From the Guidelines
A biophysical profile (BPP) consists of four main components that assess fetal well-being during pregnancy, including fetal breathing movements, fetal body movements, fetal tone, and amniotic fluid volume, with an optional fifth component being the non-stress test (NST) 1. The components of the BPP are designed to evaluate different aspects of fetal health and development.
- Fetal breathing movements assess the fetus's practice breathing efforts, which are essential for lung development and function.
- Fetal body movements indicate neurological development and overall fetal activity.
- Fetal tone is evaluated by observing limb and body flexion and extension, which reflects the fetus's muscular and nervous system development.
- Amniotic fluid volume, often measured as the amniotic fluid index (AFI) or deepest vertical pocket, reflects placental function and kidney development, as well as the overall health of the fetus. Each component of the BPP is scored 0 or 2 points, with a maximum total score of 8 or 10 points if the NST is included 1. The BPP is a crucial tool for assessing fetal well-being, particularly in high-risk pregnancies, and a score of 8 or 10 typically indicates a healthy fetus, while lower scores may prompt additional testing or delivery decisions 1. The BPP is commonly performed in high-risk pregnancies, including those with decreased fetal movement, intrauterine growth restriction, or maternal conditions like hypertension or diabetes, usually after 28 weeks gestation when fetal movements are well established 1. The most recent and highest quality study on this topic, published in 2019, supports the use of the BPP as a mainstay of fetal well-being evaluation, particularly in the setting of fetal growth restriction 1.
From the Research
Components of Biophysical Profile
The biophysical profile (BPP) is a test used to assess fetal health and well-being. The components of the BPP include:
- Fetal movement: assessed through ultrasound to evaluate the fetus's ability to move its limbs and body 2, 3, 4, 5, 6
- Fetal tone: evaluated through ultrasound to assess the fetus's muscle tone 2, 3, 4, 5, 6
- Fetal breathing movements: assessed through ultrasound to evaluate the fetus's ability to breathe 2, 3, 4, 5, 6
- Fetal heart rate reactivity: evaluated through nonstress test monitoring to assess the fetus's heart rate in response to movement 2, 3, 5, 6
- Amniotic fluid volume: estimated through ultrasound to assess the amount of fluid surrounding the fetus 2, 3, 4, 5, 6
Importance of Biophysical Profile Components
Each component of the BPP provides valuable information about fetal health and well-being. The combination of these components helps to reduce the false-positive rate associated with single-parameter testing methods 3. The BPP is particularly useful in monitoring high-risk pregnancies and predicting perinatal death 5.