Tests to Evaluate Baby's Well Being

The biophysical profile (BPP) is a specific ultrasound that allows fetal visualization of several detailed dimensions of fetal well being, and to measure them against “healthy” standards. The measurements include fetal breathing movements, gross body movements and tone, fetal heart rate, and the volume of amniotic fluid.  A normal BPP can reassure that the fetus is not stressed at the time of the exam. In combination with an NST, a good indication of the health of the fetus is achieved.  If the BPP is not normal, it is an indication that there are stressors on the baby that need further evaluation.  This could include a maternal fetal medicine consult and/or admission to the hospital to be monitored closely.

Amniocentesis is a procedure in which a small amount of amniotic fluid surrounding the fetus is removed for evaluation.  In addition to testing for chromosomal abnormalities, amniocentesis can help determine the maturity of lungs of the fetus, the cause of unknown fever in the mother as well as detect infection in pregnancy.

The non-stress test (NST) involves the use of a fetal monitor which is attached to the mother’s abdomen. The device has two monitors to measure the fetal heart rate and uterine contractions. The fetus’ movement, heart rate and “reactivity” of heart rate are measured for 20-30 minutes.  During movement, healthy babies respond with an increased heart rate. If the baby does not move, it does not necessarily indicate a problem; the baby could be asleep, or responding to certain medication his/her mother is taking. Indications for NSTs typically performed after 28 weeks are: decreased fetal movement, pregnancy past its due date, monitoring how fetus is handling a high risk pregnancy and to indicate other types of fetal distress.

NST results are classified either as “reactive”- a reassuring sign of fetal well being, or non-reactive, indicating the need for more observation, and/or additional testing. It is important to note that the gestational age of the fetus can also affect the outcome of an NST. Only 50% of NSTs are reactive in weeks 24 –32 of pregnancy.

Depending on how you are doing with your pregnancy, it is entirely possible for you to never have an NST or to have regular NSTs for high risk monitoring.

An ultrasound may be performed as part of Maternal Screening for Birth Defects, especially if your screening blood work indicates you are at risk. You might have ultrasound at other times during your pregnancy to assess items such as the number of babies, baby’s size (right for his/her age), internal organs, amniotic fluid surrounding the baby, and location of the placenta.   Ultrasound can detect many, but not all abnormalities. Finding an abnormality depends on many factors, including the age and position of the baby, as well as the size and type of abnormality. 

For most pregnant women, ultrasound assures them that their baby is healthy and all is well. Sadly, for a few, the ultrasound will find signs that all is not normal. Your clinician will review your results with you and make recommendations on next steps when needed.

There are ways for a pregnant woman to monitor the activity level of her unborn baby by becoming aware of their own bodily sensations. Fetal movements or quickening generally can be felt between 18-20 weeks for first-time mothers, and 16-18 weeks for those with previous pregnancies.

Periodic monitoring can help a mom become aware of her baby’s activity level and provide a baseline for measuring future activity.  As you approach the end of pregnancy, it is important that you continue to feel active periods of fetal movement, especially if you have had a complication of pregnancy like hypertension or diabetes. Many clinicians have different formulas for what they consider a “normal” amount of movement.

Certainly every baby will be different in terms of the amount or quality of movements, but most healthy babies move frequently. The fetus has active periods and rest periods although most of the time the fetus is asleep.  You may notice that your baby is more active after a meal or when you lie down. To do a fetal movement count, choose the baby's most active time of day, and repeat this procedure at the same time every day. Start the clock and see how long it takes you to record 10 movements – twists, pokes, kicks and turns.

If the fetal activity seems slower than usual, have something to eat or drink, walk around for 10 –15 minutes, then lay down on your left side and see if the movements have picked up. Your baby should move a minimum of 10 times in four hours – your clinician may have even stricter guidelines. If you have any concerns regarding a decrease in the quantity or quality of fetal movements, consult your physician or midwife without delay.