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Customised birthweight percentiles: does adjusting for maternal characteristics matter?
J A Hutcheon1, X Zhang, S Cnattingius
1Department of Epidemiology and Biostatistics, McGill University, Montréal, Quebec, Canada. jennifer.hutcheon@mail.mcgill.ca
BJOG : an International Journal of Obstetrics and Gynaecology
|October 1, 2008
Summary
A non-customised intrauterine-based standard effectively predicts perinatal mortality risk, similar to customised standards. Customising standards for maternal factors offers minimal improvement in predicting stillbirth and early neonatal mortality.
Area of Science:
- Perinatal health research
- Obstetrics and Gynecology
- Public Health Epidemiology
Background:
- Accurate prediction of perinatal mortality risk is crucial for effective interventions.
- Customised birthweight standards improve risk prediction but are complex to implement.
- Evaluating simpler, non-customised standards is essential for widespread clinical application.
Purpose of the Study:
- To assess if a non-customised, intrauterine-based standard can predict perinatal mortality risk as effectively as a customised standard.
- To compare the predictive performance of different small-for-gestational-age (SGA) classification methods for stillbirth and early neonatal mortality.
Main Methods:
- Population-based cohort study in Sweden (1992-2001) including 782,303 births.
- Calculated relative risks (RRs) for stillbirth and early neonatal mortality using three SGA standards: customised, population birthweight, and intrauterine-based.
- Data included birthweight, gestational age, and maternal characteristics.
Main Results:
- The intrauterine-based standard showed similar risk prediction for stillbirth and early neonatal mortality compared to the customised standard.
- Both intrauterine-based and customised standards identified higher risks for SGA births than the simple birthweight standard.
- Customising standards for maternal characteristics did not significantly enhance perinatal mortality prediction.
Conclusions:
- A non-customised intrauterine-based standard is a viable alternative to customised standards for predicting perinatal mortality risk.
- The predictive value for stillbirth and early neonatal mortality is comparable between customised and non-customised intrauterine-based standards.
- Routine customisation of population standards for maternal factors offers limited additional benefit in predicting perinatal mortality.
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