by a pattern of symptoms rather than a single cause or specific test result.
PCOS affects how the ovaries and hormones work. People with PCOS may have:
Higher levels of androgens (often called “male” hormones) can affect ovulation and cause symptoms like acne or excess hair growth
Irregular or absent ovulation, which can lead to irregular menstrual cycles
Ovaries that contain many small, immature follicles (sometimes seen on ultrasound), which is where the name “polycystic” comes from, though not everyone with PCOS has these, and they aren’t really cysts
The exact cause of PCOS isn’t fully understood, but research suggests it’s a mix of genetics, hormones, and environment.
PCOS tends to run in families, and many people with PCOS also have insulin resistance, which affects how the body processes sugar and energy.
Low-grade inflammation and environmental factors may also play a role. It’s likely a combination of these factors rather than one single cause.
2. How is PCOS diagnosed?
PCOS is usually diagnosed using the Rotterdam criteria. This is based on a mix of the features I previously mentioned:
Irregular ovulation.
Higher levels of “male” hormones like testosterone.
The presence of small “cysts” on the ovaries.
Importantly, you don’t need to have all three features to be diagnosed with PCOS. The Rotterdam criteria means that having any two of these three features can qualify for a diagnosis.
3. What are the early signs of PCOS?
Early signs of PCOS can show up in a few different ways. Some early or visible signs can include:
Irregular or missed periods
Increased facial or body hair
Thinning hair on the scalp
Acne or oily skin
Dark patches of skin on the neck or underarms (a sign of insulin resistance)
Skin tags
If these symptoms are persistent or if irregular cycles continue more than two years after your first period, it’s a good idea to reach out to a healthcare provider for evaluation.
4. How is PCOS treated?
There isn’t a cure, but PCOS is very treatable. Options depend on individual symptoms and goals:
Lifestyle changes: Eating a balanced diet, doing regular physical activity, and getting adequate sleep can help regulate insulin and hormones.
Medication: Options include birth control pills, anti-androgen medications, or insulin-sensitizing drugs like metformin.
GLP-1 medications: These were first developed for type 2 diabetes and are now used in weight management. GLP-1s are increasingly being prescribed for some people with PCOS, particularly those with insulin resistance and metabolic issues. Early research suggests they may improve weight-related symptoms and insulin sensitivity. However, they are not suitable for everyone; long-term safety data in PCOS is still limited, and they should only be used under specialist guidance. GLP-1s are not recommended during pregnancy or while trying to conceive, so anyone considering them should discuss family planning goals with their healthcare provider.
Symptom tracking: Using an app like Clue can help people monitor cycles, symptoms, and patterns to support care decisions.
Specialized treatments: These may include fertility support (such as ovulation-induction medications like letrozole or clomiphene, sometimes combined with assisted reproductive technologies) or dermatological care for skin and hair concerns.
5. One of the hallmark signs of PCOS is irregular periods. Why does PCOS cause irregular periods, and what’s considered irregular
Medically, irregular periods are defined by both cycle length and how much they vary from month to month.
According to FIGO (the International Federation of Gynecology and Obstetrics), a regular cycle lasts between 24-38 days, with no more than 7-9 days of variation between the shortest and longest cycles. Cycles are considered irregular if they are consistently shorter than 24 days, longer than 38 days, or vary widely from one cycle to the next. For example, if someone has a 25-day cycle one month and a 40-day cycle the next, that would count as irregular.
In PCOS, irregular cycles happen because of disrupted communication between the brain and ovaries. The hormonal signals that normally trigger ovulation don’t work as they should, meaning eggs aren’t released regularly. Without predictable ovulation, periods become delayed, skipped, or unpredictable altogether. This disrupted ovulation is why irregular cycles are one of the possible diagnostic features of PCOS.
6. Why does PCOS cause excess facial and body hair, and how are hormones involved?
Higher levels of androgens in PCOS stimulate hair follicles in certain parts of the body, which can lead to increased hair growth on the face, chest, or abdomen (a condition called hirsutism). These higher androgen levels can also cause thinning of hair on the scalp.
7. What causes weight gain in PCOS? Is it purely hormonal or metabolic?
Weight gain with PCOS is often linked to insulin resistance. This can cause the body to store more energy as fat, making weight harder to lose.
Hormonal imbalances, like higher androgens and disrupted ovulation, also play a role. Importantly, PCOS can affect people of all body sizes. Lean people can also have PCOS, so weight alone isn’t a reliable indicator.
8. Is PCOS often underdiagnosed, misdiagnosed, or both, and why?
Yes, PCOS is both underdiagnosed and overdiagnosed, depending on the age group and the lens through which symptoms are viewed.
Underdiagnosis is common in adults. Research shows that it can take years from the first symptoms to a confirmed diagnosis. One reason is that the “classic” picture of PCOS (irregular periods, excess hair growth, acne, and higher body weight) doesn’t reflect the full range of experiences. People who are lean, have regular cycles, or whose main struggles are with mood, fatigue, or metabolic issues may be overlooked.
Overdiagnosis is more common in teenagers. Irregular cycles are typical in the first 2-3 years after menarche, and it’s common for ovarian ultrasounds at that age to show a polycystic appearance. Diagnosing PCOS too early risks labeling what is, in many cases, a normal stage of reproductive development as a disorder. Most guidelines now recommend waiting until cycles remain irregular beyond three years post-menarche before considering a PCOS diagnosis.
Diagnostic criteria and clinical complexity add to the confusion. PCOS is understood as a complex endocrine and metabolic disorder involving high levels of androgen hormones, insulin resistance, and irregular signals between the brain and the ovaries. But not everyone with PCOS exhibits all these features in the same way. Part of the problem is that the official diagnostic criteria themselves have limitations. The most widely used system, the Rotterdam criteria, was a step forward in standardising diagnosis, but it’s not perfect. It allows for multiple combinations of features to “count” as PCOS, meaning two people with the same diagnosis can have very different symptoms.
Finally, systemic bias plays a role too. People in larger bodies or from marginalized groups are more likely to have their symptoms minimized or attributed solely to lifestyle, which can delay recognition of the underlying condition. Weight stigma can obscure underlying hormonal or metabolic issues, delaying proper diagnosis and care.
Taken together, these challenges explain why PCOS remains one of the most misunderstood conditions in women’s health. We need better awareness of its varied presentations, clearer diagnostic standards that account for age, and more investment in research to understand the hormonal and metabolic pathways behind it.
9. How do coexisting conditions like depression, anxiety, irritable bowel syndrome (IBS), or endometriosis affect the diagnosis and management of PCOS?
Coexisting conditions like depression, anxiety, IBS, or endometriosis can significantly complicate both the diagnosis and management of PCOS.
These conditions can mask or fragment symptoms, leading people to be treated for mental health struggles, digestive issues, or dermatological issues in isolation, while the underlying hormonal and metabolic aspects of PCOS remain poorly understood and often overlooked.
PCOS is one of the most common hormonal conditions worldwide, yet one of the most misunderstood. Even its name is misleading: not everyone with PCOS has ovarian cysts, and its effects go far beyond reproduction.
PCOS is often reduced to just weight changes, acne, excess hair growth, or irregular cycles. But research shows a broader picture: people with PCOS are 4–7 times more likely to experience depression or anxiety, adding an invisible but large impact on daily life.
Clue’s recent survey reinforces this reality. When asked about their most concerning cycle-related symptoms, 75% of respondents with PCOS pointed to emotional struggles, like sadness, anxiety, and mood swings, on par with tiredness (75%) and body pain (74%).
PCOS rarely exists in isolation. Nearly half of our respondents also reported other conditions: depression (38%) and anxiety (45%) were most common, but ADHD (19%), IBS or IBD (15%), and endometriosis (8%) also appeared frequently. This highlights the need for holistic, patient-centered care that looks beyond just fertility.
This complexity also complicates diagnosis. Symptoms are often scattered across specialties. One person’s symptoms may be treated as mental health struggles, another’s as digestive issues, another’s as dermatological concerns— without anyone connecting the dots. People are often bounced between gynecologists, dermatologists, psychiatrists, and gastroenterologists.
It’s little surprise, then, that more than 1 in 3 respondents told us they lived with their most troubling symptom for nine years or more before being properly diagnosed. And 57% said not being taken seriously was their biggest challenge when accessing care.
These challenges reflect wider systemic issues in women’s health. Conditions like PCOS and endometriosis are underfunded, under-researched, and too often minimized, leaving people to navigate fragmented systems and lingering stigma.
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Clue helps turn your data into a powerful tool for navigating your cycle, helping you better understand your body, and we believe data can help close this gap. By tracking cycles, symptoms, mood, and energy over time, people can build evidence of their lived experience, evidence that’s hard to dismiss in a rushed appointment. This kind of patient-led data not only empowers individuals to advocate for themselves but also helps build a more nuanced understanding of PCOS in research and care.
PCOS doesn’t look the same in everyone. And until healthcare systems reflect that diversity, too many people will keep falling through the cracks.
10. What are common myths or misconceptions about PCOS symptoms?
PCOS is surrounded by myths that can make it harder for people to get the care they deserve. Here are some of the most common misconceptions:
Myth 1: “PCOS only matters if you’re trying to get pregnant.” PCOS affects more than fertility. It can impact mental health, metabolic health, and long-term risks like cardiovascular disease and type 2 diabetes.
Myth 2: “PCOS affects everyone the same.” PCOS can affect people of all body types and with very different symptom patterns.
Myth 3: “Lifestyle changes can cure PCOS.” While lifestyle changes can help, PCOS is a lifelong condition with complex hormonal and metabolic roots. Suggesting it’s easily “fixed” puts unfair blame on patients and is factually incorrect.
Myth 4: "You need to have polycystic ovaries to have PCOS.” Despite the name, not everyone with PCOS has visible ovarian cysts on ultrasound.
Why it matters: Dispelling these myths can help reduce stigma and ensure that people get the care and validation they need.
Key takeaways
PCOS affects people in many different ways, and understanding its symptoms, causes, and dispelling any myths is key to getting the right care. As Eve highlights, raising awareness, tracking cycles, and seeking personalized support can make a real difference—because everyone deserves clarity, validation, and effective management for their health.
