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Five-marker panel assessing oestrogen-to-progesterone balance, SHBG, and testosterone to investigate relative oestrogen excess.
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A targeted five-marker panel assessing oestradiol, progesterone, the oestradiol-to-progesterone ratio, SHBG, and testosterone.
Oestrogen dominance is not simply about having ‘too much oestrogen’ — it describes a state where oestrogen activity is high relative to progesterone, creating an imbalance that can drive a characteristic cluster of symptoms: heavy or irregular periods, PMS, breast tenderness, bloating, weight gain around the hips and thighs, mood swings, anxiety, and fatigue.
The Oestrogen Dominance Panel measures oestradiol and progesterone together with the oestradiol-to-progesterone ratio — the most clinically useful single indicator of this imbalance. SHBG is included because low SHBG amplifies oestradiol activity by increasing the free fraction available to tissues. Testosterone is included because it converts to oestradiol via aromatase, particularly in adipose tissue — a pathway relevant for women with higher body weight.
Testing must be timed to the mid-luteal phase (approximately day 21 of a 28-day cycle) when progesterone is at its peak. Venous draw required. GMC-physician reviewed results within 3 to 5 working days.
Understand what each marker measures, why it matters, and what the science says — not just a list of numbers.
Primary oestrogen; drives endometrial proliferation, breast tissue growth, and fluid retention when disproportionately high relative to progesterone.
Post-ovulation balancing hormone that opposes oestradiol's proliferative effects; low progesterone relative to oestradiol defines oestrogen dominance.
Carrier protein binding oestradiol and testosterone; low SHBG increases free oestradiol activity and amplifies symptoms.
Can be aromatised to oestradiol, particularly in adipose tissue; relevant in women with higher body fat or excess adrenal androgen.
Calculated ratio reflecting the relative balance between oestrogen and progesterone activity; the key indicator of oestrogen dominance.
This panel is designed for adults who want a comprehensive, evidence-based picture of their metabolic health — not a GP referral panel.
Women with heavy periods, breast tenderness, or significant PMS symptoms
Those experiencing cyclical bloating, mood swings, or anxiety
Women in perimenopause noticing worsening hormonal symptoms
Those wanting to assess whether progesterone insufficiency is contributing to their symptoms
The oestrogen dominance concept is clinically useful but not universally standardised; the oestradiol-to-progesterone ratio is most meaningful when collected at the correct cycle day (mid-luteal, approximately day 21 in a 28-day cycle). Collection on any other cycle day may produce a misleading picture, particularly if ovulation occurred later than day 14. This panel does not include LH or FSH, which are needed to confirm whether ovulation occurred. It does not measure oestrone or oestriol — other oestrogen forms relevant in post-menopausal or HRT contexts. Results should be interpreted alongside symptoms and menstrual history by a clinician familiar with cycle-phase physiology.
From order to physician-reviewed report in as little as three working days.
Three options designed to fit your schedule, location, and preference — all producing a laboratory-standard sample.
Adults 18+ in mainland UK. Not suitable if you have had a transfusion in the last 3 months.
Order anytime; kit dispatched within 24 hours Mon–Fri.
Allow 24–48 hours for sample transit on top of lab processing time.
Adults 18+ within 20 miles of a serviced city centre.
Mon–Sun, 06:00–20:00. Next-day booking typical.
Sample reaches the lab within 24 hours of collection.
Adults 16+ with photo ID. Paediatric draws by appointment at selected sites.
Mon–Fri, with Saturday hours at most metropolitan locations.
Samples processed same-day at the receiving clinic.
Every test is processed in a UKAS ISO 15189-accredited laboratory, overseen by GMC-registered physicians, and governed by UK GDPR. No overseas processing, no offshore data.
Follow these guidelines to ensure accurate, reproducible results. Most markers are sensitive to recent food, exercise, and sleep.
Can't find your answer? Our clinical support team is available Monday to Friday, 9am–5pm.
Contact supportOestrogen dominance describes a state in which oestrogen activity is disproportionately high relative to progesterone — either because oestradiol is genuinely elevated, or because progesterone is insufficient to counterbalance normal oestrogen levels. It is a relative imbalance rather than simply high absolute oestrogen. Common drivers include anovulatory cycles (where no ovulation occurs and therefore no progesterone is produced), stress (which diverts the progesterone precursor pregnenolone towards cortisol production), excess adipose tissue (which converts androgens to oestradiol via aromatase), and declining progesterone in perimenopause while oestrogen fluctuates.
The oestradiol-to-progesterone (E2:P4) ratio compares the two hormones directly and is the most useful single indicator of relative hormonal balance at the mid-luteal phase. In a normally functioning mid-luteal phase, progesterone should be substantially higher than oestradiol — a ratio generally below 100 (using standard nmol/L units for progesterone and pmol/L for oestradiol) is often cited as balanced, though published thresholds vary. A high ratio indicates that oestradiol is disproportionately dominant relative to progesterone, which correlates with oestrogen dominance symptoms. Your physician report will interpret the ratio against clinical context and cycle day.
Yes, but timing becomes more complex. In an irregular cycle, day 21 may not correspond to the mid-luteal peak — ovulation may have occurred later (or not at all). If you have irregular cycles, the best approach is to use ovulation predictor kits (OPKs) at home and test approximately 7 days after a confirmed positive OPK result. If you are not ovulating (anovulatory cycles), progesterone will be uniformly low throughout the cycle, which itself is an important finding that this panel can reveal. Your physician will account for cycle irregularity in the interpretation.
Yes, significantly. Adipose (fat) tissue contains high levels of aromatase, the enzyme that converts androgens (particularly androstenedione and testosterone) into oestrogens. Women with a higher percentage of body fat therefore produce more oestrogen peripherally, independent of ovarian output. This extra oestrogen is not balanced by additional progesterone production, contributing to relative oestrogen dominance. Weight loss — particularly of visceral and subcutaneous fat — reduces aromatase activity and can meaningfully lower oestradiol levels and improve the E2:P4 balance.
Yes — this is often the more accurate description. In many cases, oestradiol is within the normal range, but progesterone is inadequately low, creating relative oestrogen dominance without absolute oestrogen excess. This pattern is particularly common in women with anovulatory cycles, high stress levels (where cortisol competes for the progesterone precursor), or in perimenopause when ovulation becomes irregular. The oestradiol-to-progesterone ratio captures this regardless of whether oestradiol is high or progesterone is low — making the ratio more informative than either value alone.
Bioidentical progesterone supplementation (available as Utrogestan in the UK on prescription, or as regulated topical creams) is used by some women and practitioners to address luteal phase insufficiency or oestrogen dominance symptoms. Whether this is appropriate depends on your clinical picture, confirmed deficiency, and prescribing physician’s assessment. This panel provides the objective data needed for that conversation. Do not start progesterone supplementation without medical guidance — inappropriate use can affect cycle timing and interfere with fertility. Please share your results with your GP or a menopause or hormone specialist.
