 A non-stressed test, NST, is a test to assess fetal well-being. It measures fetal heart rate and response to movement in the third trimester to ensure that the baby is doing well. On the day of the test, you will be advised to have snacks, water or juice as this helps in better baby movements. You must void urine before the test. This is a painless, non-invasive procedure performed by the nurse and usually takes about 20 minutes. You are required to lie down comfortably on the procedure bed. The test is done by tying two belts with sensors around your belly which detects fetal heart rate and uterine pressure. You will be given a marker to mark the fetal movements. You will need to press the marker button each time you feel the baby move. The graph will be assessed by your doctor during consultation.