What is a non-stress test?

• A non-stress test (or NST) is a simple and painless way to check on the well being of your baby.

What happens during the test?

• This test is usually done in the doctor's office.
• You will be lying down for the test.
• You will have 2 belts strapped around your abdomen. One is used to measure the baby's heartbeat and the other one checks for contractions. These two belts will be attached to a fetal monitor.
• The test usually takes 20-30 minutes, but can take longer depending on how active your baby is or if you are carrying more than one baby.

What should the test results show?

• An NST is "reactive" if the baby's heartbeat is in the range of 120-160 beats per minute. The baby's heartbeat should increase in response to movement. If you are less than 36 weeks pregnant, there should be no contractions.
• If your NST is "not reactive" don't panic. Usually there is nothing wrong with the baby. An ultrasound can be done to be sure your baby is doing okay.

Why do I need an NST?

• NST's are done to check and see if your baby is doing well and is strong enough for delivery. Some of the most common reasons for an NST are:
• Decreased movement of the baby or no movement of the baby
• Gestational diabetes or diabetes before pregnancy
• More than one baby (twins, triplets)
• High blood pressure
• Pre-eclampsia
• Preterm labor or a history of preterm delivery
• Being over-due (pregnancy that is lasting longer than 40 weeks)
• Mom over the age of 35 years
• Abnormal laboratory tests (such as an abnormal AFP)
• Thyroid problems

If you have any questions about your NST or why an NST has been ordered, discuss this with your doctor.