When should a Biophysical Profile (BPP) be repeated if the initial result is 6/8 and the follow-up result is 8/8?

Management of Biophysical Profile (BPP) After Improvement from 6/8 to 8/8

When a BPP improves from 6/8 to 8/8, repeat testing should be performed in 7 days, as a normal BPP score (8/8 or 10/10) provides strong reassurance of fetal well-being for one week with a negative predictive value exceeding 99.9%. 1

Understanding BPP Scoring and Interpretation

A BPP consists of four ultrasound components (fetal breathing movements, body/limb movements, fetal tone, and amniotic fluid volume), each scored as either 0 or 2:

• Score 8/8: Normal, indicates well-compensated fetus
• Score 6/8: Equivocal, requires closer monitoring
• Score ≤4/8: Abnormal, indicates potential fetal compromise

Initial 6/8 Score (Equivocal)

• A score of 6/8 is considered equivocal and typically requires repeat testing within 24 hours 1
• This score suggests potential early signs of fetal compromise but is not definitively abnormal

Follow-up 8/8 Score (Normal)

• A normal score (8/8) strongly indicates a well-compensated fetus with minimal risk of adverse outcomes
• The likelihood of stillbirth occurring within one week of a normal test result is extremely low (0.8 per 1,000) 1

Recommended Management Algorithm

1. After improvement from 6/8 to 8/8:

   • Return to standard testing frequency of once weekly 1
   • The normal BPP result (8/8) is valid for up to one week

2. Special considerations for more frequent testing:

   • If the pregnancy has additional high-risk factors (FGR, oligohydramnios, maternal hypertension), consider twice-weekly testing 2, 1
   • For fetuses with absent or reversed end-diastolic flow in umbilical artery, more frequent monitoring is warranted 2

3. Monitoring components to include in follow-up:

   • Complete BPP (all four components)
   • Consider adding NST for a modified BPP if available 2
   • Pay particular attention to the component(s) that were abnormal in the initial 6/8 score

Important Clinical Considerations

• The American College of Radiology recommends that a normal BPP score provides strong reassurance of fetal well-being for the next 7 days 1
• Doppler ultrasonography and BPP effectively stratify high-risk fetuses into risk categories, but they do not always show a consistent relationship with each other 3
• Fetal deterioration appears to be independently reflected in different testing modalities, suggesting value in combining assessment approaches 3

Pitfalls to Avoid

• Do not rely solely on a single normal test result without considering the overall clinical picture and risk factors
• Avoid overconfidence in normal test results, as acute deterioration can still occur despite previous normal testing 1
• Never ignore maternal perception of decreased fetal movement despite normal testing results 1
• Be aware that different definitions of amniotic fluid adequacy exist, which can affect BPP scoring and interpretation 4

The improvement from an equivocal score (6/8) to a normal score (8/8) indicates resolution of the concerning findings and allows return to standard weekly monitoring, provided there are no other high-risk factors requiring more frequent assessment.