Nonstress Test (NST) With Twins

Who Gets the Test?

The nonstress test is a routine test for women pregnant with twins. It's a simple, safe way of checking on your babies' health.

What the Test Does

The NST records your babies' movement and heartbeat. It notes changes in heart rhythm when your babies go from resting to moving, or during contractions if you're in labor. Your babies' hearts should beat faster when active -- just like yours. The NST can reassure you that your babies are healthy and getting enough oxygen.

It's called a nonstress test because the test won’t bother your babies. Your doctor won't use drugs to make your babies move. The NST records what your babies are doing naturally.

How the Test Is Done

The NST is safe for you and your babies. You'll lie down with three belts around your belly. Two belts measure each of your babies' heartbeats. The third belt measures contractions. When you feel your babies kick or move, you may press a button so your doctor can see how the babies' heartbeats changed while moving. The test will take about 20 minutes.

If your one or both of your babies seem to be sleeping, a nurse may try to wake them by ringing a bell, moving your belly or using an acoustic stimulator.

What to Know About Test Results

A normal nonstress test shows that your babies are getting enough oxygen and doing well. If the results are unusual, your doctor may suggest further testing.

If your babies don't move during the nonstress test, try not to worry. Many women with abnormal results turn out to have perfectly healthy babies. Sometimes, babies sleep through the whole thing.

How Often the Test Is Done During Your Pregnancy

Some women start getting weekly or even twice weekly nonstress tests at around 28 weeks if they have a high risk pregnancy. (Before 28 weeks, the tests are not accurate.)You may need them earlier if you have any signs of problems. Others women may need one isolated NST if the babies are not moving well, for example. It all depends on your own situation. Ask your doctor.

Other Names for This Test


Tests Similar to This One

Contraction stress test

WebMD Medical Reference Reviewed by Traci C. Johnson, MD on July 02, 2018



Pagana KD, Pagana TJ. Mosby’s Diagnostic and Laboratory Test Reference, 10th ed. Mosby: 2010. p456.

ACOG: Special Tests for Monitoring Fetal Health.

Johns Hopkins Manual of Gynecology and Obstetrics, 4th Edition. Lippincott Williams & Williams, 2010.pp91-92.

James D. Goldberg MD, medical director, San Francisco Perinatal Associates, San Francisco.

© 2018 WebMD, LLC. All rights reserved.

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