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。     

Effect of neonatal caloric deprivation on head growth and 1-year developmental status in preterm infants

The effects of neonatal illness and caloric intake on head growth velocity and on 1-year developmental outcome were studied in 73 appropriate (AGA) and small for gestational age (SGA) premature infants of (mean +/- SD) 30 +/- 2 weeks gestation who received intensive care during the neonatal period. Head growth from birth to 1 year of corrected age was characterized by a triphasic curve initiated by a period of growth arrest or suboptimal growth followed by a period of catch-up growth and terminated by a period of growth along standard curves. Head growth arrest or suboptimal head growth were directly related to the duration of the initial period of caloric deprivation (less than 85 kcal/kg/day) and to the duration of mechanical ventilation. Catch-up head growth was influenced by the duration of the preceding period of caloric deprivation in all infants and by the caloric intake during that phase only in SGA infants; catch-up growth was unrelated to the duration of mechanical ventilation. Head growth along standard curves occurred in all infants by 3 months of corrected age and persisted up to 1 year of corrected age. Infants calorically deprived the longest (AGA 4 to 6 weeks, SGA 2 to 3 weeks) had head growth along standards at curves below -1 SD on the growth chart; all other groups had this phase of head growth at curves between the mean and -1 SD. Infants calorically deprived for more than 4 weeks had developmental scores below normal ranges by 1 year of corrected age.     

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.     

Maternal and umbilical cord serum leptin concentrations in small-for-gestational-age and in appropriate-for-gestational-age neonates: a maternal,fetal, or placental contribution?

Leptin is secreted during pregnancy by the placenta and by the maternal and fetal adipose tissues. The leptin levels mainly reflect the amount of fat stored and thus are indicative of the energy balance, i.e., small-for-gestational-age (SGA) neonates represent the negative metabolic balance of in utero starved babies. We chose to compare maternal and umbilical cord leptin levels in pregnancies complicated by asymmetrical SGA versus those with appropriate-for-gestational-age (AGA) neonates as well as a model of multifetal growth concordant gestations in order to establish through the 'leptin link' the relative contributions of mother, fetus, and placenta to fetal weight. We found that the maternal leptin levels at delivery correlated poorly with the maternal weight gain/body mass index and with neonatal birth weight. Furthermore, the umbilical cord leptin levels correlated well with neonatal and placental weights in the AGA group but not in the SGA group. As in AGA singleton pregnancies, in multifetal uncomplicated pregnancies, the umbilical cord leptin levels correlated well with the birth weight of individuals, regardless of the status of the twin or triplet in the set. Thus, we speculated that in SGA neonates the birth weight represents the lean body weight and the low adipose tissue content (as opposed to the AGA neonates who have a substantial adipose tissue content) and, therefore, reflects mainly the basic placental contribution.     

Fetal and neonatal mortality of small-for-gestational age infants

Fetal and neonatal mortality of small-for-gestational age (SGA) infants in 1968–1982 were studied in the region of the University Central Hospital of Turku, Finland. During the study period, there were 254 fetal and 127 neonatal deaths in SGA infants. The fetal mortality rate of SGA infants declined from 49.9/1000 to 14.0/1000. The neonatal mortality rate of SGA infants declined from 23.8/1000 to 8.3/1000. The severely SGA infants with a birth weight below the 2.5th percentile had three times higher neonatal mortality rates than SGA infants with a birth weight between the 2.5th and the 10th percentiles. The main causes of fetal deaths were maternal diseases, placental and cord complications and fetal malnutrition, even though there was a decline in all these groups. Malformations remained the main cause of neonatal death during the study period, while there was a decline in deaths due to asphyxia and respiratory distress syndrome (RDS). The high mortality rates of SGA infants emphasize the need for early diagnosis and special attention during pregnancy, delivery and the neonatal period.Abbreviations SGA small-for-gestational age - AGA appropriate-for-gestational age - UCHT University Central Hospital of Turku - RDS respiratory distress syndrome     

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.     

High risk appropriate for gestational age (AGA) and small for gestational age (SGA) preterm infants. Neurological handicap and developmental abnormalities at five years of age

Outcome at five years of age of 110 high risk AGA, 71 high risk SGA preterm infants with similar birth weight and 102 term control infants was studied. Mean IQ in the 3 groups was not statistically different. Major handicaps were found in 16.3% of the AGA and in 8.5% of the SGA preterms. There was no major handicap among the controls. Minor neurodevelopmental abnormalities were present in 25.6% of AGA, 28.2% of SGA and 19.6% of controls. The types of neurodevelopmental handicaps were different in the 3 groups and generally more severe in the AGA group. All the major handicaps among AGA preterms were found in children with severe neonatal complications. In the SGA preterm group, only 1/3 of the major handicaps can be related to perinatal complications. Affective and behavior disorders were probably related in some way to neurodevelopmental achievement. This study showed that preterm infants with GA less than or equal to 32 weeks are more at risk than more mature SGA preterms with similar birth weight.     

Neurological development of small-for-gestational age babies during the first year of life

137 small-for-gestational age (SGA) infants were examined in the neonatal period and at 2, 6 and 12 months. At each age a structured assessment was used for which a score denoting neurological maturation could be given. The SGA infants were significantly retarded compared with average-for-gestational age (AGA) infants from 2 months onwards. Within the SGA group the mean scores for boys, those who were first-born, breast-fed and/or born to mothers who smoked during pregnancy were in each case significantly higher than the rest at 6 and 12 months. Maternal smoking influenced all aspects of development at 12 months; whereas sex and method of infant feeding mainly affected the motor items, and birth order only those that were socially oriented. Positive associations were found between changes in somatic measures and changes in neurological scores from birth through to 6 months. Infants who grew faster also matured faster during this period of time, and vice versa. Positive correlations were found between size and scores at 2 and 6 months, but not at 12 months.     

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.     

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。     

Bone, lean and fat mass of newborn twins versus singletons

AIM: Twin gestations are associated with disturbed fetal growth. The aim of this study was to compare body composition measurements of twins to those of singletons. METHODS: Anthropometric and dual energy X-ray absorptiometry (DXA) measurements were performed in twins and in matched singleton neonates. There were 48 pairs of twins in which 76 infants were appropriate for gestational age (AGA) with birth weights between the 10th and 90th percentile and 20 were small for gestational age (SGA) with birth weights <10th percentiles. Each AGA twin was matched as closely as possible for birth weight to an AGA singleton. Each SGA twin was matched with two cohorts of AGA singletons: one with similar birth weight and one with similar gestation. RESULTS: For AGA twins and their singleton cohort matched for birth weights, profile analysis using repeated measure analysis of variance showed that there were no significant differences in bone, fat and lean mass either as absolute values or as percentage of total weight. This was also the case for body composition of SGA twins compared to singletons matched for birth weight. In contrast, SGA twins have significantly lower absolute amounts of lean with tendency to lower fat and bone mass. CONCLUSION: For clinically normally grown neonates, with comparable weight, the body composition with respect to bone, fat and lean mass components are similar regardless whether they are products of singleton or twin pregnancies.     

Differential patterns of development: the interaction of birth weight, temperament, and maternal behavior.

A short-term longitudinal study of 83 families compared patterns of development between full-term small for gestational age (SGA) and normal birth weight (NBW) infants. Data were collected on infant temperament and maternal interaction at 3 and 6 months, and infant developmental outcomes at 6 months in order to investigate relationships between infant and maternal behavior, and developmental outcomes as a function of birth weight. Findings revealed few differences between SGA and NBW groups. However, the relations between infant temperament and maternal behavior varied as a function of birth weight and home environment. Specifically, more positive home environments were associated with higher ratings of maternal behavior and lower levels of infant negative reactivity for SGA but not for NBW infants. In addition, higher negative reactivity was related to lower performance on both the mental and psychomotor scales of the Bayley Scales of Infant Development (BSID), with stronger associations reported for SGA infants than for NBW infants.     

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.     

Association between serum leptin and anthropometric parameters at birth and at 15th day of life in infants born asymmetrically small for gestational age

The aim of this study was to investigate changes in skinfold measurements taken at three sites, mid-arm circumference and umbilical circumference during the first 15 days of life; and to evaluate relationships between anthropometric measurements and umbilical cord blood serum leptin levels in infants born small for gestational age (SGA) and appropriate for gestational age (AGA) infants. Of 50 newborn infants, 25 were SGA and 25 were AGA. Neonates' weight, mid-arm circumference (MAC), umbilical circumference (UC), and triceps, subscapular and periumbilical skinfold thicknesses were measured (Holtain callipers) immediately after delivery. Anthropometric parameters were measured again at 15th days of age. At birth, mean birth weight, mean skinfold thickness, MAC and UC measurements in the AGA group were significantly higher than those of the SGA group. These differences were also found on the 15th day. Birth weight correlated with all skinfold thicknesses, MAC and UC at birth. Weight at 15th day of life correlated with skinfold thicknesses, MAC and UC at 15th day of life. Cord blood leptin level was significantly lower in the SGA than in the AGA infants. This difference continued on the 15th day. When cord blood leptin level was compared with that of the 15th day, we found that leptin levels in the cord blood were significantly higher. There were significantly positive correlations between leptin levels and birth weight and skinfold thicknesses when the infants were all grouped together. When the newborns were grouped according to birth weight, there were positive correlations between cord blood serum leptin levels and these parameters in the AGA group, but no correlation in the SGA group. At the 15th day of life serum leptin levels correlated with weight, subscapular and triceps skinfold thickness in the AGA group, but only with triceps skinfold thickness in the SGA group.     

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.     

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。     

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.     

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.     

Growth of premature infants fed own mother's milk supplied with two milk formulas

The purpose of the authors in this article was to evaluate the effects of supplementing maternal milk with two different caloric formulas on the growth of premature newborns until they reached 40 weeks of post-conceptional age. Seventy premature infants weighing < 1750g at birth were randomized: 35 adequate for gestational age (AGA) and 35 small for gestational age received maternal milk and either a special preterm formula or a modified formula. Anthropometric measurements and clinical evaluations were used to determine the nutritional status and the postnatal growth of these infants, who were analyzed in six different moments: at maximum weight loss, at return to birth weight, at definite weight gain, when exclusively fed with formula, at 2000g, and when they reached 40 weeks of post-conceptional age. The AGA premature newborns on preterm formula had greater daily weight gain, cephalic circumference increase and growth. The SGA premature newborns on preterm formula had greater daily weight gain and cephalic circumference increase observed from the third week of life onward. The AGA premature newborns on modified formula had less weight gain and smaller increments in the cephalic circumference. The SGA premature on modified formula had the worst anthropometric results. The preterm formula was more efficient than the modified formula in promoting postnatal growth of AGA and SGA premature infants. We believe that, due to their special characteristics, SGA premature should receive individualized nutritional caloric planning     

Interaction and development in the first year. II. The effects of intrauterine growth retardation

Nine small-for-gestational age (SGA) and 10 appropriate-for-gestational age (AGA) fullterm infants were assessed using the Bayley MDI scale at 10 months, and infant-mother interactions observed at 6 months. Relationships among interaction parameters and development were compared with those of earlier interactions and development. At 6 months SGA and AGA mothers behaved similarly in interaction; SGA infants were more passive than AGA infants and demonstrated higher levels of state change. AGA infant vocalising frequencies at 2, 3 and 6 months were negatively related to MDI scores whereas maternal stimulation was positively related. Aspects of early SGA infant activity were negatively related to 10 month development; at 6 months several variables expressing dyadic interaction were negatively related. Ten month MDI scores were lower for the SGA than the AGA group. Socioeconomic status was related to MDI scores for AGA but not SGA infants. The results suggest that AGA and SGA infants behaved differently in interaction and that differential interaction patterns were linked with optimal development. Maternal stimulation and co-ordinated infant signalling in AGA dyads, and infant quietness and maternal activity encouraging quietness in SGA dyads, were patterns in high-scoring subjects. The exploratory nature of the study is noted.