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The predictive ability of conditional fetal growth percentiles
Jennifer A Hutcheon1, Grace M Egeland, Lucie Morin
1Department of Epidemiology & Biostatistics, McGill University, Montreal, Quebec, Canada.
Paediatric and Perinatal Epidemiology
|April 27, 2010
Summary
Conditional fetal growth percentiles, which account for earlier pregnancy weight, do not better predict adverse perinatal outcomes than conventional charts. Further research is needed to understand why this growth measure is not superior for identifying fetal growth restriction.
Area of Science:
- Perinatal Medicine
- Fetal Development
- Biostatistics
Background:
- Conditional fetal growth percentiles offer a statistically refined approach to measuring fetal growth.
- Their clinical utility in predicting adverse perinatal outcomes, particularly fetal growth restriction, remains unverified.
Purpose of the Study:
- To evaluate if conditional fetal growth percentiles improve the identification of adverse perinatal outcomes compared to conventional methods.
- To assess the predictive accuracy of conditional percentiles for fetal growth restriction.
Main Methods:
- Utilized a large clinical ultrasound database from the Royal Victoria Hospital, Montreal.
- Calculated conditional fetal growth percentiles based on birth weight and 32- or 33-week ultrasound weight.
- Compared the risk of adverse perinatal outcomes in small-for-gestational-age infants identified by conditional versus conventional percentiles.
Main Results:
- Conditional percentiles did not enhance the identification of adverse perinatal outcomes across various small-for-gestational-age thresholds (5th-20th).
- No significant improvement was observed when compared to conventional weight-for-gestational-age charts in predicting adverse outcomes.
- The study found conditional percentiles were not superior to traditional methods for identifying fetal growth restriction.
Conclusions:
- Conditional fetal growth percentiles, despite statistical advantages, did not demonstrate improved prediction of adverse perinatal outcomes in this cohort.
- Current evidence suggests conditional percentiles do not outperform conventional charts for identifying fetal growth restriction.
- Further investigation is required to validate these findings and explore the reasons behind the lack of benefit.
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