Many special tests are conducted during pregnancy, especially if continuous monitoring of the fetus is unavoidable as in following circumstances:

• The pregnancy, which is tagged ‘high risk’
• The pregnancy, in which the fetus is prone to certain issues that may result in stillbirth or preterm birth
• A pregnancy that crossed 40 weeks of gestation
• The multiple pregnancies with complication
• When the maternal heart disease or some heath condition adversely affect the development of the fetus

Non-stress test is one such special test.

What Is Non-Stress Test?

Non-stress test is a simple, noninvasive procedure, which is done in the course of pregnancy to assess the fetal condition. During the test, the technician monitors the heartbeat of the fetus. The heart rate of the fetus both during resting and moving are taken. The basic theory of this test is, just like the frequency of your heartbeat increases when you are active, the fetal heart rate ought to go up while he’s moving or kicking.

When Is Non-Stress Test Conducted?

The non-stress test is generally conducted during the third trimester, usually one month prior to the due date. Non-stress test is preferably done after the 28th week of gestation in light of the fact that, if it is conducted earlier, the fetus is not developed well enough to react to the test. It is usually repeated once or twice a week depending on the circumstances. This test can take anywhere around 20 – 40 minutes.

What Is The Purpose Of Non-Stress Test?

The aim of the non-stress test is to evaluate the fetal heart rate with respect to the fetal movement. The basic concept of the non-stress test is that the optimum level of oxygen is essential for healthy fetal activity and to keep the fetal heart rate within normal ranges. Thus, less active fetus indicates inadequate oxygen supply. This will act as a red flag for umbilical cord or placental issues. This test can also indicate other reasons for fetal distress.

When Is The Non-Stress Test Conducted?

The non-stress test is generally suggested if:

• The mother possesses Polyhydramnios (increased level of amniotic fluid) or Oligohydramnios (low level of amniotic fluid)
• The mother has health conditions like gestational hypertension or diabetes
• If the baby shows signs of IUGR (Intra Uterine Growth Restriction)
• The mother has any medical problem, which could jeopardize the health of the unborn baby
• The mother has had a previous experience of unreasoned pregnancy loss during the second half of pregnancy. If this is the reason, the non-stress test is conducted without much delay, around 28th week of gestation
• If the baby has a health issue which demands continuous monitoring
• The mother has to undergo certain invasive test like amniocentesis in the course of pregnancy, the doctor suggests a non-stress test to ensure the health of the baby
• The pregnancy is overdue as the mother has crossed the due date and there are no significant signs of labor
• Any reason to believe that the placenta is not working properly

What Is The Procedure Of The Non-Stress Test?

• You will be asked to eat a good meal, which may urge the baby to move (no scientific proof, though)
• You will be asked to urinate before the procedure, as it will last around 20 – 40 minutes and as you are in the second half of your pregnancy, it will be hard to hold the urge to urinate
• Throughout the procedure, you will be lying on your left side
• Two belts will be strapped to the abdomen, one monitoring the heart rate and movement of the fetus and other one monitoring uterine contractions
• If the baby is not moving, there are chances that the baby is not awake and you will either be asked to drink water or fruit juice to wake the baby or the nurse will use a buzzer to wake him up
• Your contractions are recorded on the paper and the fetal heartbeat is viewed on an electronic screen

How Can I Interpret The Results Of The Non-Stress Test?

The Results are available immediately and the result will either be ‘reactive’ or ‘nonreactive’.
1. Reactive result: The reactive results mean the baby’s heart beats at least 15 beats more than the resting heart rate. It also indicates that the baby will remain healthy and out of danger for at least 3 to 7 days after which the test is repeated
2. Non-Reactive result: The nonreactive result means the baby’s heartbeat is not increasing according to its movement. Moreover, the uterine contraction may also not be at a normal pace. Though this doesn’t prove that the baby is in danger, further tests like Biophysical Profile or Contraction Stress Test are conducted to collect more details and ensure the fetus health. Nevertheless, a nonreactive result could show that your child isn’t getting enough oxygen or that there are issues with the placenta resulting in fetal distress

If the doctor thinks the baby is no longer safe in the womb, the labor is induced.

Is There Any Risk Associated With The Non-Stress Test?

No. As the non-stress test is noninvasive, it possesses no danger for mother and the child. The term “non-stress” indicates that nothing is done to place stress on the fetus during the test.