The tests below are very good at identifying healthy fetuses. Often, if the test is abnormal, there is nothing wrong with the fetus. If the baby is preterm and a test comes back abnormal, a second test is often done to determine if the fetus is healthy. Sometimes all three tests will be used to determine if a preterm fetus is healthy. If the due date is close, or has already passed, an abnormal test is a reason for delivery.
Vaginal delivery is almost always safe, even with abnormal tests.
Healthy fetuses will increase their heart rate with movement. There are specific criteria that obstetric providers use to evaluate the heart rate elevations. If the criteria are met, there is very little likelihood that the fetus will have trouble over the following 3-4 days. A belt with a fetal monitor is attached to the women s abdomen, over the fetal heart. The woman is asked to push a button every time the fetus moves.