Preterm appropriate for gestational age infants: size at birth explains subsequent growth

Growth patterns by birth size of preterm children born at 24-29 gestational weeks for the first 3 years

BACKGROUND

Concerns are prevalent about preterm infant long-term growth regarding plotting low on growth charts at discharge, stunting, underweight, high body fat and subsequent cardiometabolic morbidities.

OBJECTIVES

To examine (a) longitudinal growth patterns of extremely and very preterm infants to 3 years corrected age (CA) (outcome), categorised by their birthweight for gestational age: small, appropriate and large for gestational age (SGA, AGA and LGA, respectively) (exposure); and (b) the ability of growth faltering (<-2 z-scores) to predict suboptimal cognitive scores at 3 years CA.

METHODS

Post-discharge head, length, weight and weight-4-length growth patterns of the PreM Growth cohort study infants born <30 weeks and < 1500 g, who had dietitian and multi-disciplinary support before and after discharge, were plotted against the World Health Organization growth standard. Infants with brain injuries, necrotising enterocolitis and bronchopulmonary dysplasia were excluded.

RESULTS

Of the included 405 infants, the proportions of infants with anthropometric measures > - 2 z-scores improved with age. The highest proportions <-2 z-scores for length (24.2%) and weight (24.0%) were at 36 gestational weeks. The proportion with small heads was low by 0 months CA (1.8%). By 3 years CA, only a few children plotted lower than -2 z-scores for length, weight-4-length and weight (<6%). After zero months CA, high weight-4-length and body mass index > + 2 z-scores were rare (2.1% at 3 years CA). Those born SGA had higher proportions with shorter heights (16.7% vs. 5.2%) and lower weights (27.8% vs. 3.5%) at 3 years CA compared to those born AGA. The ability of growth faltering to predict cognitive scores was limited (AUROC 0.42, 95% CI 0.39, 0.45 to 0.52, 95% CI 0.41, 0.63).

CONCLUSIONS

Although children born <30 weeks gestation without major neonatal morbidities plot low on growth charts at 36 weeks CA most catch up to growth chart curves by 3 years CA.

Preterm pigs for preterm birth research: reasonably feasible

Preterm birth will disrupt the pattern and course of organ development, which may result in morbidity and mortality of newborn infants. Large animal models are crucial resources for developing novel, credible, and effective treatments for preterm infants. This review summarizes the classification, definition, and prevalence of preterm birth, and analyzes the relationship between the predicted animal days and one human year in the most widely used animal models (mice, rats, rabbits, sheep, and pigs) for preterm birth studies. After that, the physiological characteristics of preterm pig models at different gestational ages are described in more detail, including birth weight, body temperature, brain development, cardiovascular system development, respiratory, digestive, and immune system development, kidney development, and blood constituents. Studies on postnatal development and adaptation of preterm pig models of different gestational ages will help to determine the physiological basis for survival and development of very preterm, middle preterm, and late preterm newborns, and will also aid in the study and accurate optimization of feeding conditions, diet- or drug-related interventions for preterm neonates. Finally, this review summarizes several accepted pediatric applications of preterm pig models in nutritional fortification, necrotizing enterocolitis, neonatal encephalopathy and hypothermia intervention, mechanical ventilation, and oxygen therapy for preterm infants.

Influence of H-HOPE intervention for premature infants on growth, feeding progression and length of stay during initial hospitalization

OBJECTIVE

To examine whether premature infants receiving the maternally administered H-HOPE (Hospital to Home Transition-Optimizing Premature Infant's Environment) intervention had more rapid weight gain and growth, improved feeding progression and reduced length of hospital stay, compared with controls.

STUDY DESIGN

Premature infants born at 29-34 weeks gestational age and their mothers with at least two social-environmental risk factors were randomly assigned to H-HOPE intervention (n=88) or an attention control (n=94) groups. H-HOPE consists of a 15-min multisensory intervention (Auditory, Tactile, Visual and Vestibular stimuli) performed twice daily prior to feeding plus maternal participatory guidance on preterm infant behavioral cues.

RESULT

H-HOPE group infants gained weight more rapidly over time than infants in the control group and grew in length more rapidly than control infants, especially during the latter part of the hospital stay.

CONCLUSION

For healthy preterm infants, the H-HOPE intervention appears to improve weight gain and length over time from birth to hospital discharge.

Improvement in long-term breastfeeding for very preterm infants

INTRODUCTION

The extensive health benefits of breastfeeding preterm infants for both mother and infant have been widely reported. However, establishing and maintaining breastfeeding for very preterm (VP) infants remain challenging. The aim of this study was to examine changes in breastfeeding of VP infants over time.

SUBJECTS AND METHODS

Breastfeeding questionnaires were administered to two cohorts of parents of VP infants (<32 weeks) cared for at the tertiary perinatal or surgical neonatal unit in Western Australia. Of these, 488 infants were included in cohort 1 (C1) (births from January 1, 1990 to June 30, 1992) and 253 in cohort 2 (C2) (from January 1, 2011 to September 14, 2012).

RESULTS

More mothers (96.8%) initiated breastfeeding in C2 compared with those in C1 (65.6%) (p<0.001). Additionally, 41.4% of mothers in C2 breastfed for more than 6 months, relative to 25.8% in C1 (p<0.001). The benefits of breastfeeding were endorsed by more women in C2 (45.8%) compared with C1 (11.4%) (p<0.01). Reasons for stopping feeding remained largely consistent.

CONCLUSIONS

Significant improvements were evident in the initiation and duration of breastfeeding of the VP infant over time. This improvement was associated with attitudinal shifts in mothers about the benefits of breastfeeding.

[Growth of preterm-born children]

Children born prematurely might experience a period of growth restriction just after birth. Catch-up growth begins during the first months of life and can be slow and progressive. These children may remain shorter and thinner throughout infancy and childhood compared to children born at term. In some cases, complete catch-up growth occurs only during adolescence. However, some children do not completely recover growth, and adults born prematurely are at increased risk of short stature. Impaired growth is more frequent in those born preterm and small for gestational age. Factors such as target height, birth weight, gestational age, neonatal morbidities and maternal education interfere in growth potential. Special attention should be given to children born preterm during the whole growth period.

Head circumference catch-up growth among preterm very low birth weight infants: effect on neurodevelopmental outcome

AIMS

The purpose of this study was to determine whether head circumference (HC) catch-up is associated with improved neurocognitive development.

DESIGN

A retrospective cohort study was conducted in 179 preterm very low birth weight (VLBW) (BW≤1500 g) infants. The infants were born in 2000-2002 and were followed to the age of 5.5 years. The association between HC catch-up and neurodevelopmental outcome was assessed and perinatal risk factors, infant characteristics and nutritional practices associated with HC catch-up were determined.

RESULTS

HC catch-up occurred in 59 (34%) infants and was positively correlated with neurodevelopmental outcome. The likelihood of HC catch-up increased with increasing birth weight and gestational age. HC catch-up occurred more often with breast milk feeding during hospitalization and with supplemental formula feeding at discharge, but decreased in prevalence with longer duration of breastfeeding after discharge. HC catch-up was more likely to occur in first-born infants and in families with high socioeconomic status. Most HC catch-up occurred between birth and three months corrected age.

CONCLUSION

Among preterm-VLBW infants, there is a close relation between HC growth and neurodevelopmental outcome. Efforts to improve neurocognitive outcomes should focus on factors associated with HC catch-up.

Results of extremely-low-birth-weight infants randomized to receive extra enteral calcium supply

BACKGROUND AND OBJECTIVE

Bone mineral deficiency continues to occur in extremely-low-birth-weight (ELBW) infants despite formulas enriched in calcium (Ca) and phosphorus (P). This study tested whether extra enteral Ca supplementation increases bone mineral content (BMC) and prevents dolichocephalic head flattening and myopia in ELBW infants.

STUDY DESIGN

Infants 401 to 1000 birth weight receiving enteral feeds were randomized to receive feeds supplemented with Ca-gluconate powder or pure standard feeds. The main outcome measures were the excretion of Ca and P by weekly spot urine measurements, the degree of dolichocephalic deformation (fronto-occipital diameter to biparietal diameter ratio, FOD/BPD) at 36 weeks postmenstrual age, and the BMC (by dual-energy x-ray absorptiometry) at discharge. Cycloplegic refraction was measured at 18 to 22 months corrected age.

PATIENTS AND RESULTS

Ninety-nine ELBW infants with a gestational age of 26 weeks (23-31) (median [minimum-maximum]) were randomized at a postnatal age of 12 days (5-23) weighing 790 g (440-1700). Urinary Ca excretion increased and P excretion decreased in the Ca-supplemented group. Total BMC was 89.9 ± 2.4 g (mean ± SE) in the supplemented group and 85.2 ± 2.6 g in the control group (P = 0.19). The FOD/BPD was 1.50 (1.13-1.69, mean ± SD [standard deviation]) and 1.47 (1.18-1.64) in the supplemented and control groups, and the refraction 0.98  ± 1.23 and 1.40 ± 1.33 dpt (P = 0.68), respectively in 64 ELBW infants (79% of survivors) at 2-year follow-up.

CONCLUSIONS

Extra enteral Ca supplementation did not change BMC, head shape, or refraction. The decreased P excretion may reflect P deficiency in infants receiving extra Ca, preventing improved bone mineral accretion.