sFlt-1/PlGF Ratio (Preeclampsia Rule-out / Rule-in)
sFlt-1/PlGF ratio (Zeisler 2016 PROGNOSIS; Verlohren 2014): a Roche Elecsys biomarker for suspected preeclampsia; ≤ 38 rules it out for the next week, with phase-specific rule-in thresholds (≥ 85 early, ≥ 110 late).
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- sFlt-1/PlGF ratio
- 25
- Gestational phase
- Late-onset (≥ 34 weeks) — rule-in ≥ 110
Result: sFlt-1/PlGF 25 — ≤ 38: preeclampsia ruled out for the next week (NPV ≈ 99.3%).
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What the result means
- Rule-out
- A ratio ≤ 38 rules preeclampsia out for the next week (NPV ≈ 99.3%, Roche Elecsys assay). A rule-out biomarker that safely reduces unnecessary admissions.
- Rule-in
- > 38 flags elevated short-term risk; the gestational-phase rule-in thresholds are ≥ 85 (early-onset < 34 weeks) and ≥ 110 (late-onset ≥ 34 weeks). Not a delivery or magnesium order.
What you enter
- sFlt-1/PlGF ratio
- Gestational phase (early < 34 wk or late ≥ 34 wk)
How this is calculated
Zeisler H, Llurba E, Chantraine F, et al. Predictive value of the sFlt-1:PlGF ratio in women with suspected preeclampsia. N Engl J Med. 2016;374(1):13-22. Phase-specific cut-points: Verlohren S, et al. Hypertension. 2014;63(2):346-352. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.