A plain-English guide to what these hormones do, how they change through life and when testing may help
Oestrogen, progesterone and testosterone: the quick guide
Hormones are chemical messengers. They travel through the bloodstream and help coordinate processes across the body. Oestrogen, progesterone and testosterone are often called sex hormones because of their roles in puberty, menstruation, fertility, pregnancy and sexual function, but their effects reach bone, muscle, the brain, skin and other tissues too.
All three are present in women. The main difference is their typical concentration, where they are produced and how their levels change. They do not work as three separate switches: they operate within a wider network involving the brain, pituitary gland, ovaries, adrenal glands, thyroid hormones, insulin and cortisol.
| Hormone | Main roles | Typical pattern |
|---|---|---|
| Oestrogen | Reproductive development, cycle signalling, womb lining, bone and vaginal tissues | Rises in puberty; fluctuates each cycle; becomes more erratic in perimenopause and settles at a lower level after menopause |
| Progesterone | Prepares and stabilises the womb lining after ovulation; supports pregnancy | Rises mainly after ovulation; may become lower or less predictable when ovulation is irregular; remains low after menopause |
| Testosterone | Contributes to sexual function, muscle and bone; also acts as a source for oestrogen | Present throughout life; generally declines gradually with age rather than dropping suddenly at natural menopause |
What is oestrogen and what does it do?
Oestrogen is not a single hormone but a family of hormones. Oestradiol is the most active form during the reproductive years; oestrone becomes relatively more prominent after menopause; and oestriol is produced in much larger amounts during pregnancy. The ovaries are the main source of oestradiol before menopause. Other tissues, including body fat, can also make oestrogens from hormone precursors, some of which come from the adrenal glands.
Oestrogen helps to:
- drive breast and reproductive development during puberty
- coordinate the menstrual cycle and help thicken the womb lining before ovulation
- maintain vaginal and urinary tissues;
- support bone strength by limiting bone breakdown
- influence the brain, blood vessels, skin and other tissues
During a menstrual cycle, oestradiol is relatively low at the start, then rises as a follicle develops. A sustained rise helps trigger the hormonal events that lead to ovulation. If pregnancy does not occur, oestrogen and progesterone fall before the next period begins.
What is progesterone and what does it do?
Progesterone is produced mainly by the corpus luteum, the temporary structure left behind in the ovary after an egg is released. This means progesterone is closely linked to ovulation: it is usually low during the first half of the cycle and rises after ovulation during the luteal phase.
Its central role is to prepare the womb lining for a possible pregnancy and help keep that lining stable. If pregnancy does not occur, the corpus luteum breaks down, progesterone falls and menstruation follows. During pregnancy, progesterone remains high and is later produced mainly by the placenta.
Progesterone should not be confused with every progestogen. Progestogen is the umbrella term for substances that act at progesterone receptors; progesterone is the naturally occurring hormone, while progestins are synthetic medicines with progesterone-like effects. These distinctions matter in contraception and menopausal hormone therapy.
What is testosterone and why do women need it?
Testosterone is often labelled a 'male hormone', but women produce it too. Before natural menopause, testosterone and related androgens come from the ovaries and adrenal glands. Some testosterone can also be converted into oestrogen in body tissues.
In women, testosterone contributes to sexual function and has roles in muscle, bone and general tissue health. However, libido is influenced by far more than a single blood result: relationship factors, sleep, stress, pain, medicines, mood, vaginal symptoms and wider health can all matter.
Testosterone typically declines gradually from early adulthood. It does not show the same abrupt fall at natural menopause as oestrogen. Surgical removal of both ovaries can produce a more sudden change. Testosterone treatment is a medical decision; in UK menopause care it may be considered for persistent low sexual desire after assessment when menopausal hormone therapy alone has not been effective.
Hormone timeline: how levels change through a woman’s life
The timeline below shows broad patterns, not target numbers. Every person’s not target numbers. Every person’s experience is different, and menstrual cycles themselves create large day-to-day changes.
| Life stage | Typical hormone pattern | What is happening |
|---|---|---|
| Puberty | Oestrogen and androgens rise; ovulation may be irregular at first | Breasts and reproductive tissues mature, body composition changes and periods begin |
| Reproductive years | Oestrogen and progesterone rise and fall across ovulatory cycles; testosterone is present at lower concentrations | The brain, pituitary gland and ovaries coordinate the cycle; patterns vary with pregnancy, breastfeeding and contraception |
| Early perimenopause | Oestrogen can swing high and low; ovulation becomes less consistent, so progesterone may be less predictable | Cycle length and flow may change; symptoms can occur even when a single test looks ‘normal’ |
| Late perimenopause | Longer gaps without ovulation; oestrogen remains variable but trends down; progesterone is often low | Periods become more widely spaced before the final menstrual period |
| Menopause and beyond | Oestrogen and progesterone settle at lower levels; testosterone generally continues its gradual age-related decline | Menopause is reached after 12 months without a period; some lower-oestrogen effects can continue after hot flushes improve |
For a closer look at the transition itself, read What is perimenopause and how can you manage symptoms?
How oestrogen and progesterone work together
Oestrogen and progesterone are often discussed as opposites, but 'balance' is not a fixed 50:50 ratio. Their relationship changes by life stage and, during the reproductive years, by the day of the cycle.
Before ovulation, rising oestrogen helps build the womb lining. After ovulation, progesterone changes that lining so it is ready for a possible pregnancy and limits further oestrogen-driven growth. If pregnancy does not occur, both hormones fall and a period begins.
This is also why progesterone or another progestogen is normally needed alongside systemic oestrogen in menopausal hormone therapy when a woman still has a womb: it protects the womb lining. That is a medical use of measured hormones, not something a food supplement can replicate.
How testosterone interacts with oestrogen and progesterone
Testosterone belongs to a group of hormones called androgens. Through an enzyme called aromatase, some testosterone and other androgens can be converted into oestrogens. This pathway operates in several tissues and remains relevant after menopause, when ovarian oestradiol production has fallen.
All three hormones also feed information back to the brain and pituitary gland. Those signals influence follicle-stimulating hormone (FSH) and luteinising hormone (LH), which help coordinate follicle development, ovulation and ovarian hormone production. The system is a feedback network, not a simple chain with one hormone controlling everything else.
What is the link between cortisol and female sex hormones?
Cortisol is made by the adrenal glands and helps the body respond to stress, regulate energy availability and maintain a normal daily rhythm. It is essential, not inherently harmful. Stress can affect sleep, appetite, mood and menstrual patterns, while changing sex hormones may influence how stress is experienced.
The reproductive system and the hypothalamic-pituitary-adrenal stress system communicate in complex ways, but popular claims that the body 'steals progesterone' to make cortisol or that adrenal glands take over ovarian hormone production are oversimplifications. Persistent stress symptoms deserve practical support and, when needed, medical assessment rather than an assumption that cortisol has directly caused a sex-hormone deficiency.
Explore the subject in more detail in Cortisol, stress and menopause explained.
How do I know if my hormones are out of balance?
'Hormone imbalance' is a broad phrase, not a diagnosis. Symptoms such as irregular periods, hot flushes, low mood, acne, hair changes, tiredness, poor sleep or changes in sexual desire can be related to hormones, but they can also have other causes. Thyroid disorders, anaemia, pregnancy, polycystic ovary syndrome, medication effects, sleep disorders and mental health conditions can overlap with hormone-related symptoms.
Self-assessment has important limits:
- symptoms are not specific to one hormone
- levels change across the day and menstrual cycle
- perimenopausal hormone levels can fluctuate markedly from one test to the next
- a result needs to be interpreted alongside age, cycle timing, symptoms, medicines and medical history.
If symptoms are new, persistent, severe or affecting daily life, speak to your GP. Seek prompt medical advice for very heavy bleeding, bleeding after sex, bleeding after menopause, severe pelvic pain, fainting, suspected pregnancy or symptoms that concern you.
When are hormone blood tests useful?
Testing depends on the question being asked. A GP may arrange targeted tests when periods stop unexpectedly, symptoms occur at a younger age, fertility is a concern, androgen excess is suspected or another condition needs to be ruled out.
For otherwise healthy people aged 45 or over with typical perimenopause or menopause symptoms, UK guidance generally supports diagnosis from symptoms and menstrual history rather than routine hormone testing. A single FSH, oestradiol, progesterone or testosterone result cannot provide a complete 'hormone balance' score. Tests may be appropriate between 40 and 45 or under 40 when early menopause or premature ovarian insufficiency is suspected, but interpretation should be clinical.
Home tests can supply numbers, but they cannot replace medical interpretation. If you do use one, avoid changing medication or taking hormone-active products based on the result alone.
How to support hormonal wellbeing through lifestyle
Lifestyle cannot freeze hormones at a particular level, but it can support the systems affected by hormonal change.
Useful foundations include:
- regular resistance and weight-bearing exercise for muscle and bone
- adequate protein, fibre and a varied, plant-rich diet
- calcium and vitamin D intake appropriate to your individual needs
- consistent sleep routines and daylight exposure
- stress-management practices that are realistic enough to repeat
- limiting smoking and keeping alcohol within recommended limits
- seeking evidence-based treatment when symptoms need more than self-care
Plant foods such as soya, flaxseed and legumes contain compounds called phytoestrogens. They are not the same as human oestrogen.
Read Phytoestrogens: what they are and food sources for a balanced guide.
Where supplements may fit
Food supplements should be positioned as support for general wellbeing, nutrient intake or specific permitted functions - not as a way to diagnose, replace or directly 'rebalance' oestrogen, progesterone or testosterone. No supplement should be used instead of prescribed treatment or assessment for persistent symptoms.
Female Hormone Support is a multi-ingredient formula designed to sit alongside a healthy lifestyle during perimenopause and menopause. Cellular Calm Complex focuses on nutritional and botanical support for calm and stress resilience. Neither product should be described as directly raising or lowering sex-hormone levels.
Check the full ingredient list and speak to a pharmacist or GP before starting a supplement if you take medication, have a health condition, are pregnant or breastfeeding, or are receiving treatment for a hormone-sensitive condition. For more evidence-led guidance, explore the Hormone Hub.
Frequently asked questions
What is the difference between oestrogen and progesterone?
Oestrogen helps coordinate reproductive development and builds the womb lining before ovulation. Progesterone rises mainly after ovulation and changes and stabilises that lining for a possible pregnancy. Their relationship changes across the cycle and through life; there is no universal ideal ratio.
Which hormone falls first in perimenopause?
There is no identical sequence for everyone. Ovulation often becomes less consistent, making progesterone less predictable, while oestrogen can fluctuate sharply before trending lower. This variability is one reason a single blood test may not explain symptoms.
Can stress lower progesterone or oestrogen?
Severe or prolonged physical or psychological stress can disrupt the brain signals involved in ovulation and menstrual cycles in some people. However, the relationship is complex, and symptoms should not automatically be explained as 'cortisol stealing progesterone'. A GP can assess persistent cycle changes.
Can supplements balance oestrogen and progesterone?
Food supplements cannot reliably diagnose or directly balance sex hormones, and they should not be presented as substitutes for HRT or other treatment. Some may support nutrient intake, sleep or general wellbeing, but claims should be specific, evidence-based and legally permitted.
Should I ask for a hormone test during perimenopause?
If you are 45 or over with typical symptoms, diagnosis is often based on symptoms and menstrual history rather than routine hormone blood tests. Testing can be helpful in selected circumstances, especially at younger ages or when another condition is suspected. Discuss your symptoms with your GP.
The key takeaway
Oestrogen, progesterone and testosterone work as part of a changing hormonal network. Their typical patterns shift across the menstrual cycle and through puberty, pregnancy, perimenopause, menopause and later life. Understanding those patterns can make symptoms feel less mysterious, but it cannot replace a diagnosis. When something feels wrong, the most useful next step is not to guess which hormone is 'out of balance' - it is to seek an assessment that considers the whole picture.
Editorial sources and helpful links.
Endocrine Society: Reproductive hormones
NCBI Bookshelf: Physiology, female reproduction
NHS: Menopause and perimenopause
NICE guideline NG23: Menopause identification and management
Medical disclaimer: This article is for general information only and does not replace personalised medical advice, diagnosis or treatment. Speak to a qualified healthcare professional if you have symptoms, a health condition or questions about testing, medicines or supplements.
