Tag: PMOS

Polyendocrine metabolic ovarian syndrome (PMOS) is the condition you may still know as polycystic ovary syndrome (PCOS). It’s one of the most common hormonal conditions, affecting around 1 in 8 women. But despite the old name, it has never been just about the ovaries. PMOS can affect your periods, ovulation, skin, hair, metabolism, fertility, sleep and mental health. It can also look completely different from one person to another. One person may have very irregular periods and excess facial hair, while another has acne, fairly regular cycles and no obvious symptoms until they start trying to conceive. That variation is one of the reasons PMOS can be difficult to recognise and why diagnosis is sometimes delayed. Whether you have recently been diagnosed, think your symptoms could be linked to PMOS, or have been living with the condition for years, this guide covers PCOS symptoms, diagnosis, fertility, treatment, nutrition and long-term health. Quick facts:  If you are wondering whether your symptoms could be linked to PCOS, Hertility’s Advanced Hormone and Fertility Test can help build a clearer picture of your hormones, cycle and symptoms to help you understand what’s going on. Why was PCOS renamed PMOS? On 12 May 2026, the international PCOS community officially adopted the name polyendocrine metabolic ovarian syndrome, or PMOS. The previous name, polycystic ovary syndrome, could be misleading for several reasons. Firstly, the “cysts” associated with PCOS are not typical ovarian cysts. They are usually small ovarian follicles containing immature eggs. Secondly, you can have the condition without having polycystic-looking ovaries at all. Most importantly, the old name placed the emphasis on the ovaries when the condition can affect much more than reproductive health, including metabolism, hormones, mental wellbeing and long-term health. The new name was developed through an international process involving healthcare professionals, researchers and people living with the condition. If you already have a PCOS diagnosis, you do not need to be diagnosed again. Your diagnosis has not changed. You will also continue to see the term PCOS in medical records, research and online searches, which is why we use both PCOS and PMOS throughout this guide. Read more: PCOS has been renamed PMOS — here’s what that means for you. How common is PCOS? The World Health Organization estimates that PMOS affects up to 13% of women of reproductive age, making it one of the most common hormonal conditions worldwide, and that up to 70% of those affected may not know they have it. In the UK, the NHS estimates it affects about 1 in every 10 women. Part of the problem is that there’s no single way it presents. Diagnosis can also take time. In one international study, over a third of people with PCOS waited more than two years for a diagnosis, and almost half saw three or more health professionals before getting one. What are the common symptoms of PCOS? PCOS symptoms can affect your menstrual cycle, skin, hair, metabolism, sleep, mood and fertility. You do not need to have every symptom to have the condition. Menstrual cycle-related symptoms One of the most common features is irregular ovulation. which can make periods longer, unpredictable or absent for months, sometimes with heavier or prolonged bleeding after a long gap.  You may ovulate later, less often, or not at all in some cycles (an anovulatory cycle). In adults more than three years past their first period, cycles shorter than 21 days, longer than 35 days, or fewer than eight a year are considered irregular. Having regular periods don’t completely rule out PCOS, though more on that below.  If you want to understand your own cycle, see our guide Menstrual Cycle 101: Your Complete Guide to How Your Cycle Works Skin and hair-related symptoms Higher androgen activity (androgens include hormones like testosterone) can contribute to acne, oily skin, excess facial or body hair (known as hirsutism), often on the chin, upper lip, chest, abdomen or back, and scalp hair thinning, often noticed as a widening parting.  Hair-growth patterns vary a lot between individuals and ethnic groups, which matters when symptoms are assessed. Some people also develop acanthosis nigricans, darker, thicker, velvety-looking skin around the neck or underarms, which can be linked to insulin resistance. To find out more about how hormones affect your skin, read our guide to skin and hair changes. Weight gain or difficulty losing weight Some people experience weight gain or find weight harder to manage, but you don’t need to be overweight to have PCOS. It affects people across all body sizes, and insulin resistance can occur in people who aren’t overweight. Fatigue and sleep problems Significant tiredness is common, although fatigue has many causes and shouldn’t automatically be blamed on hormones. Obstructive sleep apnoea is more common in PMOS, even after taking BMI into account. So if you snore, wake up unrefreshed or feel tired all day, it’s worth talking to a healthcare professional. Mental health-related symptoms PCOS isn’t only physical. Depression and anxiety are more common, and symptoms like acne, unwanted hair growth, fertility difficulties, body-image concerns and weight stigma can all affect quality of life. Current guidance recommends that psychological wellbeing forms part of PMOS care, including screening and support for depression, anxiety and eating disorders. Difficulty conceiving PCOS is a leading cause of irregular ovulation and anovulatory infertility. If ovulation happens less often, there are fewer chances for egg and sperm to meet. But that’s very different from saying everyone with PCOS is infertile; many conceive naturally, and effective treatments exist when ovulation needs support. What causes PCOS? There is no single known cause of PCOS. Instead, it appears to develop through a combination of genetics, hormone signalling, ovarian function, metabolism and environmental factors. Two factors that are particularly important are androgens and insulin. High levels of Androgens Androgens are a group of hormones, the most common being testosterone. They are produced mainly by the ovaries and adrenal glands and have roles in reproductive health, bone and muscle health, sexual function and wider physiology. […]