Extreme Premature Small for Gestational Age Infants Have Appropriate Catch-up Growth at Term Equivalence Compared with Extreme Premature Appropriate for Gestational Age Infants

Identification of Growth Patterns in Low Birth Weight Infants from Birth to 5 Years of Age: Nationwide Korean Cohort Study

This study aimed to investigate the nationwide growth pattern of infants in Korea according to the birth-weight group and to analyze the effect of growth on development. A total of 430,541 infants, born in 2013 and who received the infant health check-up regularly from 6 months to 60 months of age, were included. The weight, height, head circumferences percentiles, and neurodevelopment using screening tests results were compared among the birth-weight groups. Using longitudinal analysis, the study found a significant difference in height, weight, and head circumference, respectively, according to age at health check-up, birth weight group, and combination of age and birth weight (p < 0.001). The growth parameters at 60 months of age showed a significant correlation with those at 6 months of age especially in extremely low birth weight infants. The incidence of suspected developmental delay was significantly higher in infants with growth below the 10th percentiles than in those with growth above the 10th percentiles. Among 4571 (1.6%) infants with suspected developmental delay results at 60 months of age, birth weight, sex, and poor growth parameters were confirmed as associated factors. This nationwide Korean study shows that poor growth and neurodevelopment outcomes persisted among low-birth-weight infants at 60 months of age. Our findings provide guidance for developing a nationwide follow-up program for infants with perinatal risk factors in Korea.

WHO Child Growth Standards in context: The Baby-bod Project - Observational study in Tasmania

OBJECTIVE

This research evaluated (1) differences in body size and composition of Tasmanian infants at birth and 3 and 6 months postpartum compared with WHO child growth standards and (2) body composition changes in Tasmanian infants at the extremes of the weight-for-length (WFL) spectrum.

DESIGN

Observational study.

SETTING

A hospital in Northern Tasmania, Australia.

PATIENTS

315 healthy infants (~90% Caucasian) born between 2017 and 2019 in Tasmania.

INTERVENTIONS

Body composition and anthropometric measures at 0, 3 and 6 months.

MAIN OUTCOME MEASURES

Growth characteristics at birth and growth trajectories from 0 to 6 months were compared against WHO child growth standards for 0-2 years.

RESULTS

Overall, growth of Tasmanian infants in the first 6 months of life was similar to the global prescriptive standards. Trajectories of fat mass (FM) and fat-free mass (FFM) accrual in infants from the extremes of the size spectrum appear to converge at the 6-month time point. Infants in the lower extremity demonstrated the most precipitous accrual in percentage FM (and the steepest decline in percentage FFM), compared with all other infants.

CONCLUSION

No significant deviations of growth were observed in Tasmanian infants from 0 to 6 months in comparison to the WHO prescriptive growth standards. Infants below the third percentile WFL showed the most precipitous increase in FM accretion. Periodic comparisons local infants with global standards will enable identification of significant deviations from optimal growth patterns.

Growth patterns over 2 years after birth according to birth weight and length percentiles in children born preterm

PURPOSE

To analyze growth patterns over 2 years after birth according to preterm infant birth weight and length percentiles.

METHODS

Anthropometric measurements of 82 preterm infants were retrospectively reviewed. Preterm infants with birth weight or length below the 10th percentile were classified as small for gestational age (SGA) (n=19) and those between the 10th and 89th percentile as appropriate for gestational age (AGA) (n=63). The association between the length standard deviation score (SDS) at 2 years of corrected age and clinical factors were analyzed.

RESULTS

The length SDS of the SGA group was significantly increased at 6 months (-1.30±1.71) and 24 months (-0.97±1.06) of corrected age. The length SDS was lower in the SGA group than those in the AGA group at 6 months (-1.30±1.71 vs. -0.25±1.15, P=0.004), 18 months (-0.97±1.39 vs. -0.03±1.29, P=0.015), and 24 months (-0.97±1.06 vs. -0.29±1.12, P=0.022,). The percentage of children with a length SDS of <-2 (growth failure) at 24 months was 15.8% in the SGA group and 4.8% in the AGA group (P=0.108). Multiple linear regression analysis demonstrated that length at 24 months of corrected age was negatively correlated with birth length below the 10th percentile (coefficient β=-0.91, P=0.001) and duration of stay in the neonatal intensive care unit (NICU) (coefficient β=-0.01, P=0.001).

CONCLUSION

Despite the fact that catch-up growth occurs during the early period of infancy in a large portion of preterm SGA infants, a significant portion of these infants show growth failure at 24 months of age. Growth over 2 years after birth is affected by birth length and duration of stay in the NICU in preterm children.

Physical Activity and Spatial Memory Are Minimally Affected by Moderate Growth Restriction in Preterm Piglets

BACKGROUND

Preterm birth is associated with impaired brain functions, but it is unknown whether fetal growth restriction (GR) makes these deficits worse. Using piglets as a model for preterm infants, we hypothesized that moderate GR reduces growth rate, physical activity, and spatial memory in the first weeks after preterm birth.

METHODS

Preterm pigs were delivered by caesarean section and fed until 19 days (n = 830 from 55 pregnant sows) and received intensive clinical care. GR pigs were classified as animals with the lowest 5-20% percentile birth weight within each litter and were compared with litter-mate controls (21-100% percentile birth weight). Basic motor skill development, physical activity, and morbidities (e.g., necrotizing enterocolitis) were recorded within the first week. Weight of internal organs and data from a T-maze spatial memory test were noted until 19 days.

RESULTS

Moderate GR and control preterm pigs (birth weights 728 ± 140 and 1,019 ± 204 g, respectively) showed similar relative weights of internal organs (relative to body), except higher adrenal gland weights in GR pigs (+20-50%, p < 0.05). This was associated with a tendency to higher plasma cortisol (p < 0.05 on day 11). GR preterm pigs showed delayed ability to stand and walk (days 2-5, p < 0.01), but physical activity and proportion of correct choices in a T-maze test (70.3 vs. 71.6%) were similar.

CONCLUSION

Moderate GR has limited effect on motor function and spatial memory in the early postnatal period of preterm pigs, despite some initial delays in basic motor skills. In the postnatal period, moderately growth-restricted preterm infants may adapt well with regards to organ growth and neurodevelopment.