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Updated: Oct 3, 2025
14:19
Fetal Echocardiography and Pulsed-wave Doppler Ultrasound in a Rabbit Model of Intrauterine Growth Restriction
Published on: June 29, 2013
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Variation in Fetal Weight Percentile Estimates.
Garvit D Khatri1, Michael L Richardson1, Manjiri Dighe1
1University of Washington, Seattle, Washington, USA.
Summary
Estimated fetal weight percentiles are imprecise predictors of actual fetal growth. Reporting expected variations can prevent misdiagnosis of fetal growth restriction (IUGR) and macrosomia, reducing unnecessary interventions.
Area of Science:
- Obstetrics and Gynecology
- Fetal Medicine
- Medical Imaging
Background:
- Fetal weight percentiles are commonly used in clinical practice.
- Current reporting methods often lack error margins, potentially leading to misclassification.
Purpose of the Study:
- To compare estimated fetal weight percentiles with actual observed percentiles.
- To assess the accuracy of estimated fetal weight percentiles in a large cohort.
Main Methods:
- Retrospective search of obstetrical ultrasound reports (July 2014 - July 2020).
- Data extraction included demographic information, fetal weight, and weight percentiles.
- Quantile-quantile plots were generated for analysis.
Main Results:
- The study analyzed 6259 ultrasounds from 4060 patients.
- While median values approximated the line of identity, considerable variation was observed.
- Estimated fetal weight percentiles were found to be rough predictors of actual percentiles.
Conclusions:
- Estimated fetal weight percentiles demonstrate significant variability and are imprecise.
- Reporting estimated variations alongside percentiles is recommended.
- Accurate percentile reporting can prevent misdiagnosis of fetal growth abnormalities and reduce clinical complications.
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