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Your obstetrician says you need a non-stress test, and you're left wondering what it is and why you need one. Doctors order non-stress tests during pregnancy for a variety of reasons, including reduced fetal movement or the suspicion of poor placental functioning, according to the American Pregnancy Association. This test lets your obstetrician determine if your baby isn't getting enough oxygen or is in distress.
Risks and Reasons
There isn't just one specific reason why your doctor would order a non-stress test. Among the reasons are low fetal movement or a pregnancy deemed high-risk due to conditions such as diabetes or high blood pressure, according to the website BabyCenter. Some doctors may also order the test if you are past your due date, your baby isn't growing on the typical track or you have too much amniotic fluid.
During the Test
Non-stress tests are non-invasive, which means that they involve no surgery and no medical instruments will enter your body. You will have two monitors placed around your belly. If you're having contractions, one monitor will record them. The other monitor tracks your baby's movements and heart rate. If your baby isn't moving much or at all, your doctor or nurse may use a buzzer to wake her up and get her kicking again. The time required ranges from 20 to 40 minutes, notes the Johns Hopkins Department of Gynecology and Obstetrics website.
Measurements and Results
A non-stress test measures your baby's heart rate in response to it's own movements, according to the American Pregnancy Association. A baby who is getting an adequate amount of oxygen typically has a heart rate that rises during movement. If your baby doesn't move or his heart doesn't beat faster during movement, this doesn't always indicate a problem, notes Johns Hopkins Medicine. A nonreactive result signals the potential for a problem and that further testing is needed.
The American Pregnancy Association notes that a non-stress test poses no risk for the mother or the baby. Likewise, there are no known side effects for either of you. This test is often a first step in determining of a problem exists, as it is a safe and easy option to measure how you're baby is doing. The University of Pittsburgh Medical Center explains on its website that a non-stress test may be ordered once or twice a week or even more often.