Hormone Profile

Luteinising hormone, commonly known as LH, is a chemical messenger produced by the pituitary gland, a small, pea-sized structure at the base of your brain. It plays a central role in reproductive health for both men and women, acting as a key signal in the complex hormonal conversation that governs fertility and sexual function. In women, LH is best known for triggering ovulation, the moment each month when a mature egg is released from the ovary, making conception possible. In men, LH sends a signal to specialised cells in the testes to produce testosterone, the hormone responsible for many aspects of male health. Think of LH as a conductor in an orchestra, it does not play the instruments itself, but without its direction, the other hormones cannot perform their parts in harmony. Your pituitary gland carefully adjusts how much LH it releases based on feedback from your sex hormones, maintaining a delicate balance throughout your cycle or daily rhythm. When LH levels are within a healthy range, it is a reassuring sign that this feedback loop is working as it should. A number of factors can influence your LH levels, including age, stress, significant changes in body weight, and intense physical exercise. In women, LH naturally fluctuates throughout the menstrual cycle, peaking sharply just before ovulation, so the timing of your blood test matters. Certain medications, including hormonal contraceptives, can also affect your results. If your LH level falls outside the expected range, it is well worth having a conversation with your GP, who can look at it alongside your other hormone results and help you understand what it means for you personally.

Follicle stimulating hormone, or FSH, is another vital messenger produced by the pituitary gland, and it works hand in hand with LH to support your reproductive system. As its name suggests, FSH stimulates the growth and maturation of follicles in the ovaries, the tiny fluid-filled sacs that each contain a developing egg. In men, FSH plays an equally important role by supporting the production of sperm within the testes. Healthy FSH levels are a positive indicator that your body's reproductive signalling is functioning well, which matters not just for fertility but for your broader hormonal balance too. You can think of FSH as the gardener that nurtures seeds before they are ready to bloom; without adequate FSH, eggs cannot mature properly in women, and sperm production may be less efficient in men. The pituitary gland fine-tunes FSH release based on signals it receives from the ovaries or testes, when sex hormone levels are sufficient, FSH production eases off, and when they dip, it ramps up. This elegant feedback system keeps your reproductive hormones in equilibrium. Your FSH levels can be influenced by several factors. Age is one of the most significant, in women approaching the menopause, FSH tends to rise as the ovaries gradually produce less oestrogen, and this is a perfectly normal part of ageing. Stress, being significantly underweight or overweight, and certain medications can also shift your levels. In women of reproductive age, FSH varies across the menstrual cycle, so the day your blood is drawn can affect the reading. If your FSH result is higher or lower than expected, your GP can interpret it in the context of your age, symptoms, and other hormone levels to give you a clear picture of your health.

Testosterone is often thought of as the primary male sex hormone, but it is genuinely important for everyone. Produced mainly in the testes in men and in smaller amounts by the ovaries and adrenal glands in women, testosterone influences a remarkably wide range of bodily functions, from muscle strength and bone density to mood, energy levels, and libido. Maintaining healthy testosterone levels supports your overall vitality and sense of wellbeing, regardless of your sex. Imagine testosterone as the fuel that keeps several of your body's engines running smoothly, your muscles use it to repair and grow after exercise, your bones rely on it to stay strong and dense, and your brain depends on it for motivation and mental clarity. In men, testosterone also drives the development of male physical characteristics during puberty and continues to support reproductive health throughout life. In women, even though levels are much lower, testosterone contributes to energy, sexual desire, and muscle tone. Your body carefully regulates testosterone through a feedback loop involving the pituitary gland and the hypothalamus, adjusting production to keep levels within an optimal range. Several lifestyle and biological factors can affect your testosterone levels. In men, levels naturally decline gradually from around the age of thirty, typically by about one to two per cent per year. Poor sleep, chronic stress, excess body fat, a sedentary lifestyle, and excessive alcohol intake can all contribute to lower levels. For men, the British Society for Sexual Medicine (BSSM) provides simple guides for interpreting total testosterone. A level above 12 nmol/L is generally considered sufficient. A level between 8 and 12 nmol/L sits in a borderline range, where free testosterone, symptoms, and other markers help guide interpretation. A level below 8 nmol/L suggests Testosterone Deficiency that usually warrants clinical assessment. For men on testosterone therapy, BSSM additionally targets a 15 to 30 nmol/L treatment band, with values above 30 nmol/L sitting above this band and warranting a discussion with your clinician about dose timing or repeat measurement. Morning samples (8-11 am) and a confirmatory repeat are typically used before treatment is considered. For women, reference ranges are much lower and are interpreted differently depending on age and life stage. These thresholds are guides, not diagnoses, and your GP will weigh them alongside your symptoms, SHBG, free testosterone, and overall clinical picture. In women, testosterone may fluctuate with the menstrual cycle and tends to decrease after the menopause. Certain medications, including hormonal contraceptives and corticosteroids, can also have an effect. If your testosterone result is outside the expected range, your GP can assess it alongside other markers such as SHBG and free testosterone to build a complete picture and discuss any next steps with you.

Free testosterone measures the small but mighty fraction of testosterone that circulates in your bloodstream without being attached to any carrier proteins. While total testosterone tells you how much of the hormone is present overall, only about one to three per cent of it is truly free, unbound and ready to enter your cells and do its work. This makes free testosterone an especially useful marker, as it reflects the amount of the hormone that is actively available to your muscles, bones, brain, and other tissues. Think of it this way: if total testosterone is the money in your bank account, free testosterone is the cash in your wallet, it is the portion you can actually spend right now. The rest of your testosterone travels bound to proteins, primarily sex hormone binding globulin and albumin, which act like a storage system, releasing testosterone gradually as your body needs it. When SHBG levels are high, more testosterone is locked away and less is free; when SHBG is low, more testosterone is available in its active form. This is why free testosterone can sometimes tell a different story from your total testosterone reading, and why clinicians often find it valuable to look at both together. Several factors influence your free testosterone levels. Because SHBG plays such a central role, anything that affects SHBG will indirectly affect free testosterone, for instance, ageing, body weight, liver health, and thyroid function can all shift the balance. In men, free testosterone tends to decline with age, sometimes more noticeably than total testosterone. In women, changes in how the adrenal glands or ovaries function can influence levels. Lifestyle factors such as exercise, diet, sleep quality, and stress also play a part. If your free testosterone result raises any questions, your GP can interpret it alongside your total testosterone and SHBG to give you a thorough understanding of your hormonal health. For men, the British Society for Sexual Medicine (BSSM) provides a clear guide for interpreting calculated free testosterone. A level above 0.225 nmol/L (roughly 65 picograms per millilitre) is generally considered sufficient. A level below 0.225 nmol/L suggests testosterone deficiency and is most informative when total testosterone sits in the borderline range of 8 to 12 nmol/L, where free testosterone helps confirm whether the bioavailable fraction is genuinely low. A level above 0.70 nmol/L sits above the typical adult-male range and is worth discussing with your clinician, particularly to consider sample timing or repeat measurement. Morning samples (8-11 am) and a confirmatory repeat are typically used before clinical conclusions are drawn. For women, reference ranges are much lower and are interpreted differently depending on age and life stage. These thresholds are guides, not diagnoses, and your GP will weigh them alongside your total testosterone, SHBG, symptoms, and overall clinical picture.

17-beta oestradiol is the most potent and abundant form of oestrogen in your body, and it is the marker most commonly measured when clinicians want to assess oestrogen status. Produced primarily by the ovaries in women and in smaller amounts by the testes and adrenal glands in men, oestradiol plays a fundamental role in reproductive health, bone strength, cardiovascular wellbeing, and even brain function. Maintaining healthy oestradiol levels supports a wide range of systems that contribute to how well you feel day to day. Think of oestradiol as a versatile caretaker that looks after many different areas of your health simultaneously. In women, it drives the development and maintenance of reproductive tissues, regulates the menstrual cycle, and helps keep the lining of the womb healthy. It also encourages your bones to retain calcium and stay dense, supports the elasticity of blood vessels, and influences mood by interacting with neurotransmitters in the brain. In men, oestradiol is present at much lower levels but still matters, it contributes to bone health, brain function, and the regulation of libido. Your body produces oestradiol through a process that begins with cholesterol and involves several enzymatic steps, with the final conversion often occurring in the ovaries, fat tissue, or other peripheral sites. Oestradiol levels are influenced by many factors. In women of reproductive age, levels fluctuate significantly throughout the menstrual cycle, peaking just before ovulation and dropping during menstruation, so the timing of your blood test is important for interpretation. During the menopause transition, oestradiol gradually declines, which is a natural part of ageing. Body fat percentage matters too, fat tissue can produce oestrogen, so higher body weight may be associated with elevated levels. Medications such as hormonal contraceptives, hormone replacement therapy, and aromatase-related treatments can all affect your reading. If your oestradiol result is higher or lower than expected, your GP can put it in context with your symptoms, cycle timing, and other hormone levels to guide any next steps.

Progesterone is a hormone that plays a central role in the menstrual cycle, pregnancy, and overall hormonal balance. Produced mainly by the ovaries after ovulation, specifically by a temporary structure called the corpus luteum, progesterone prepares the lining of the womb to receive a fertilised egg and helps maintain the early stages of pregnancy. Beyond reproduction, progesterone also influences mood, sleep quality, and the way your body manages inflammation, making it an important marker for your general wellbeing. You can think of progesterone as the hormone that gets things ready and keeps things calm. After ovulation, progesterone rises to create a nurturing environment in the womb, and if pregnancy does not occur, it drops away, triggering menstruation and the start of a new cycle. This rise and fall is a perfectly healthy rhythm that your body repeats each month. Progesterone also has a gently calming effect on the brain, it interacts with receptors that promote relaxation and restful sleep, which is why some women notice changes in their sleep patterns or mood at different points in their cycle. In men, progesterone is produced in small amounts by the adrenal glands and testes and serves as a precursor for other hormones, including cortisol and testosterone. Because progesterone levels change dramatically throughout the menstrual cycle, the timing of your blood test is particularly important. Levels are typically at their highest about a week after ovulation, during the luteal phase, and are very low during the first half of the cycle. Stress can affect progesterone production, as can significant changes in body weight, intense exercise, and age, levels naturally decline in the years leading up to and during the menopause. Certain medications, including hormonal contraceptives and progesterone supplements, will also influence your results. If your progesterone level is outside the range your clinician expects, especially in relation to where you are in your cycle, your GP can help interpret it and discuss what it means for your health.

Prolactin is a hormone produced by the pituitary gland, and while it is best known for its role in stimulating milk production after childbirth, it actually has a surprisingly broad range of functions in both men and women. Prolactin is involved in immune regulation, reproductive function, and the balance of other hormones, making it a useful marker for understanding your overall hormonal health. Healthy prolactin levels are a reassuring sign that your pituitary gland, the master controller of many hormonal systems, is working as it should. Imagine the pituitary gland as a control tower at an airport, sending out signals to keep everything running on schedule. Prolactin is one of those signals, and while its most dramatic role is enabling breastfeeding, it also helps regulate the menstrual cycle in women and supports healthy reproductive function in men. Prolactin interacts closely with other hormones, particularly dopamine, which acts as a natural brake on prolactin release. When dopamine levels are adequate, prolactin stays within a healthy range; when dopamine signalling is disrupted, prolactin can rise. Elevated prolactin can sometimes affect menstrual regularity in women or libido and energy in men, so it is a valuable piece of the hormonal puzzle. Several factors can temporarily raise your prolactin levels without there being any underlying concern. Stress is one of the most common, even the mild stress of having a blood test can cause a transient spike. Exercise, sleep, certain foods, and the timing of your blood draw can also influence your reading, which is why a morning fasting sample is often recommended. Some medications, particularly certain antidepressants, anti-nausea drugs, and antipsychotics, are well known for raising prolactin. In women, prolactin naturally rises during pregnancy and breastfeeding. If your prolactin level comes back higher or lower than expected, try not to worry, your GP may suggest a repeat test to confirm the result and can investigate further if needed, looking at it in the context of your symptoms and other hormone levels.

DHEA-sulphate, often written as DHEAS, is a hormone produced primarily by the adrenal glands, the small, triangular glands that sit on top of each kidney. It serves as a precursor hormone, meaning your body uses it as a raw material to manufacture other important hormones, including testosterone and oestrogen. Because of this upstream role, DHEAS provides a helpful window into how well your adrenal glands are functioning and how your body manages its broader hormonal supply chain. You can think of DHEAS as a versatile ingredient in your body's hormone kitchen, on its own it has relatively mild effects, but it can be converted into a variety of more potent hormones depending on what your tissues need at any given time. This conversion happens locally in your cells, which means different parts of your body can tailor the hormone supply to their own requirements. DHEAS circulates in relatively large quantities compared to other hormones, and because its levels remain fairly stable throughout the day, it is a convenient and reliable marker to measure. Healthy DHEAS levels are associated with a general sense of energy and wellbeing, and they support immune function, mood, and resilience to stress. One of the most notable features of DHEAS is that it peaks in your twenties and then gradually declines with age, this is entirely normal and is one of the most predictable hormonal changes your body goes through. By the time you reach your seventies, levels may be only ten to twenty per cent of what they were at their peak. Beyond ageing, DHEAS can be affected by chronic stress, because the adrenal glands are also responsible for producing cortisol, your body's main stress hormone, and prolonged stress can shift the balance of adrenal output. Certain medications, particularly corticosteroids, can also influence your levels. If your DHEAS result is unexpectedly high or low for your age, it is a good idea to discuss it with your GP, who can consider it in the context of your overall health and other hormone results.

Dihydrotestosterone, commonly known as DHT, is the most potent androgen in your body and plays a central role in male development and physiology. It is produced when the enzyme 5-alpha reductase converts testosterone into DHT, a process that occurs primarily in the prostate, skin, hair follicles, and liver. Although DHT is present at much lower circulating levels than testosterone, it binds to androgen receptors with roughly three to five times greater affinity, making it the dominant driver of androgen-dependent functions in specific tissues. DHT is essential for the development of male sex characteristics during puberty and continues to support sexual function, prostate health, and neurological wellbeing throughout life. Think of DHT as the amplified version of testosterone, fine-tuned for specific jobs. While testosterone is the general-purpose androgen circulating throughout your body, DHT is the specialist that your tissues produce locally when they need a stronger signal. In the prostate, DHT drives glandular growth and function. In the brain, it serves as a precursor to neurosteroids like allopregnanolone, which modulate GABA receptors and are directly involved in mood regulation, stress resilience, and cognitive clarity. In the skin and hair follicles, DHT influences sebum production and, in genetically susceptible individuals, can contribute to androgenetic alopecia by triggering follicular miniaturisation. Crucially, DHT does not cause hair loss on its own; genetics determine follicle receptor sensitivity, which is why two men with identical DHT levels can have completely different hairlines. DHT levels are influenced by several factors. Testosterone availability is the primary determinant, since DHT is derived from it, so anything that affects testosterone will indirectly affect DHT. The activity of 5-alpha reductase varies between individuals due to genetics, and it can be modified by medications such as finasteride and dutasteride, which block the enzyme and reduce DHT production by approximately 70 per cent. Body composition, insulin resistance, and liver function can all influence conversion rates. Age plays a role too, as 5-alpha reductase activity tends to increase in prostate tissue with age, contributing to benign prostatic hyperplasia. If your DHT result is outside the expected range, your GP can interpret it alongside testosterone, SHBG, and free testosterone to assess your overall androgen metabolism and discuss any implications.