Associations between size at birth and size at 6 years among preterm infants: a retrospective cohort study

Pediatr Int. 2022 Jan;64(1):e14844. doi: 10.1111/ped.14844.

Abstract

Background: Little is known about the relationship between fetal growth and size at school age in children born prematurely. We evaluated the relationships between gestational age and anthropometric z-scores at birth and size at 6 years of age in very-low-birthweight infants born at <30 weeks' gestation.

Methods: We collected data from the medical records of 187 preterm children at birth and 6 years of age. We evaluated correlations between gestational age and z-scores for weight, body length, and head circumference at birth and z-scores for weight, height, and body mass index at 6 years of age.

Results: Simple regression analysis showed that, in boys and the overall group, gestational age and z-scores for weight, body length, and head circumference at birth had significant association with z-scores for weight, height, and body mass index at 6 years of age. No significant associations were found in girls, except for weight z-scores at 6 years with gestational age and head circumference z-scores at birth. Multiple regression analysis showed that gestational age and length z-score at birth were significantly and independently associated with weight and height z-score at 6 years. Gestational age was also significantly and independently associated with body mass index z-score at 6 years.

Conclusion: Gestational age and fetal growth in length (assessed with the birth-length z-score) were associated with anthropometric z-scores at 6 years in very-low-birthweight children born at <30 weeks of gestation, especially in boys.

Keywords: anthropometry; body mass index; fetal growth restriction; very-low-birth-weight infant; z-score.

MeSH terms

  • Birth Weight
  • Body Mass Index
  • Child
  • Female
  • Gestational Age
  • Humans
  • Infant
  • Infant, Newborn
  • Infant, Premature*
  • Infant, Small for Gestational Age
  • Infant, Very Low Birth Weight*
  • Male
  • Retrospective Studies