The premature small-for-gestational-age infant during the first year of life: comparison by birth weight and gestational age

To determine the effect of intrauterine growth retardation on the outcome of the premature infant, we compared a group of 35 premature, small-for-gestational-age (SGA) infants with two groups of premature, appropriate-for-gestational-age (AGA) infants: one with similar birth weight (AGA-BW group) and the other with similar gestational age (AGA-GA group). Groups were matched by year of birth, race, gender, and socioeconomic status. Infants were free of major congenital anomalies and intrauterine infection. They were evaluated at term, at 20 and 40 weeks, and at 1 year corrected age. The SGA infants had a lower mean developmental quotient than the two groups of AGA infants. The SGA infants had significantly smaller body dimensions at birth, more nursery complications, and a higher incidence of major neurologic problems than their AGA-GA matches but were comparable to the AGA-BW matches. Poor growth constitutes an additional risk factor to prematurity. The results highlight the importance of comparing premature SGA infants with premature AGA infants of similar gestational age rather than similar birth weight.     

Catch-up growth in very-low-birth-weight infants. Clinical correlates

Clinical correlates of catch-up growth were documented in 182 very-low-birth-weight (VLBW) infants (less than 1.5 kg) followed up prospectively until a corrected age of 33 months. At birth, 147 infants had weights appropriate for gestational age (AGA), and 35 were small for gestational age (SGA). The infants in each group were categorized as small if body weight was 2 SDs below the mean for age or appropriate if body weight was within 2 SDs of the mean at birth and at corrected ages of 40 weeks and 8, 21, and 33 months. Of the 147 AGA infants, 67 (46%) weighed less than 2 SDs of the mean for age at a corrected age of 40 weeks, 40 (27%) at 8 months, 28 (19%) at 21 months, and 25 (17%) at 33 months. Of the 35 SGA infants, 32 (91%) had subnormal weight at 40 weeks, 17 (49%) at 8 months and 21 months, and 16 (46%) at 33 months. Significant correlates of poor catch-up growth in the AGA group were birth weight, gestational age, severity of neonatal complications, poor neonatal head growth, and chronic physical and neurologic sequelae. In the infants in the SGA group, the correlates of poor catch-up growth were birth weight, multiple birth, and social class.     

The relationship between intrauterine and postnatal growth on the subsequent psychomotor development of very low birthweight (VLBW) infants

ABSTRACT. The aim of this study was to demonstrate the relationship between intrauterine and postnatal growth and subsequent neurological and intellectual development of very low birth weight (VLBW) infants. The effect of intrauterine growth was assessed by comparing the developmental outcomes of the 131 appropriate weight for gestational age (AGA) infants with the 33 small for gestational age (SGA) infants. No significant differences were found between the two groups with respect to head circumference, neurological, intellectual or sensory handicap rates. The mean General Quotient (GQ) at the last clinic assessment for the AGA infants was 101.2 and 97.2 for the SGA infants. The effect of extra-uterine growth on subsequent development was assessed in the AGA and SGA infants separately, at the time of discharge and again at 12 months. The 31 AGA infants who failed to grow adequately in the nursery had more neonatal risk factors than the 100 AGA infants who continued to grow adequately after birth. This early postnatal growth failure was not predictive of developmental outcome. At 12 months of age, 26 infants (20%) who were initially appropriately grown at birth were failing to thrive. These infants had sustained more chronic diseases and caretaking disorders in the first year of life than their appropriately grown counterparts. They also had lower GQ and head circumference measurements (p<.05). The SGA infants who exhibited “catch up'’growth between birth and term had larger head circumference measurements at 1 year than those with persistent growth failure. Growth assessment at 12 months of age was not predictive of developmental outcome in SGA infants. We failed to show a relationship between intrauterine growth of VLBW infants and their subsequent development. AGA infants whose weights had dropped to the 3rd percentile by 12 months of age had a poorer outcome than their appropriately grown counterparts. Furthermore, early postnatal growth failure before term had no additional effects if catch up growth occurred thereafter. In the SGA group neither failure to reach the 3rd percentile by term or 12 months affected outcome.     

Differential effects of intrauterine and postnatal brain growth failure in infants of very low birth weight

We investigated the contribution of brain growth failure to outcome in infants of very low birth weight (VLBW; less than 1.5 kg) who were appropriate for gestational age (AGA; n = 379) or small for gestational age (SGA; n = 102). Growth was assessed at birth, term, and 8 and 20 months' corrected age and results of a Bayley Mental Developmental Index (MDI) and neurologic examination were evaluated at 20 months of age. Both groups had similar 20-month MDI scores (93 vs 90) and similar rates of neurologic impairment (14% vs 10%). More SGA infants (25%) than AGA infants (14%) had a subnormal head circumference at 8 months' corrected age, indicating failure to catch up in head growth. Subnormal head size at 8 months predicted the 20-month MDI score for both groups. However, multivariate analysis indicated that, whereas subnormal 8-month head size was directly associated with the MDI score in AGA children, in SGA children 8-month head size was not significantly related to the MDI score when neonatal illness, neurologic impairment, socioeconomic status, and race were controlled for. We conclude that in AGA VLBW infants, subnormal head size at 8 months results from major neonatal illness and has adverse later effects. In SGA infants, subnormal head size at 8 months has many causes, including growth retardation in utero, which may not have an adverse effect on outcome; if subnormal head size is superimposed with neonatal illness, a poorer outcome is likely.     

Catch-up growth of head circumference of very low birth weight,small for gestational age preterm infants and mental development to adulthood

OBJECTIVE: To examine the influence of postnatal energy quotient (EQ, energy intake/kg body weight per day) on head circumference (HC) growth and mental development of very low birth weight (VLBW), small for gestational age (SGA, <10th percentile) preterm infants. STUDY DESIGN: SGA VLBW preterm infants (n = 46) with primarily symmetric intrauterine growth restriction were compared with 62 appropriate for gestational age (AGA) VLBW preterm infants and 73 term infants from the Bonn Longitudinal study. RESULTS: Twenty-seven of 46 (59%) of the SGA preterm infants showed complete HC catch-up growth by the age of 12 months, but mostly before 6 months after term (HC catch-up group). These infants had significantly higher mean EQs from day 2 to 10 than the group of 19 infants without HC catch-up (EQ, 95 vs 78). Mean EQs correlated significantly with developmental and intelligence quotients (DQ/IQ) from 18 months to 6 years. As adults, the HC of the HC catch-up group was not significantly different from that of the AGA preterm infants, the term infants, and their parents. The group without HC catch-up had smaller HC as adults. CONCLUSIONS: Our data suggest that early postnatal high-energy nutrient intake for SGA preterm infants is needed to promote HC catch-up growth and to prevent negative consequences of undernutrition.     

Growth and development are similar in VLBW children born appropriate and small for gestational age: an interim report on 97 preschool children

AIM: To investigate growth and development in a cohort of children born with very low birth weight (VLBW) treated at a single tertiary neonatal unit. METHODS: We studied 97 children born between January 1995 and July 1997 with BW <1,500 g. At follow-up (mean age 3.7 years) anthropometric data and data on neurological status, motor, speech and language development were collected. Small for gestational age (SGA) was defined as weight and/or length at birth <10th percentile; shortness at follow-up was defined as height <10th percentile. RESULTS: Comparison was made between the appropriate for gestational age (AGA) (n = 46) and SGA (n = 51) groups. At follow-up, 23 AGA and 35 SGA children were short, had a smaller head circumference (-1.9 vs -0.8 SDS), were lighter at birth (BW -1.3 vs -0.7 SDS), and had a higher rate of broncho-pulmonary dysplasia (BPD) (28 vs 12); no differences in neonatal characteristics or neurological status were evident. A higher frequency of motor delay occurred in the 'short' group. Short children also had a smaller head circumference (HC) (-1.6 vs -0.7). Short SGA children had a higher frequency of BPD, smaller HC (-2.1 vs -1.0), and a slightly higher proportion of suspicious neurological findings, motor delay, and speech and language delay (n.s.). CONCLUSIONS: Preterm VLBW infants, whether AGA or SGA at birth, face the risk of being short at preschool age. Height outcome is probably influenced by postnatal factors. Our data also suggest that short stature is associated with developmental difficulties in this population.     

Catch up growth and pancreatic function in growth retarded neonates.

To test the hypothesis that relative pancreatic dysfunction is a determinant of catch up growth in small for gestational age (SGA) babies, 47 such babies (median gestation 38 weeks; range 27-41) and 41 appropriate for gestational age (AGA) babies matched for sex, race, and gestational age were recruited. Anthropometry was performed within 48 hours of birth and at 6 months. Faecal chymotrypsin activities were measured at 0-2 days, 14 days, 6 weeks and 6 months. At 6 months 30 SGA infants and 25 AGA infants were remeasured. In each group, median stool chymotrypsin activities doubled between 0-2 days and 6 months (9.0-25.5 IU/g SGA group; 11.6-25.3 IU/g AGA group). SGA babies had significantly lower chymotrypsin activities at 14 days (10.9 U/g) than AGA babies (15.5 U/g). In the SGA group faecal chymotrypsin activities at 0-2 days were strongly correlated with both catch up weight and with catch up length when corrected for the effects of birthweight. These data show that impaired pancreatic exocrine function at birth is associated with severe intrauterine malnutrition and with impaired catch up growth during the first 6 months of life.     

34 周以下适于胎龄及小于胎龄早产儿出生 2 周内 蛋白质、能量摄入及体质量变化

目的了解34周以下早产适于胎龄儿(AGA)和小于胎龄儿(SGA)生后蛋白质、能量摄入量以及体质量z评分的变化情况。方法回顾收集2012年1月至2014年12月入院的314例早产儿,比较268例AGA和46例SGA早产儿生后2周内蛋白质、能量摄入情况和体质量变化。结果 SGA组住院时间、肠外联合肠内营养时间、全肠内营养时间、达足量喂养时间均较AGA早产儿长,差异有统计学意义(P??0.05);SGA组生后第4、8、12天能量摄入量明显低于AGA组,SGA组生后第6、8天总蛋白质摄入量明显低于AGA组,差异均有统计学意义(P??0.05);SGA组日平均体质量增长量大于AGA组,差异有统计学意义(P??0.05);AGA组与SGA组生后2周内体质量z评分均逐渐远离中位水平,且SGA组2周时体质量z评分低于AGA组(P??0.05)。结论胎龄??34周的SGA早产儿恢复出生体质量后的生长速率快于AGA早产儿,存在一定的追赶生长;但SGA、AGA早产儿的生长均有待提高。     

早产小于胎龄儿生长代谢的临床研究

目的 探讨早产小于胎龄儿（SGA）与适于胎龄儿（AGA）在住院期间生长代谢的差异,为临床对早产SGA进行营养干预提供依据。方法 1 370例早产儿纳入研究,根据胎龄与出生体重的关系分为SGA组（675例）与AGA组（695例）,比较两组早产儿住院期间的一般情况、体格增长及血生化指标等情况。结果 SGA组住院天数长于AGA组（P < 0.05）。与AGA组相比,SGA组出院体重、出院体重Z评分及出院身长均较低,宫外生长迟缓发生率较高（P < 0.05）,头围增长速率大于AGA组。与AGA组相比,SGA组达全肠内喂养时间及需肠外营养时间均较长（P < 0.05）。SGA组入院时白蛋白、前白蛋白、血清磷、出院前总胆汁酸高于AGA组,白蛋白低于AGA组（P < 0.05）。SGA组窒息、新生儿呼吸窘迫综合征、心肌损伤、喂养不耐受、肺炎、败血症、低血糖、低甲状腺素血症的发生率高于AGA组（P < 0.05）。结论 早产SGA住院期间体格发育明显落后于AGA,宫外生长迟缓发生率较高,更易出现并发症。     

晚期早产儿中小于胎龄儿的临床特点

目的探讨晚期早产儿中发生小于胎龄儿(SGA)的围产期因素及新生儿期患病特点。方法对2009年10月至2010年9月在我院新生儿重症监护病房住院、胎龄34～36周的晚期早产儿临床资料进行回顾性分析,比较晚期早产儿中SGA和适于胎龄儿(AGA)的围产期因素及新生儿期患病情况。结果 SGA组(179例)住院天数明显长于AGA组(851例)[(16.4±6.2)天比(11.3±4.1)天,P<0.05]。SGA组母亲妊娠期高血压疾病(HDCP)、多胎妊娠、羊水过少和宫内窘迫的比例均高于AGA组(34.1%比17.9%,29.1%比13.7%,21.2%比12.6%,19.6%11.0%,P均<0.01)。SGA组患儿新生儿窒息、喂养不耐受、颅内出血、低血糖和红细胞增多症的发生率亦明显高于AGA组(12.8%比7.9%,7.8%比3.1%,6.1%比2.6%,27.4%比21.4%,3.4%比0.2%,P均<0.05)。结论母亲HDCP和多胎妊娠是造成晚期早产儿SGA的主要原因,SGA患儿相对于AGA患儿具有更高的患病风险,应针对造成SGA的围产期因素以及新生期疾病特点进行相应预防和干预。     

Metabolic and energy balance in small- and appropriate-for-gestational-age, very low-birth-weight infants

This study compared nutrient utilization and postnatal weight gain composition in eight appropriate for gestational age (AGA: birth weight 1293 ± 107 g; gestational age 28.8 ± 1.4 weeks) and eight symmetrically growth-retarded (SGA: birth weight 1110 ± 230 g; gestational age 32.7 ± 1.9 weeks), very low-birth-weight (VLBW) infants. There was no significant difference in protein, mineral and energy intake between AGA and SGA infants. Nitrogen absorption (84 ± 3 and 83 ± 4%) and nitrogen retention (356 ± 48 and 352 ± 43 mg/kg/day) were similar in both groups. Fat absorption tended to be lower in AGA (78 ± 15%) than in SGA (87 ± 4%) infants. Calcium, phosphorus and magnesium absorptions were similar in AGA and SGA infants. Metabolizable energy utilization was similar in both groups; about 55% was expended and 45% stored in new tissues. Energy expenditure was 58 ± 4 kcal/kg/day in SGA infants and 61 ± 9 kcal/kg/day in AGA infants. Weight gain and its composition were similar in both groups. We conclude that nutrient and energy utilization are similar in AGA and symmetrically growth-retarded, VLBW infants.     

Part 1. Outcome for Small-for-Gestational-Age Infants with Very Low Birth Weight (<1,500g)

Mortality and morbidity of small-for-gestational-age (SGA) infants with very low birth weight (VLBW) (less than 1,500 g at birth) are reported. Survival rate of 47 VLBW infants was 92%, with no statistical difference between SGA and appropriate-for-gestational-age (AGA) groups. Thirty-nine VLBW infants were watched in our follow-up clinic for more than seven months. Overall incidence of major neurologic defects (cerebral palsy, epilepsy or psychomotor retardation) was 12.8%. Handicap was significantly different for SGA and AGA groups, that is, four out of 12 SGA infants (33%), compared with one out of 27 AGA infants (3.3%). Major neurologic defects in VLBW infants were strongly associated with intrauterine growth retardation (IUGR) related to toxemia of pregnancy with onset in the 2nd trimester. Although most of the VLBW SGA infants were IUGR due to noxious intrauterine environments, head sizes of all, with one exception, were growth-restricted in utero. If IUGR, especially retardation of head growth, is detected in utero during the 2nd trimester, discussion between obstetrician and neonatologist about optimal neurological outcome for the infant is mandatory.     

Postnatal growth in VLBW infants: significant association with neurodevelopmental outcome

OBJECTIVE: To study the significance of growth status at birth and postnatal growth on neurodevelopmental outcome in very low birth weight (VLBW) infants. STUDY DESIGN: Growth and neurodevelopment were examined in 219 VLBW (<1250 g) children, 94 small for gestational age (SGA) (<10th percentile) and 125 appropriate for gestational age (AGA) (>10th percentile). Outcome at age 2 was assessed with the Bayley Scales of Infant Development (Mental Developmental Index [MDI], Psychomotor Developmental Index [PDI]) and a standardized neurologic examination. RESULTS: SGA status was not associated with poor neurodevelopmental outcome. However, after adjustment for covariables including cerebral palsy (CP), SGA children with weight <10th percentile at age 2 had lower mean PDI than SGA children with catch-up growth to weight >10th percentile (mean [SD], 89.9 [17.4] versus 101.8 [14.5]; P<.001). AGA children with catch-down growth (weight <10th percentile at age 2) were, independent of CP, more likely to have lower mean MDI (94.9 vs 101.7, P=.05) and PDI (81.9 vs 95.1; P<.001) than AGA children remaining >10th percentile at age 2. They also more frequently had severe CP (22.9% vs 1.2%; P=.008). CONCLUSIONS: In VLBW children, the course of postnatal growth rather than the appropriateness of weight for gestational age at birth determines later neurodevelopmental outcome.     

Increased nucleated red blood cell counts in small for gestational age infants with very low birth weight

We evaluated the nucleated red blood cell (NRBC) counts in all infants with very low birth weight admitted to our neonatal intensive care unit from 1983 to 1986. There were 374 infants with birth weights of 500 g to 1500 g admitted in the first 24 hours after birth, but 31 died before studies were obtained. Of the remainder, 282 were appropriate for gestational age (AGA) and 61 were small for gestational age (SGA). Over 80% of both AGA and SGA infants were inborn and were evaluated within three hours of delivery. Nucleated red blood cell counts were significantly increased in SGA infants compared with AGA infants. The percent of infants with NRBC counts higher than 4.0 and 10.0 x 10(9)/L were 48% and 26%, respectively, in SGA infants compared with 19% and 6%, respectively, in AGA infants. Similarly, the percent of SGA infants with more than 40 or 100 NRBCs per 100 white blood cells were 62% and 36%, respectively, compared with 25% and 6%, respectively, in AGA infants. Data for specific weeks of gestation are provided and the differences were present at each gestational age. Recent data in fetuses with growth retardation, when blood was obtained directly from the fetal umbilical vein, showed an association between elevated NRBC counts and chronic hypoxemia. When increased NRBC counts are seen soon after birth, the possibility of a chronic intrauterine insult should be considered.     

Effect of human milk fortification in appropriate for gestation and small for gestation preterm babies: a randomized controlled trial

OBJECTIVE: To study the effects of human milk fortification on short term growth and biochemical parameters in preterm very low birth weight (VLBW) appropriate for gestation (AGA) and small for gestation (SGA) babies. DESIGN: Prospective, randomized controlled trial. SETTING: Level III neonatal unit. SUBJECTS: Preterm infants weighing < or = 1500 grams and < or = 34 weeks of gestation born between March 2001 to June 2002. METHODS: Babies (n =166) were randomized in two groups either to get fortified human milk or exclusive human milk along with mineral and vitamin supplementation when feed volume reached 150 mL/Kg/day. Fortification was done with a powdered fortifier added in expressed breast milk and continued till the baby reached 2 Kg or full breast feeds. Primary outcome measures were Short-term growth (daily weight, length and head circumference (HC) weekly) till discharge or 2 Kg. RESULTS: Fortification (n = 85, birth weight 1202 g, gestation 30.8 wk) resulted in better growth in preterm VLBW babies as compared to control group (n=81, birth weight 1259 g, gestation 31.3 wk). Weight gain (15.1 and 12.9 g/kg/d, P <0.001), length (1.04 and 0.86 cm/week, P = 0.017) and HC (0.83 and 0.75 cm/week, P<0.001) increased significantly in fortified group. SGA babies showed significant improvements in weight (16 g/Kg/d and 12.9 g/kg/d, P = 0.002) and length (1.09 cm/week and 0.92 cm/week, P = 0.042) in fortified group (n = 38) as compared to control group (n = 29). In AGA subgroup, there was significant increase (P = 0.006) in length (1 cm vs 0.82 cm) in fortified group but no difference in weight (P = 0.12) or HC (P=0.054) in fortified (n=47) vs control (n=52) group. Biochemical parameters were comparable, however feed intolerance was more in control group. CONCLUSION: Preterm VLBW babies showed better growth with human milk fortification. The effect is significant in SGA (weight and length)rather than AGA (only length) babies.     

Growth of 519 Small for Gestational Age Infants during the First Two Years of Life

ABSTRACT. The physical growth of 519 small for gestational age infants (SGA), with a birth weight below the 10th percentile on our own growth curve, born in the region of University Central Hospital of Turku during the period June 1,1981-May 31, 1982, was studied. The study population consists of 4 517 term, appropriate for gestational age (AGA) infants, 488 term SGA infants, 320 preterm AGA infants and 31 preterm SGA infants. The degree of intrauterine growth retardation (IUGR) seemed to have an effect on physical growth in term SGA infants. Those term SGA infants with a low Ponderal Index (PI) (type II) were taller and had a larger head circumference at the age of 24 months than term SGA infants with adequate PI (type I). Among the preterm SGA infants the degree of IUGR seemed to have no effect on later growth. Smoking is still one of the main risk factors associated with poor intrauterine growth. In this study we also found that smoking has an effect on later growth; the children of smoking mothers were smaller than those of non-smoking mothers in the AGA group. Among the SGA infants the infants of non-smoking mothers were bigger than those of smoking mothers. This difference could be explained by other factors associated with SGA. We found that in spite of the catch-up growth during the first months, 26% of the severely SGA infants (birth weight below the 2.5th percentile) still had a weight below the 2.5th percentile at the age of 24 months.     

61例极低出生体重早产儿生后第一年生长发育的随访

目的 探讨极低出生体重早产儿生后第一年生长发育情况及相关影响因素。方法 对61例极低出生体重早产儿进行出生后第一年的生长发育监测。采用Z评分法评价体格指标、丹佛发育筛查测验(DDST)进行发育筛查。结果 61例中小于胎龄儿(SGA)27例(44.3%),适于胎龄儿(AGA)34例(55.7%)。随访1年,年龄别体重(WAZ)、年龄别身长(HAZ)、年龄别头围(HCZ)、身长别体重(WHZ)的Z积分中位数均>-1 SD;年龄别体质指数(BMI)的Z积分(BAZ)以及WHZ的高峰在纠正年龄1个月。纠正胎龄40周时,低体重、生长迟缓、消瘦、小头畸形、超重和肥胖等的生长偏离发生率最高,分别为15%、16%、11%、13%、20%和10%。与纠正胎龄40周比,纠正年龄6个月及9~12个月的超重发生率(3%,3%)明显降低(P P 结论 极低出生体重早产儿在纠正龄3个月以内生长偏离明显。生后第一年DDST筛查异常的比例较高。     

Growth and neurodevelopmental outcome of VLBW infants at 1 year corrected age

Objectives

To evaluate growth and neurodevelopmental outcome of very low birth weight infants (VLBW) and compare with term normal birth weight infants (NBW) till 12 months corrected age.

Design

A prospective cohort study

Setting

Tertiary care neonatal unit in northern India

Subjects

37 VLBW infants and 35 NBW infants born between January 2007 and December 2007.

Interventions

Anthropometric measurements were recorded and Z-scores were computed serially at birth, discharge, 40 weeks post menstrual age (PMA), and at 1, 3, 6 and 12 months of corrected age. Developmental quotient (DQ) at 12 months corrected age was assessed.

Results

Z-scores for weight, length and head circumference (HC) at birth were ?1.21(±0.92), ?0.98(±1.32) and ?0.70(±1.14), respectively for VLBW infants and ?0.37(±0.72), ?0.11(±0.96) and 0.05(±0.73) respectively for NBW infants. VLBW infants had a significant drop in all Z-scores by discharge (P<0.001). There was a catch up to birth scores by 12 month age. VLBW infants had significantly lower Z-scores for weight, length and HC at one year corrected age as compared to NBW infants (P =0.01, 0.04 and 0.001, respectively). DQ at 12 months was significantly lower in VLBW infants (91.5+7.8) than NBW infants (97.5±5.3) (P <0.001). DQ of small for gestational age (SGA) and appropriate for gestational age (AGA) VLBW infants was comparable.

Conclusion

VLBW infants falter in their growth during NICU stay with a catch-up later during infancy. In comparison to NBW infants, they continue to lag in their physical growth and neurodevelopment at 1 year of corrected age.     

Neurodevelopmental outcome and school performance of very-low-birth-weight infants at 8 years of age

The neurodevelopmental outcome and school performance of 50 appropriate for gestational age (AGA) and 33 small for gestational age (SGA) very-low-birth-weight (VLBW) infants, compared to a control group (41 Term infants) were assessed at 8 years of age. The incidence of major handicaps among AGA and SGA/VLBW infants respectively, was 16% and 6%. No major handicap was found in the control group. The incidence of neurodevelopmental abnormalities (NDA) among AGA's (40%) and SGA's (57.6%) compared with the control group (31.7%) was found to be significantly higher. School failure occurred more frequently among VLBW infants (22.9%) and was related in children with NDA — and more particularly among AGA's — to the presence of language disorders of associated NDA. Evaluation of the consequences of NDA and school problems for later academic and professional achievement now requires further follow-up studies.     

Glucose metabolism soon after birth in very premature infants with small- and appropriate-for-gestational-age birth weights

The intrauterine environment affects the development of insulin resistance in adulthood. To determine the influence of foetal growth restriction on glucose metabolism, we assessed indices of insulin sensitivity soon after birth in very premature infants. Blood samples were collected at birth from 52 premature infants with a gestational age of ≤31 weeks, who were divided into a group whose birth weight was small for their gestational age (SGA group, n=19) and a group whose birth weight was appropriate for their gestational age (AGA group, n=33). Blood glucose, serum insulin and C-peptide immunoreactivity (CPR) levels were measured in both groups. Furthermore, the quantitative insulin check index (QUICKI) was also calculated. Correlations between these indices and glucose metabolism and the standard deviation (SD) score for birth weight were also determined. The levels of insulin and CPR were significantly (p<0.05) lower in the SGA group than in the AGA group. The QUICKI was significantly (p<0.05) higher in the SGA group compared with the AGA group. The SD score for birth weight was correlated with the QUICKI (p<0.01), the serum insulin level (p<0.05) and the CPR level (p<0.05) in all 52 infants. Conclusion: In very premature infants, poor foetal growth may impair foetal insulin secretion and affect the QUICKI at birth.