A non-stress test (NST) is a common prenatal test used to check on a baby’s health. The term “non-stress” refers to the fact that nothing is done to place stress on the baby during the test when the baby’s heart rate and movement, and the mother’s uterine contraction are monitored. An NST may be done after 28 weeks of pregnancy when there is doubt about the baby’s well-being. Indications include:
1) Decreased fetal movement;
2) Intrauterine growth restriction (IUGR);
3) Prolonged pregnancy >40 weeks;
4) Gestational diabetes with other complications e.g. fetal macrosomia (big baby), polyhydramnios, poor control of diabetes etc.;
5) Previous stillbirth.
During an NST, two straps with monitors are put on the mother’s abdomen to monitor the baby’s heart rate and the presence of uterine contractions. The mother is asked to press on a button when she feels a fetal movement. If there is no or too little fetal movement, the midwife may ask the mother to change her position, gently rock the mother’s abdomen, or give the mother a candy. The aim is to wake up the baby. The test takes around 20 to 30 minutes. The test result is classified as “reactive” (“reassuring”) or “non-reactive” (“non-reassuring”). While a reactive NST is reassuring, a non-reactive NST does not always mean that the baby is at risk, but it warrants further testing such as a biophysical profile.
The clinic is equipped with a cardiotocograph machine for performing NSTs. Our experienced midwife monitors the mother during the NST process. Any abnormality in the NST can be identified and the doctor is notified promptly so that appropriate course of action can be taken.