Biophysical Profile (BPP): Purpose, the Five Parts, Scoring and Results

Written and medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: November 2026 · How we review

Quick Answer: What is a biophysical profile?

A biophysical profile (BPP) is a prenatal test that checks a fetus's health, usually after 32 weeks. It combines an ultrasound that scores body movement, muscle tone, breathing movements and amniotic fluid with a nonstress test of the fetal heart rate, for a maximum score of 10. It takes 30 to 40 minutes and carries no risk.

What the research says

• The ultrasound-only profile is reassuring in high-risk pregnancies. In 985 women with conditions such as diabetes, hypertension and lupus, 3,981 ultrasound biophysical profiles done weekly from 32 weeks had a test-positive rate of 1.6% per woman and a stillbirth rate of only 0.3% after a normal result. (Zafman et al., Obstetrics & Gynecology, 2018) [2]

• Trial evidence on outcomes is still limited. A Cochrane review of 5 randomized trials found no clear difference in perinatal deaths or low Apgar scores with the biophysical profile versus other monitoring, but the two highest-quality trials (280 women) suggested more cesarean deliveries (RR 1.60), so the authors called for more research. (Lalor et al., Cochrane Database of Systematic Reviews, 2008) [3]

Key takeaways

• A biophysical profile checks fetal breathing, movement, muscle tone and amniotic fluid by ultrasound, usually with a nonstress test. [1]

• It is typically done after 32 weeks in higher-risk pregnancies, such as those with diabetes, high blood pressure or reduced fetal movement. [1]

• A score of 8 with normal fluid is reassuring; 6 may mean repeating the test within 12 to 24 hours; 4 or less may mean delivery is needed soon. [1]

• The test is painless, carries no risk and takes 30 to 40 minutes at most. [1]

• Results are usually available the same day. [1]

What is a biophysical profile?

A biophysical profile is a diagnostic test that uses ultrasound, often together with a nonstress test, to evaluate how a fetus is doing in the last part of pregnancy. It can be done as a complete profile or as a modified profile. [1]

The five components of a biophysical profile.

The five parts of the test

Component	How it is checked	What earns 2 points
Nonstress test	Fetal heart monitor	Two or more heart rate accelerations within 20 minutes
Body movement	Ultrasound	Three or more separate body or limb movements in 30 minutes
Muscle tone	Ultrasound	At least one episode of flexing and extending a limb, or opening and closing a hand
Breathing movements	Ultrasound	At least one episode of continuous breathing lasting 30 seconds or more
Amniotic fluid	Ultrasound	At least one pocket measuring 2 cm deep and 1 cm across

Sources: [1]

Who needs a biophysical profile?

Common reasons for a biophysical profile.

Your provider may order the test if your pregnancy is high risk or goes past 40 weeks, or if you have: [1]

• High blood pressure, preeclampsia, lupus, kidney disease or low platelets [1]

• Diabetes before pregnancy or gestational diabetes [1]

• Decreased fetal movement [1]

• A previous stillbirth or other poor pregnancy outcome [1]

• Twins or triplets [1]

• Possible intrauterine growth restriction [1]

• Too much or too little amniotic fluid (polyhydramnios or oligohydramnios) [1]

• Rh-negative blood, age 35 or older at delivery, or a BMI of 30 or higher [1]

What happens during a biophysical profile?

For the ultrasound, you lie down or recline while a transducer on your belly sends sound waves that become images. For the nonstress test, a belt with a sensor around your belly records the fetal heart rate; sometimes a second monitor records contractions. The nonstress test usually takes about 20 minutes but can last up to 40 if the fetus is asleep, in which case your provider may use a buzzer to wake it. [1]

The whole biophysical profile takes no longer than 30 to 40 minutes. It is painless and carries no risk to you or the fetus. [1]

How is a biophysical profile scored?

What biophysical profile scores mean.

Each of the four ultrasound components scores 0 or 2 points, never 1, for a maximum of 8. If the nonstress test is included, two heart rate accelerations within 20 minutes add 2 more points. [1]

Score	What it means
8 (with normal amniotic fluid)	Reassuring
6	Possible problems; the test may be repeated in 12 to 24 hours, or early delivery considered
4 or less	Delivery may be needed right away

Sources: [1]

Low amniotic fluid calls for closer monitoring even when the other scores are normal. An abnormal result does not always mean there is a problem, because factors such as recent corticosteroid treatment can change fetal breathing and movement for several days. [1]

What are the limits of a biophysical profile?

The test is less reliable before 32 weeks, and it may need to be repeated. [1] Research in high-risk pregnancies shows that a normal ultrasound profile is followed by stillbirth only rarely, [2] but randomized trials have not yet proven that the test improves outcomes compared with other monitoring, and it may increase cesarean deliveries. [3]

What happens after the test?

Results are typically available the same day, and your obstetrician usually explains them at an appointment shortly afterward. [1]

When should you call a doctor?

Call your provider right away if you notice decreased fetal movement, vaginal bleeding, fluid leaking, severe headache or vision changes, whether or not you have a biophysical profile scheduled.

Conclusion

A biophysical profile is a safe, painless way to check on a fetus in the last weeks of a higher-risk pregnancy. It combines ultrasound measures of movement, tone, breathing and fluid with the nonstress test, and a score of 8 with normal fluid is reassuring. [1]

Lower scores guide your care team toward repeat testing, closer monitoring or delivery. Ask your provider what your score means for your pregnancy. [1]

Keep learning: Read our guide to the nonstress test to understand the heart rate part of the biophysical profile.

Frequently asked questions

What is a biophysical profile?

A prenatal test that uses ultrasound and a nonstress test to check fetal breathing, movement, muscle tone, amniotic fluid and heart rate.

When is a biophysical profile done?

Usually after 32 weeks of pregnancy, when the test is most reliable.

Who needs a biophysical profile?

People with high-risk pregnancies, such as those with diabetes, high blood pressure, reduced fetal movement, twins or a pregnancy past 40 weeks.

How long does a biophysical profile take?

No longer than 30 to 40 minutes.

Is a biophysical profile safe?

Yes. It is painless and carries no risk to you or the fetus.

What is a normal biophysical profile score?

A score of 8 with normal amniotic fluid is reassuring; with the nonstress test the maximum is 10.

What does a biophysical profile score of 6 mean?

Possible problems. The test may be repeated in 12 to 24 hours, or early delivery may be considered.

What does a score of 4 or less mean?

Delivery may be needed right away.

What is a modified biophysical profile?

A shorter version that combines the nonstress test with a check of amniotic fluid.

Can steroids affect a biophysical profile?

Yes. Corticosteroids can increase fetal breathing and reduce movement for several days.

Related Reading

Nonstress Test (NST): Why It's Done, What to Expect and Reactive vs Nonreactive Results explains the fetal heart rate test that forms part of the biophysical profile.

Pregnancy Ultrasound: Why It's Done, When You'll Have One, What to Expect and Results covers how ultrasound is used throughout pregnancy.

Preeclampsia: Symptoms, Causes & What Helps — A Complete Guide describes a condition that often leads to biophysical profile testing.

Gestational Diabetes: Symptoms, Causes, Risks & Treatment — Complete Guide explains another common reason for fetal monitoring.

What Is Oligohydramnios? Causes, Signs, and Treatment covers low amniotic fluid, one of the scored components.

Intrauterine Growth Restriction (IUGR): Causes, Risks, and Management describes slow fetal growth, a reason for closer monitoring.

Fetal Heart Rate Monitoring: Normal Range, Types and Decelerations explains how a baby's heart rate is monitored in pregnancy and labor.

Contraction Stress Test: How It Works and What Results Mean explains the late-pregnancy test of how the baby handles contractions.

References

1. Cleveland Clinic. Biophysical Profile: Purpose, Test & Score. Cleveland Clinic. Last updated December 19, 2022. https://my.clevelandclinic.org/health/diagnostics/21013-biophysical-profile

2. Zafman KB, Bruck E, Rebarber A, et al. Antenatal Testing for Women With Preexisting Medical Conditions Using Only the Ultrasonographic Portion of the Biophysical Profile. Obstet Gynecol. 2018;132(4):1033-1039. PMID 30130352. https://doi.org/10.1097/AOG.0000000000002811

3. Lalor JG, Fawole B, Alfirevic Z, et al. Biophysical profile for fetal assessment in high risk pregnancies. Cochrane Database Syst Rev. 2008;(1):CD000038. PMID 18253968. https://doi.org/10.1002/14651858.CD000038.pub2

Medical disclaimer

This article is for general education only and does not replace advice from a qualified healthcare professional. Talk to your doctor about your own diagnosis and treatment, and seek emergency care right away for severe or sudden symptoms.