Tag: PCOS diagnosis UK

Research shows that on average, it takes two years and visits to three different doctors for someone to get a diagnosis of polycystic ovary syndrome (PCOS), even though it’s one of the most common hormonal conditions in the UK, affecting around 1 in 10 women. Part of the problem is that PCOS presents differently in different people. There’s no single symptom that confirms it, no single test that catches every case, and whilst the  diagnostic criteria is  clinically sound, it requires ruling out other conditions before it can be applied. Add  that to the reality that many GPs have limited time and variable knowledge of reproductive hormones,  it’s not difficult to understand why so many people spend years being told their symptoms are normal, or being tested for the wrong things. This guide walks through exactly how PCOS is diagnosed: the criteria clinicians use, the tests involved, what the process typically looks like, and what you can do if you’re struggling to get answers. Quick Facts How is PCOS diagnosed? PCOS is most commonly diagnosed using what’s known as the Rotterdam criteria, established by an international consensus in 2003 and last updated in 2023. To receive a PCOS diagnosis, a person must meet at least two of the following three criteria: 1. Irregular or absent menstrual cycles. This means cycles that are consistently shorter than 21 days, longer than 35 days, or absent altogether. Irregular cycles indicate that ovulation is not occurring regularly, a key feature of PCOS. According to the 2023 International Evidence-Based PCOS Guidelines, irregular cycles are defined as fewer than eight cycles per year, or cycle intervals outside the 21–35 day range, in women who are at least three years post-menarche (which is your first period). 2. Clinical or biochemical signs of high androgens (hyperandrogenism). This means either physical symptoms associated with elevated androgens such as excess facial or body hair (hirsutism), acne, or scalp hair thinning or elevated androgen levels on a blood test – typically testosterone. Importantly, you don’t need both signs of hyperangrogenism – physical signs alone, or blood results alone, can satisfy this criterion. 3. Polycystic ovarian morphology (PCOM). This refers to the appearance of the ovaries on an ultrasound scan, specifically a high number of small antral follicles (the immature follicles that house eggs) in one or both ovaries, or an increased ovarian volume. Alternatively, a high AMH (anti-Müllerian hormone) level on a blood test can be used as a marker of PCOM when an ultrasound isn’t available or appropriate. Two out of three. That’s the threshold. Which means you can have PCOS without polycystic-looking ovaries on a scan. You can have PCOS without acne or excess hair growth. You can have PCOS with a relatively regular period. This variability is one reason why the diagnosis of PCOS is frequently missed or delayed – there’s no single presentation that fits everyone. What tests might I need to do to get a PCOS diagnosis? A PCOS diagnosis is built from a combination of clinical assessments, blood tests, and often an ultrasound. Here’s what each one involves. Blood tests for PCOS diagnosis Blood tests are central to PCOS diagnosis, both for assessing hormone levels and for ruling out other conditions that can mimic PCOS. The following are typically included in a diagnostic workup: LH and FSH Luteinising hormone (LH) and follicle-stimulating hormone (FSH) are both made by the pituitary gland and work together to regulate the menstrual cycle. In PCOS, LH is often elevated relative to FSH, producing a raised LH:FSH ratio (typically greater than 2:1). This is one of the hormonal patterns clinicians look for in the early follicular phase, ideally tested around day 2–5 of the cycle. Oestradiol Oestradiol (the primary form of oestrogen) is tested alongside FSH to interpret the hormonal picture correctly. High oestradiol can suppress FSH artificially, which is why these two should always be read together. Testosterone and other androgens Testosterone and DHEAS (dehydroepiandrosterone sulphate) are tested to assess androgen levels. Elevated androgens support the hyperandrogenism criterion and help explain symptoms like excess body or facial hair and acne.  SHBG blood test measures the level of a protein called sex hormone binding globulin (SHBG) in your blood. SHBG attaches to sex hormones such as testosterone and estrogen and helps control how much of these hormones are active  in the tissues of your body and to understand how testosterone and oestrogen are working in the body. AMH (anti-Müllerian hormone) AMH is made by the antral follicles in the ovaries (early stage follicles that haven’t been selected for ovulation yet) and reflects the size of your egg reserve. In PCOS, AMH is often significantly elevated becausethere is a high number of small follicles stuck at different stages of development. A high AMH can serve as a marker of polycystic ovarian morphology in clinical settings, particularly when an ultrasound is unavailable. AMH doesn’t fluctuate dramatically across the cycle but is ideally tested on day 3 of the cycle for consistency. Thyroid function tests (TSH and free T4) Both an underactive and overactive thyroid can cause irregular cycles, weight changes, and fatigue that closely resemble PCOS symptoms. Ruling out thyroid issues is a standard part of the diagnostic process. Prolactin Elevated prolactin (hyperprolactinaemia) can also disrupt the menstrual cycle and cause irregular or absent periods. Testing prolactin helps exclude this as an alternative explanation for cycle irregularity. Glucose and insulin / HbA1c Because insulin resistance affects a lot of people with PCOS and significantly impacts its management, assessing metabolic markers such as fasting glucose or HbA1c is an important part of a thorough diagnostic workup. These tests are ideally taken in the early follicular phase, between days 2–5 of the menstrual cycle, when cycling hormones like LH, FSH, and oestradiol are at their baseline. If your cycles are very irregular, your doctor may advise testing at a specific point or to simply proceed whenever possible. Hertility’s Advanced At-home Hormone & Fertility Test checks for these markers including LH, FSH, oestradiol, testosterone, […]