Health & Pregnancy

What Affects the Test

Reasons you may not be able to have the test or why the results may not be helpful include:

• Smoking cigarettes or using other tobacco products and drinking or eating large amounts of caffeine (such as from several cups of strong coffee), which can falsely raise your baby's heart rate.
• Extra noises such as your heartbeat or your stomach rumbling.
• Your baby is sleeping during a nonstress test.
• Problems with the placement of the external monitoring device. These problems may include:
  • Your baby is moving a lot during the test.
  • You are pregnant with more than one baby, such as twins or triplets.
  • You are overweight.

What To Think About

• Not everyone feels the same about fetal monitoring.
  • Some mothers think that fetal heart monitoring is not needed and interferes with the natural birthing process.
  • Other mothers think that fetal heart monitoring is reassuring. This may be true if they had problems with earlier pregnancies.
• Fetal monitoring can't predict every type of problem, such as birth defects. Normal fetal heart monitoring test results do not mean that your baby is healthy.
• Continuous monitoring during labor is more likely to be useful for high-risk pregnancies. Intermittent fetal heart monitoring during labor is as effective as continuous monitoring in low-risk pregnancies.
• If your baby appears to be having problems, sometimes a blood sample is taken from a small blood vessel (capillary) in his or her scalp. The blood sample can help determine if your baby is receiving enough oxygen.
• Your baby may move more if you eat or drink juice before having a nonstress test. This may make the test results more useful.
• Sometimes other methods (such as ringing a bell near the uterus) are used to cause changes in your baby's heart rate.
• External fetal heart monitoring is used during other tests of fetal health, such as a nonstress test, contraction stress test, and biophysical profile. For more information, see the topics Contraction Stress Test and Biophysical Profile (BPP).

Other Places To Get Help

Organization

Related Information

• Biophysical Profile (BPP)
• Fetal Ultrasound
• Pregnancy