Estriol (E3)
How to prepare
You can eat and drink normally before the test.
No special preparation needed.
Tell our phlebotomist about any medicines you take. Don't stop them without asking your doctor.
Wear a loose sleeve so the sample can be taken easily from your arm.
How it works
About this test
Estriol (E3) is a hormone made by the placenta and the baby's liver during pregnancy. Unconjugated estriol is used in prenatal screening (triple and quadruple marker tests).
Why is this test done?
- Part of second-trimester screening for Down syndrome and other conditions
- Assess placenta and baby wellbeing
Symptoms — when should you get tested?
- Routine pregnancy screening at 15–20 weeks
Normal range
Reference ranges differ slightly between labs, methods, age and sex. Always discuss your report with your doctor.
If your result is high
Higher estriol is usually not a concern.
If your result is low
A low estriol value (below about 0.5 MoM) can increase the calculated risk for some chromosomal conditions. It is a screening result, not a diagnosis.
Common reasons- Down syndrome or Edwards syndrome risk
- Placental problems
- Wrong pregnancy dating
How is the test done?
- 1Book online
Choose your slot for home collection or a visit to our centre.
- 2Blood sample taken
A trained phlebotomist takes a small blood sample from a vein in your arm with a sealed, single-use needle. It takes about 2 minutes.
- 3Tested in our lab
Your barcoded sample is tested on automated machines with strict quality checks.
- 4Report on WhatsApp
A pathologist checks the result and the report reaches you on WhatsApp and email.
Frequently asked questions
Multiple of the median — your value compared with the average for your week of pregnancy.
No fasting is needed for this test. You can eat and drink normally.
Your report is usually ready in same day after the sample reaches our lab. We send it on WhatsApp and email, and you can also download it from the Reports page.
Please call our team to confirm whether home sample collection is available for your location and test.
This test needs a blood sample. No special preparation needed.