Amniotic Fluid Volume Assessment

Who Gets the Test?

Amniotic fluid volume is evaluated every time an ultrasound is performed on your baby. It's a standard way of checking on your baby's health. Your doctor will also do this test during a biophysical profile.

What the Test Does

Amniotic fluid surrounds your baby in your womb. It cushions your baby, and helps your baby's lungs, digestive system, and muscles develop. While you're pregnant, your doctor will keep track of your amniotic fluid levels. If they're too low or too high, you're more likely to have complications, such as early delivery. It may also mean there's a problem with your baby or the placenta.

During a normal ultrasound, your doctor or an ultrasound technician will check on your amniotic fluid levels. There are a few ways to estimate amniotic fluid volume. They include amniotic fluid index (AFI) and deep pocket measurements.

How the Test Is Done

Your doctor or a lab technician will estimate your amniotic fluid volume by measuring fluid pockets during an ultrasound. There's no risk to you or your baby.

What to Know About Test Results

Low levels of amniotic fluid are riskier early in your pregnancy. They can be a sign that your baby is growing too slowly. If it occurs late in pregnancy, it can be a sign of placental failure. Your doctor may want to monitor your pregnancy more closely.

High levels of amniotic fluid often don't cause any problem. But high levels do increase your risk of early delivery or growth problems. You may need more frequent ultrasounds. Medication or a procedure to drain excess fluid can help in some cases.

How Often the Test Is Done During Your Pregnancy

Your doctor or technician will check your amniotic fluid whenever you get an ultrasound. If you have problems during pregnancy, you may need tests more often.

Other Names for This Test

Amniotic Fluid Index (AFI), deep pocket measurements

Tests Similar to This One

Biophysical profile

WebMD Medical Reference Reviewed by Traci C. Johnson, MD on June 25, 2018

Sources

SOURCES

UptoDate: Assessment of Amniotic Fluid Volume

Pagana KD, Pagana TJ. Mosby’s Diagnostic and Laboratory Test Reference, 10th ed. Mosby: 2010. p447.

Johns Hopkins Manual of Gynecology and Obstetrics, 4th Edition. Lippincott Williams & Williams, 2010. pp110-111.

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