Estradiol (E2) is a key estrogen that guides menstrual cycles, fertility, bones, and overall wellbeing.
Estradiol, or E2, is the main and most active form of oestrogen. In women it is made mostly by the ovaries and changes across the menstrual cycle. Men make smaller amounts, partly by converting testosterone.
Estradiol supports the menstrual cycle and fertility, bone strength, mood, and skin, and it has roles in heart and brain health in both sexes.
Estradiol helps explain cycle and fertility problems, menopause, and some causes of low or high oestrogen in either sex. Because it swings through the cycle, the timing of the test matters.
Low estradiol can signal menopause, ovarian problems, or low pituitary signalling. High levels can relate to ovarian activity, certain tumours, or, in men, excess conversion from testosterone.
Aniva reads your result against research-backed ranges, not just the lab's wide normal. The reference shown below is specific to this biomarker.
Strongly cycle, sex, and menopause dependent. Guidance only and assay dependent. Ranges vary by lab.
| Group or phase | Reference range |
|---|---|
| Women, follicular phase | ~70 to 530 pmol/L |
| Women, mid-cycle peak | ~400 to 1500 pmol/L |
| Women, luteal phase | ~80 to 700 pmol/L |
| Women, postmenopausal | below ~120 pmol/L |
| Men | ~40 to 160 pmol/L |
Source: LOINC 2243-4. Confirm against your own laboratory's range.
Your result, read with the day of your cycle or menopausal status, shows where your oestrogen sits. It supports work on cycle changes, fertility, menopause symptoms, and bone health.
Levels vary widely by cycle day, so timing is essential. Hormonal contraception and hormone therapy change results. High-dose biotin supplements can interfere with certain assays. Low-level assays may be needed for men and postmenopausal women.
Best read together with FSH, LH, and progesterone, and with AMH when ovarian reserve is in question.
What does an estradiol result mean? It reflects your current estrogen level. Context matters—age, cycle day, symptoms, and other hormones help interpret it.
Do I need to fast for this test? No. You can eat and drink normally unless your clinician advises otherwise.
When is the best time to test? For baseline, many test on days 2 to 5 of the cycle. To see the surge, test near mid-cycle. If on hormone therapy, follow your dosing schedule consistently.
Which medicines or supplements affect results? Birth control, estrogen therapy, fertility meds, aromatase inhibitors, SERMs, and testosterone can shift levels. High-dose biotin may skew some assays.
How often should I check estradiol? It depends on your goals. For fertility or therapy monitoring, your clinician may advise targeted checks or repeat tests across a cycle.
How long do results take, and what should I discuss? Results are usually ready in about 7 days. Share your cycle day, symptoms, and medicines to plan any follow-up testing.
One annual membership, 100+ biomarkers, every result explained in plain language with a personalized action plan and concierge guidance.
