What is Biophysical Profile ?
The biophysical profile (BPP) is a 30-minute long ultrasound assessment to assess fetal(unborn baby’s) well-being coupled with a fetal heart rate tracing. The elements are a non-stress test, assessment of fluid index, fetal breathing movements, total body movements, and limb tone demonstrated by flexion and extension of the limbs. The modified BPP is a shortened study that involves a non-stress test (NST) and amniotic fluid index (AFI).
The biophysical profile (BPP) is based on the concept that fetal breathing, movement and tone are mediated by neurological pathways and therefore reflect the fetal CNS(central nervous system) status at the time of the examination. Amniotic fluid level is a measure of fetal oxygenation status or placental function. The addition of the evaluation of the fetal heart rate variability (NST) to the BPP increases the sensitivity for acute status changes.
When is a biophysical profile test needed?
A biophysical profile is often done if there is a concern about your baby’s health. For instance, it might be done if there is decreased fetal movement or a fetal growth problem, or your pregnancy goes past due dates or if any high risk factor is present in your pregnancy.
If your obstetrician suggests a biophysical profile, it doesn’t mean anything is wrong with your baby. It is done to to check the health of your baby in the womb.
It is generally done in third trimester, usually after 32 weeks of pregnancy.
What is to be done prior to exam?
No special preparations are required. You are expected to take a prior appointment. You may be advised to hydrate well and eat a meal just before the test in the hope that eating will stimulate your baby to move around more. (Although there’s no hard evidence that this works, it can’t hurt.)
What will happen during the examination?
The scan will be performed in dimly lit room and you would be asked to lie on a flat couch. Clear(perhaps cold) ultrasound gel will then be applied and the ultrasound specialist will commence the exam. To get optimum views of your baby, slight pressure may have to be applied.
The ultrasound is done to observe your baby’s body movements, muscle tone, and breathing movements, and to measure the amount of amniotic fluid surrounding them.
Each of the four components – body movements, muscle tone, breathing movements, amniotic fluid – is assigned a score of either 0 (abnormal) or 2 (normal). These are added up for a total score ranging from 0 to 8.
What does the scoring mean?
A score of eight with good amniotic fluid is regarded as “reassuring” which is normal.
A score of six indicates that there may be problems and additional testing is needed. This could mean that you require an NST( a test where fetal heart tracing is obtained and studied) or a repeat testing in 12-24 hours. Decision for delivery may be made
If you score four or less, your obstetrician may need to deliver the baby right away. In some cases, further testing is needed and delivery can be delayed until absolutely necessary.
Closer monitoring is always needed if your amniotic fluid is too low, even if your other scores are normal.
Benefits:
It is a safe and painless study.
It is an indicator of fetal wellbeing reflecting the blood pH.
It can help in decision of delivery when required.
Limitations:
It is not very reliable before 32 weeks of gestation.
Fetal sleep cycles, as well as a number of medications like narcotics, magnesium sulfate, corticosteroids, and tocolytics can affect the study.
In some obstetric patients, it is very uncomfortable to lie supine. For these cases, this positioning is needed only for the amniotic fluid assessment, and then reposition the patient in a more comfortable pose for the remainder of the BPP.
What happens after the examination?
You would usually receive the printed report on the same day.