Sexual differences in anthropometric measurements in French newborns

Area of Science:

• Pediatrics
• Human Biology
• Neonatology

Background:

• Anthropometric measurements in newborns are crucial for assessing growth and development.
• Understanding sexual dimorphism in infant measurements can provide insights into sex-specific health outcomes.
• Previous studies have indicated potential sex differences in neonatal anthropometry.

Purpose of the Study:

• To investigate sexual differences in anthropometric measurements of preterm and full-term infants.
• To analyze variations in body weight, length, circumferences, and skinfold thicknesses between male and female neonates.
• To explore the relationship between these anthropometric differences and potential sex-based advantages in neonatal outcomes.

Main Methods:

• A retrospective analysis of 17,787 infants born between 1980 and 1990 at Clamart Hospital.
• Measurement of key anthropometric parameters including body weight, body length, head circumference, chest circumference, subscapular skinfold, and tricipital skinfold.
• Calculation of weight-for-height indices such as Body Mass Index (BMI) and Ponderal Index (PI).

Main Results:

• Male newborns exhibited significantly larger body weight, body length, head circumference, and chest circumference.
• Female newborns showed significantly higher subscapular and tricipital skinfold thicknesses, indicating greater fatness.
• While males had higher BMI and weight/length index, the ponderal index revealed no significant sexual difference.

Conclusions:

• Significant sexual dimorphism exists in neonatal anthropometry, with males generally larger in size and females exhibiting greater fat deposition.
• The observed differences in fatness in females may be linked to better neonatal outcomes, although weight-for-height indices did not consistently support a female advantage.
• These findings highlight the importance of considering sex-specific reference standards for infant anthropometric assessment.