Non-Stress Test (NST)

A non-stress test or NST is a very common and painless test done in your health care provider_s office to verify that your baby is doing well.It is done once or twice a week starting at the soonest 28 weeks if you are having a high risk pregnancy. It is also done frequently if the baby is not moving much.It involves tracing, on a piece of graph paper, the changes of the baby_s heart rate over a 20 to 30 minute period. When the baby moves, the heart rate will usually go up and this is called an acceleration. If there two or more accelerations high and long enough, the test is satisfactory and called _reactive_. If you have a reactive NST, the baby is doing well and there is only a small chance for something bad to happen to the baby over the following week. If these accelerations are not seen, the NST is called "non-reactive" and your health care provider will do further testing to ensure that your baby is doing well. Often an ultrasound to look at the amniotic fluid level will be done the same day as the NST in order further ensure the baby_s well being.