Non-Stress Test (NST) Pregnancy - Purpose, Benefits and Risks

Non-Stress Test (NST) Pregnancy - Purpose, Procedure, Benefits, Risks, Cost, and Results

An NST (Non-Stress Test) is a non-invasive prenatal test that measures fetal heart rate, contractions, and response to the movements to ensure your baby's well-being inside your womb. During NST, the baby's heart rate is monitored to see how it responds to the baby's movements. It is also done to ensure that the baby is getting enough oxygen inside the womb. This test is also known as Cardiotocography (CTG). A fetal monitor is used to perform NST.

When NST is done?

NST is done in the third trimester usually after 28 weeks of pregnancy to ensure that the baby is getting enough oxygen for his/her well-being inside the womb. 

What happens during an NST?

During NST, you'll lie on a reclining chair, and a fetal monitor is used which has two sensors that are placed on your belly with two belts that are placed around your waist. One sensor will record the synchrony between your baby's heartbeat and movements and the other one measures uterine contractions. You'll be asked to keep track of the baby's movements. To monitor fetal's heart rate a Cardiotocograph is used. During NST, your doctor will also check your blood pressure at regular intervals. 

What is done when the baby is sleeping during NST?

If your baby seems to be sleeping during NST then your doctor will try to wake up your baby by making noise over your belly or nudging your belly or by using an acoustic simulator. 

(Also read: 8 common tests during the third trimester of pregnancy)

How long does a non-stress test (NST) last?

A non-stress test (NST) is used to evaluate the baby's health before birth which usually lasts 20 to 30 minutes. 

Why is NST done?

NST (Non-Stress Test) is done to assure that the baby is healthy and getting enough oxygen.  

Who should have to do an NST test?

NST test is generally performed if :

• When a mom-to-be has complications such as preeclampsia, heart disease, high blood pressure, or gestational diabetes.

• Previous history of miscarriages or stillbirth.

• If the baby measures small then his/her gestational age. 

• If you have multiple pregnancies with complications.

• If the baby is not active inside the womb. 

• If the baby is at an increased risk of death.

• If your baby is moving less than usual. 

• If you are overdue. 

• Fetal Hypoxia (Intrauterine Hypoxia)

• Rh-Sensitization (Rhesus Sensitization)

• Lack of sufficient Amniotic Fluid (Oligohydramnios)

• Excessive Amniotic Fluid in the Amniotic Sac (Polyhydramnios)

• If you have a high-risk pregnancy.

How often an NST is performed?

NST is usually performed once or twice a week and in some cases, this test is performed daily. The frequency of NSTs performed totally depends on your health and your baby's health. 

(Also read: Blood test for pregnancy)

NST Results 

A normal NST result indicates that the baby is doing well and getting enough oxygen inside the womb. The results of NST are classified into two categories :

Reactive  

If the baby is active, moves a lot, and has a normal heart rate then the result is considered Reactive. If the result of NST is reactive it means your baby is healthy and not under any stress. 

Non-Reactive 

A baby who doesn't make a minimum number of movements or whose heart doesn't accelerate as much as expected when he/she does move during NST then the result is to be considered Non-reactive. However, a non-reactive result doesn't necessarily indicate that your baby is in danger. A non-reactive result may indicate that your baby is not getting enough oxygen inside the womb. 

Is NST safe?

NST is a non-invasive test that is totally safe for you and your baby. It usually records what your baby is doing naturally so it doesn't bother your baby. 

Is NST painful?

No, NST is not painful. It is a painless test for you and your baby. 

(Also read: Pregnancy trimesters and their symptoms)

NST Risks

NST is a non-invasive test which means that this test doesn't involve any physical pain or stress to you and your baby. This test is a risk-free test to ensure your baby's well-being. 

NST benefits

• A nonstress test is painless and safe.

• A non-stress test is an invasive test that doesn't pose any physical risks or stress on the mom-to-be and her baby.

• It is a prenatal test that tells about the health of the unborn baby. 

NST cost

The cost of a fetal NST ranges from $70 to $350.

What to do if you get a non-reactive result in NST?

If you get a non-reactive result during NST don't get panic. Be calm. Getting a non-reactive result doesn't always mean that your baby is in danger. There may be some other reasons such as it might be possible that the baby is sleeping at that time. After a non-reactive result technicians make noise over your belly to encourage the baby to do some movements or they can offer you a sweet drink or NST may be done again after a few hours. 

If your doctor determines that your baby could be under stress then she'll perform further tests such as BPP (Biophysical Profile) or Contraction Stress Test.

BPP (Biophysical Profile) is done to evaluate the following :

• Baby's Heart Rate

• Baby's  Movement

• Baby's  Breathing

• Baby's muscle tone

• Amniotic Fluid Level

Also, read other health-related articles :

• How to get rid of stretch marks during pregnancy?

• How to look beautiful after delivery?

• Benefits of Breastfeeding for the mother and the baby

• Causes of Vaginal Pain during Pregnancy

• Reasons for Spotting during Pregnancy

• Best time to take a pregnancy test

Disclaimer: This content is intended for general information only and it should not be used as the basis of patient treatment. The given content is not intended to be a substitute for professional medical advice, treatment, or any diagnosis. Always consult a doctor for more information. Our website doesn't claim responsibility for this information.