Each area that's evaluated during a biophysical profile is given a score of 0 or 2 points, depending on whether specific criteria were met. A score can be given as soon as the biophysical activity is observed. For example:
- Fetal heart rate. Results of this portion of the test (nonstress test) are called reactive or nonreactive. If your baby's heartbeat accelerates twice or more within a 20-minute period, the results are considered reactive and 2 points will be given. If not enough accelerations occur within a 40-minute period, the results are considered nonreactive and 0 points will be given. Keep in mind that nonreactive results might occur because your baby was asleep during the test.
- Fetal breathing. If your baby displays at least one episode of rhythmic breathing for 30 seconds or more within 30 minutes, 2 points will be given. If your baby's breathing doesn't meet the criteria, 0 points will be given.
- Fetal movement. If your baby moves his or her body or limbs three times or more within 30 minutes, 2 points will be given. If your baby's movements don't meet the criteria, 0 points will be given.
- Fetal muscle tone. If your baby moves a limb from a bent position to an extended position and quickly back to a bent position, 2 points will be given. If your baby's muscle tone doesn't meet the criteria, 0 points will be given.
- Amniotic fluid level. The ultrasound technician will look for the largest visible pocket of amniotic fluid. To obtain a score of 2 points, the pocket must be a certain size. If your amniotic fluid level doesn't meet the criteria, 0 points will be given.
The individual scores are then added together for a total score. Typically, a score of 8 to 10 is reassuring. If you receive a score of 6, your health care provider will likely repeat the test within 24 hours. Another score of 6 or a lower score might lead your health care provider to recommend further testing or an early or immediate delivery.
In addition, if your health care provider finds that you have a low amount of amniotic fluid, you'll need further testing and might need to deliver your baby early — regardless of your overall score.
Keep in mind that certain factors can affect the results of a biophysical profile, including the use of corticosteroids to speed your baby's lung maturity and the presence of an infection. Smoking or taking certain medications also can affect the baby's heart rate.
Be sure to discuss the results of your biophysical profile with your health care provider to fully understand what they might mean for you and your baby.
March 05, 2015
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