Amniotic fluid scan (AFI)
Quick answer: An AFI scan measures the amount of amniotic fluid around the baby. It can be combined with an estimate of the baby's weight (EFW). Doctors order it in later pregnancy to check for too little or too much fluid, or when the baby's growth or movements are a concern.
- SampleImaging (no sample)
- TakesAbout 15 to 20 minutes
- Before the testNo special preparation is usually needed.
- In fertility careFluid levels help doctors judge how well the baby is doing in later pregnancy.
How the test is done
- 1You lie on your back or tilted slightly to one side
- 2Gel is spread across your belly
- 3The sonographer divides the womb into four parts and measures the deepest fluid pocket in each
- 4The measurements are added to give the AFI, and the baby's weight may be estimated
What your results can mean
Reading your report
Measurements are compared with what is expected for the stage of pregnancy; your doctor will explain what your report means for you and your baby.
If the result is outside the usual range
A low fluid level (oligohydramnios) can be seen with waters leaking, a placenta not working well, or a pregnancy past its due date. A high level (polyhydramnios) can be seen with diabetes, twins or some conditions in the baby, and is often mild with no cause found.
Who usually has this test
Pregnant women in later pregnancy with a baby measuring small or large, leaking fluid, reduced movements, diabetes, or going past the due date.
Risks and aftercare
It uses sound waves with no radiation and is considered safe for the baby; tell staff if lying on your back makes you dizzy.
Names and options
Also called: AFI scan, amniotic fluid index, AFI and EFW, liquor scan
Options
- Fluid check only (AFI)
- Fluid check with estimated baby weight (AFI and EFW)
Listed by the hospital as
- ULTRASOUND SCAN AFI ONLY
- ULTRASOUND SCAN AFI & EFW
Questions about this test
What does AFI mean?
AFI stands for amniotic fluid index, a way of measuring the fluid around the baby by adding pockets from four parts of the womb. Some units measure the single deepest pocket instead.
Can drinking more water raise my amniotic fluid?
Drinking well may help a little in some women with mildly low fluid, but it does not treat the cause. Follow your doctor's advice on fluids and monitoring.
What should I do if I think my waters are leaking?
Contact your doctor or hospital straight away. Leaking fluid can lower the fluid level and raise the risk of infection, so it needs to be checked.
Related tests
Tamara Hospital & IVF Centre, Rajajinagar
34/3, 10th Cross Road, opp. Vardhaka Sardar Patel School, 1st N Block, 2nd Stage, Rajajinagar, Bengaluru 560010
The hospital is open 24 hours. Call before you come to check the timing for your scan or sample collection.
Get directions ↗IVF Pulse fertility care at Tamara Hospital →
Reception
Waiting area
IVF lab
This page explains each test in general terms so you know what to expect. It is not medical advice: your doctor decides which tests you need and what your results mean. Reference ranges differ between laboratories. Updated 4 November 2026.