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Related Experiment Video

Updated: May 15, 2026

Scanning Skeletal Remains for Bone Mineral Density in Forensic Contexts

Scanning Skeletal Remains for Bone Mineral Density in Forensic Contexts

Published on: January 29, 2018

Differences in birth weight by sex using adjusted quantile distance functions.

Anne-Catherine Lehre¹, Petter Laake, Joseph Andrew Sexton

¹Department of Biostatistics, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.

Statistics in Medicine

|January 23, 2013

Summary

Boys exhibit greater birth weight variability than girls, a difference sustained even after adjusting for factors like maternal age and smoking. Gestational age and preeclampsia uniquely impacted each sex differently.

Keywords:

adjusted quantile distance function birth weight sex differences

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Anogenital Distance and Perineal Measurements of the Pelvic Organ Prolapse (POP) Quantification System

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Published on: September 20, 2018

Area of Science:

Obstetrics and Gynecology
Pediatrics
Biostatistics

Background:

Birth weight is a critical indicator of neonatal health and development.
Understanding sex-based differences in birth weight distribution is crucial for targeted perinatal care.
Previous studies suggest potential sex disparities in birth weight, but variability analysis requires further investigation.

Purpose of the Study:

To analyze and compare birth weight distribution variability between male and female newborns.
To investigate how covariates such as maternal age, gestational age, preeclampsia, maternal diabetes type 1, maternal smoking status, and parity influence sex differences in birth weight.

Main Methods:

Utilized the quantile distance function to quantify differences between birth weight distribution functions for boys and girls.
Employed an adjusted quantile function to assess the impact of covariates on sex-specific birth weight variability.
Analyzed data from newborns born in Norway in 2008.

Main Results:

At term (gestation >= 37 weeks), boys demonstrated significantly greater birth weight variability compared to girls.
These sex differences in birth weight variability persisted after adjusting for multiple covariates.
Maternal age and smoking influenced both sexes equally, while gestational age, preeclampsia, maternal diabetes type 1, and parity showed sex-specific effects.

Conclusions:

The quantile distance function is an effective tool for analyzing sex differences in birth weight and the influence of covariates.
Boys exhibit inherently greater variability in birth weight than girls, independent of several key perinatal factors.
Specific maternal and gestational factors differentially impact birth weight in boys and girls, highlighting the need for sex-aware perinatal health strategies.