Biophysical profile | |
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Synonyms | BPP |
Purpose | prenatal evaluation ultrasound |
A biophysical profile (BPP) is a prenatal ultrasound evaluation of fetal well-being involving a scoring system, [1] with the score being termed Manning's score. [2] It is often done when a non-stress test (NST) is non reactive, or for other obstetrical indications.
The "modified biophysical profile" consists of the NST and amniotic fluid index only.
The BPP has five components: four ultrasound (US) assessments and an NST. The NST evaluates fetal heart rate and response to fetal movement. The five discrete biophysical variables are:
Parameter | Normal (2 points) | Abnormal (0 points) |
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NST/Reactive FHR | At least two accelerations in 20 minutes | Less than two accelerations to satisfy the test in 20 minutes |
US: Fetal breathing movements | At least one episode of > 30s or >20s [3] in 30 minutes | None or less than 30s or 20s [3] |
US: Fetal activity / gross body movements | At least three discrete body/limb movement in 30 minutes (episodes of active continuous movement considered a single movement. | Less than three or two [3] movements |
US: Fetal muscle tone | At least one [3] episode of active extension with return to flexion of fetal limb(s) or trunk, opening and closing of hand considered to be normal tone. | Either slow extension with return to partial flexion or movement of limb in full extension or absent fetal movement. |
US: Qualitative AFV/AFI | At least one vertical pocket > 2 cm in the vertical axis or AFI of 5 cm | Largest vertical pocket </= 2 cm, or AFI </= 5 cm |
Use of vibroacoustic stimulation to accelerate evaluation has been described. [4]
Each assessment is graded either 0 or 2 points and then added up to yield a number between 0 and 10. A BPP of 8 or 10 is generally considered reassuring. A BPP normally is not performed before the second half of a pregnancy since fetal movements do not occur in the first half. [5] The presence of these biophysical variables implies absence of significant central nervous system hypoxemia/acidemia at the time of testing. By comparison, a compromised fetus typically exhibits loss of accelerations of the fetal heart rate (FHR), decreased body movement and breathing, hypotonia, and, less acutely, decreased amniotic fluid volume.
BPP | Recommended management |
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≤2 | |
4 |
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6 |
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≥ 8 |
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Amniocentesis is a medical procedure used primarily in the prenatal diagnosis of genetic conditions. It has other uses such as in the assessment of infection and fetal lung maturity. Prenatal diagnostic testing, which includes amniocentesis, is necessary to conclusively diagnose the majority of genetic disorders, with amniocentesis being the gold-standard procedure after 15 weeks' gestation.
Obstetric ultrasonography, or prenatal ultrasound, is the use of medical ultrasonography in pregnancy, in which sound waves are used to create real-time visual images of the developing embryo or fetus in the uterus (womb). The procedure is a standard part of prenatal care in many countries, as it can provide a variety of information about the health of the mother, the timing and progress of the pregnancy, and the health and development of the embryo or fetus.
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The amniotic fluid is the protective liquid contained by the amniotic sac of a gravid amniote. This fluid serves as a cushion for the growing fetus, but also serves to facilitate the exchange of nutrients, water, and biochemical products between mother and fetus.
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