Estradiol

Measures one of the main forms of estrogen.

To assess ovarian function and hormonal status.

1. Check in advance whether the time of day, the day of your menstrual cycle or other timing matters.
2. Agree on the menstrual cycle day and any hormone preparations with your doctor in advance. The right timing depends on the purpose of the test.
3. Tell your doctor about hormone preparations and dietary supplements; do not change your treatment on your own.
4. Stay calm before the blood draw and keep to the time agreed with you.

Fasting is often not necessary for this test alone. If other tests have also been ordered, or your doctor has prescribed specific preparation, follow the agreed rules.

The menstrual cycle day is chosen according to the clinical purpose; the early phase of the cycle is often needed, but this is not a universal rule.

• Hormone preparations and supplements
• Blood draw time or cycle phase, when relevant
• Immunoassay interference, including biotin on some platforms

Venous blood — serum or plasma, depending on the method

The blood sample is collected by a qualified staff member. The tube type, required volume, and processing and storage conditions are set by the laboratory's specific method. You do not need to store the sample yourself.

Age, sex, time of day, cycle phase and the method used all matter when interpreting the result. The meaning of a high or low result depends on age, symptoms, the method used and the reference interval.

If you are pregnant or have severe abdominal pain, unusual bleeding or significant hormonal symptoms, see a gynecologist/endocrinologist; with emergency signs, seek care immediately.

Do not stop treatment on your own. Confirm the final test conditions with the laboratory.