Reference — Maternal-Newborn
Antepartum Fetal Testing Reference
The criteria you have to keep straight: which result is the good one for each test. Reactive NST and negative CST both reassure; the BPP scores out of 10.
Educational use only. Interpretation thresholds vary slightly by reference and gestational age; follow current obstetric guidelines and your facility protocol. This material supports nursing education and exam review. It is not medical advice and is not a substitute for clinical judgment, institutional policy, or medical direction. Always follow facility protocols and current provider orders.
Tests at a Glance
| Test | What it measures | Reassuring (good) result | Concerning result |
|---|---|---|---|
| Nonstress test (NST) | External FHR monitoring for accelerations with fetal movement; no contractions | REACTIVE: ≥2 accelerations (≥15 bpm above baseline × ≥15 sec) in 20 min | Nonreactive: criteria not met (often fetal sleep — try stimulation/extend, then BPP/CST) |
| Contraction stress test (CST) | FHR response to contractions (nipple stimulation or oxytocin) | NEGATIVE: no late decelerations with contractions | Positive: late decelerations with most contractions = uteroplacental insufficiency |
| Biophysical profile (BPP) | Ultrasound: breathing, gross movement, tone, amniotic fluid + the NST (each 0 or 2) | 8–10: reassuring | 6: equivocal (repeat/deliver per context); ≤4: concerning → delivery considerations |
| Amniotic fluid index (AFI) | Ultrasound sum of fluid pockets in 4 quadrants; reflects chronic placental function | Normal ~5–25 cm | <5 cm oligohydramnios (insufficiency); >25 cm polyhydramnios |
BPP — The 5 Components
Each scores 2 (present) or 0 (absent), max 10: fetal breathing movements, gross body movements, fetal tone, amniotic fluid volume, and the NST (reactivity). A “modified BPP” uses just the NST + AFI as a quicker screen.
Memory aid — “Test the baby, MAN!”: Tone, Breathing, Movement, Amniotic fluid, NST.
NCLEX Pearls
- ✦Reactive NST and negative CST are BOTH the reassuring results — the worrying-sounding words are the good ones.
- ✦Positive CST = late decelerations = uteroplacental insufficiency (bad); it's the test of placental reserve.
- ✦BPP 8–10 reassuring, 6 equivocal, ≤4 concerning; amniotic fluid is the component reflecting chronic status.
- ✦Oligohydramnios (low AFI) suggests placental insufficiency or renal/outflow problems; polyhydramnios has GI/neuro and diabetic associations.
- ✦A nonreactive NST is most often a sleeping fetus — use vibroacoustic stimulation before assuming compromise.
Related Resources
Standards & sources
Fact-checked Jun 20, 2026This page is written to align with American College of Obstetricians and Gynecologists (ACOG) · AWHONN · American Academy of Pediatrics (AAP) — newborn. It is an educational summary, not a citation of any single document — always verify specific doses, values, and protocols against current guidelines and your facility policy. How we source content →