Fetal CPR Calculator

Fetal CPR Calculator: Core Functions and Principles

Worried about the risk of fetal intrauterine hypoxia? This tool provides a quick assessment by calculating the fetal cerebroplacental ratio (CPR). CPR is the ratio of the middle cerebral artery pulsatility index (MCA PI) to the umbilical artery pulsatility index (UA PI) (CPR = MCA PI / UA PI). A decreased CPR value indicates that the fetus may have initiated a brain-sparing mechanism, signaling a potential risk of intrauterine hypoxia.

Why Choose Our Fetal CPR Calculator?

• Accurate dual-parameter calculation: Enter both MCA PI and UA PI values to automatically calculate the CPR ratio.
• Instant status assessment: Automatically determines "Normal" or "Warning: Intrauterine Hypoxia" status based on clinical thresholds.
• Zero learning curve: No medical background required. Simply enter the values to get a professional-grade assessment reference.

How to Use

1. Enter the middle cerebral artery pulsatility index in the "MCA PI" box (e.g., 1.8).
2. Enter the umbilical artery pulsatility index in the "UA PI" box (e.g., 1.0).
3. Click the "Calculate" button to get the CPR value and fetal status assessment.

Frequently Asked Questions (FAQ)

• At what CPR value should I be concerned?
  Generally, a CPR < 1.08 indicates an increased risk, but the specific threshold must be evaluated in conjunction with gestational age and clinical judgment.
• Do the input values require specific units?
  This tool requires pure numbers without units. Ensure you are using PI values from standard ultrasound examinations.

Disclaimer

The calculation results are for reference only and cannot replace professional medical diagnosis. Input values must come from standard ultrasound tests. Always consult an obstetrician for abnormal results. This tool does not store any medical data and processes only one set of parameters at a time.

Technical Notes & Recommendations

It is recommended that high-risk pregnant women monitor their CPR monthly after 28 weeks of gestation. For example: If MCA PI = 1.5 and UA PI = 1.3, the CPR = 1.15 (Normal). If the UA PI rises to 1.7, the CPR = 0.88 (Abnormal). Note that CPR should be evaluated comprehensively alongside fetal heart rate monitoring and ultrasound scans to avoid isolated interpretation.