Stress and lack of social support as risk factors for small-for-gestational-age birth

AIM: To determine the contributions of social support and perceived stress to the risk of small-for-gestational-age birth. METHODS: The investigation was a case-control study of mothers of infants born at 37 or more completed weeks of gestation. Cases weighed less than the sex-specific 10th percentile for gestational age at birth (small for gestational age (SGA), n = 836), and controls (appropriate for gestational age (AGA), n = 870) comprised a random selection of heavier babies. RESULTS: In univariate analyses measures of informal social support, but not perceived stress or formal social support, were associated with SGA birth. It was found that Asian mothers are less likely to receive support from families and friends. After adjustment for ethnicity, informal social support was not associated with SGA. CONCLUSIONS: Support appears to reduce the risk of SGA births, but after adjustment for ethnicity this is no longer the case. Stress during pregnancy was not associated with SGA birth.     

Risk factors for small-for-gestational-age babies: The Auckland Birthweight Collaborative Study

OBJECTIVE: This case-control study determined whether internationally recognized risk factors for small-for-gestational-age (SGA) term babies were applicable in New Zealand. METHODOLOGY: All babies were born at 37 or more completed weeks of gestation in one of three hospitals in Auckland. Cases weighed less than the sex specific 10th percentile for gestational age at birth, and controls (appropriate-for-gestational-age (AGA)) were a random selection of heavier babies. Information was collected by maternal interview and from obstetric databases. RESULTS: Information from 1714 completed interviews (844 SGA and 870 AGA) was available for analysis. Computerized obstetric records were available for 1691 of the 1701 women who consented to such access. In a multivariate analysis allowing for sex, gestational age at birth, social class and other potential confounders, mothers who smoked had a significantly increased risk of an SGA baby (adjusted OR 2.41; 95% CI 1.78-3.28), as did primiparous mothers (adjusted OR 1.34; 95% CI 1.03-1.73), mothers of Indian ethnicity (adjusted OR 3.22; 95% CI 1.95-5.30), women with pre-eclamptic toxaemia (adjusted OR 2.42; 95% CI 1.08-5.40) and those with pre-existing hypertension toxaemia (adjusted OR 5.49; 95% CI 1.81-16.71). Mothers of SGA infants were shorter (P < 0.001) and reported lower prepregnancy body weights (P < 0.001) than mothers of AGA infants. The population attributable fraction for smoking suggests that up to 18% of SGA infants born in the ABC Study could be related to maternal smoking. CONCLUSIONS: Risk factors associated with SGA births in other countries are also important in New Zealand. Smoking in pregnancy is an important and potentially modifiable behaviour, and efforts to decrease the number of women who smoke during pregnancy should be encouraged.     

妊娠期高血压疾病对胎龄28~34周早产儿外周静脉血细胞计数的影响

目的 探讨母亲妊娠期高血压疾病（hypertensive disorders of pregnancy,HDP）对胎龄28~34周早产儿外周静脉血细胞计数的影响。 方法 选取2020年1~12月昆明医科大学第一附属医院儿科收治的母亲合并HDP的胎龄28~34周早产儿227例为研究组,另选取同期收治的母亲无HDP的胎龄28~34周早产儿227例为对照组。研究组根据母亲妊娠期血压分为妊娠期高血压亚组（75例）、轻度子痫前期亚组（81例）、重度子痫前期亚组（71例）;根据早产儿出生体重分为小于胎龄儿（small for gestational age,SGA）亚组（113例）及适于胎龄儿（appropriate for gestational age,AGA）亚组（114例）。比较研究组和对照组、研究组各亚组间早产儿生后第1天外周血细胞计数的差异。 结果 研究组患儿生后第1天外周静脉血白细胞（white blood cell,WBC）计数、中性粒细胞绝对计数（absolute neutrophil count,ANC）及血小板（platelet,PLT）计数均低于对照组（P<0.05）,白细胞减少症、中性粒细胞减少症发生率高于对照组（P<0.05）。亚组分析中,轻度子痫前期亚组、重度子痫前期亚组WBC计数、ANC、PLT计数均低于妊娠期高血压亚组（P<0.05）;SGA亚组WBC计数、ANC、PLT计数低于AGA亚组（P<0.05）。 结论 HDP可对早产儿外周静脉血细胞计数产生影响,这一影响在母亲子痫前期及SGA早产儿中更为显著。     

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。     

Respiratory responses to hypoxia/hypercapnia in small for gestational age infants influenced by maternal smoking

Aim: To determine any variation in the respiratory responses to hypoxia/hypercapnia of infants born small for gestational age (SGA) to smoking and to non-smoking mothers. METHODS: A total of 70 average for gestational age (AGA) infants (>36 weeks gestation, >2500 g, >25th centile for gestational age, and no maternal smoking), and 47 SGA infants (<10th centile for gestational age) were studied at 1 and 3 months of age, in quiet and active sleep. Respiratory test gases were delivered through a Perspex hood to simulate face down rebreathing by slowly allowing the inspired air to be altered to a CO(2) maximum of 5% and O(2) minimum of 13.5%. The change in ventilation with inspired CO(2) was measured over 5-6 minutes of the test. The slope of a linear curve fit relating inspired CO(2) to the logarithm of ventilation was taken as a quantitative measure of ventilatory asphyxial sensitivity (VAS). RESULTS: There was no significant difference in VAS between the AGA and SGA infants (0.25 v 0.24). However within the SGA group, VAS was significantly higher (p = 0.048) in the infants whose mothers smoked during pregnancy (0.26 (0.01); n = 24) than in those that did not (0.23 (0.01); n = 23). The change in minute ventilation was significantly higher in the smokers than the non-smokers group (141% v 119%; p = 0.03) as the result of a significantly larger change in respiratory rate (8 v 4 breaths/min; p = 0.047) but not tidal volume. CONCLUSIONS: Maternal smoking appears to be the key factor in enhancing infants' respiratory responses to hypoxia/hypercapnia, irrespective of gestational age.     

Folate and intrauterine growth retardation

The objectives of this case-control study were to compare the levels of folate in cord and maternal blood of 315 mothers who had intrauterine growth-retarded (IUGR) babies and 321 mothers who had appropriate-for-gestational-age (AGA) babies, to evaluate the correlation between cord and maternal folate and to assess the prevalence of folate deficiency. Mothers were recruited from the four largest hospitals in Campinas city, south-east Brazil. The gestational ages of the newborns were evaluated by the Capurro method. They were classified as being IUGR according to the Lubchenco birthweight-for-gestational-age standard. Red blood cell (RBC) folate was measured by radio-immunoassay. Slightly more IUGR (25.7%) than AGA babies (19.9%) had cord folate levels < or = 226.5 nmol/l (100 ng/ml) (p = 0.05) and similar percentages of IUGR (32.1%) and AGA (29.9%) mothers had folate levels < or = 226.5 nmol/l. Mean cord folate levels in IUGR and AGA babies were 10% higher than mean folate levels in the two groups of mothers (p < 0.001). There were weak correlations between maternal and cord folate in IUGR (r = 0.31) and AGA (r = 0.35) (p < 0.001) mother/baby groups. In this population, 35% of mothers were folate-deficient although it was not associated with IUGR. Nevertheless, it would be important to give Brazilian women folate tablets during pregnancy and to investigate the effect on concentrations of homocysteine and on the prevalence of birth defects.     

Neurosonographic findings in premature infants and infants with intrauterine growth retardation with a birth weight below 1,500 grams]

The cranial ultrasound of 111 preterm infants were reviewed. 57 patients were appropriate for gestational age (AGA) and 54 small for gestational age (SGA). In the two groups, the incidence of peri-intraventricular hemorrhage (PIVH), posthemorrhagic ventricular dilation (VM) and peri-ventricular leucomalacia (PVL) was compared. PIVH was more common in AGA than in SGA babies (36.8% vs 18.5%). In both groups (AGA and SGA), birth weight less than 1000 g should be considered a further risk factor for hemorrhagic brain lesion (72.2% in AGA babies less than 1000 g and 20.5% ind AGA babies greater than 1000 g birth weight, p less than 0.01) (34.8% in SGA babies less than 1000 g and 6.4% in SGA babies greater than 1000 g birth weight, p less than 0.05). However, ischemic brain lesions (PVL) were not dependent from birth weight (p greater than 0.5). This study shows that low birth weight infants are an eterogeneous group of babies with different risk of hemorrhagic or ischemic cerebral lesion depending on gestational age and birth weight.     

Longitudinal investigation of the relationship between breast milk leptin levels and growth in breast-fed infants

BACKGROUND: It has been shown that leptin is present in breast milk and human mammary epithelial cells are able to synthesize leptin. It has been suggested that leptin in human milk might be involved in the regulation of postnatal nutrition and growth. AIMS: To investigate whether there is a relationship between leptin levels in human milk and weight gain in the postnatal period and to compare variations of milk-borne maternal leptin concentrations for small for gestational age (SGA), large for gestational age (LGA) and appropriate for gestational age (AGA) infants. INFANTS AND METHODS: Forty-seven healthy lactating women aged from 17-38 years and their infants were included in the study. The infants were separated into three groups according to birth weight as SGA (n = 11), LGA (n = 14) and AGA (n = 22). All infants were fed with breast milk during the study period. Anthropometric measurements were performed on the 15th day of life and at 1, 2, and 3 months of age, and the body mass index (BMI) of the infants' mothers was calculated. Breast milk leptin levels were analyzed by radioimmunoassay. RESULTS: Breast milk leptin levels were found reduced in the SGA group and increased in the LGA group compared to the AGA group at 15 days of life (13.4 +/- 2.2, 28.5 +/- 4.4 and 18.4 +/- 2 ng/ml, respectively; p <0.05). At 1 month of age, leptin levels in breast milk were significantly lower in the LGA group than in the AGA group (15.5 +/- 4.9, 19.4 +/- 1.7 ng/ml, respectively; p<0.05). There was no difference among the three groups at 2 and 3 months of age (p>0.05). There was a positive correlation between birth Weight and breast milk leptin levels on the 15th day (r = 0.47, p = 0.001). A negative correlation was found between weight gain during the first 15 days and 1 month of life and breast milk leptin levels on the 15th day (r = -0.44, p = 0.002; r = -0.40, p = 0.005, respectively). No relationship could be determined between breast milk leptin levels and BMI of the mothers. CONCLUSION: Maternal milk of SGA, LGA and AGA infants had different leptin levels, especially during the first month of life. More rapid growth was shown in the SGA infants during the first postnatal 15 days compared to AGA and LGA infants, and human milk leptin levels were significantly reduced in the SGA group. However, LGA infants gained more weight during the second 15 days of life and breast milk leptin levels were dramatically decreased in LGA and increased in SGA infants at the end of first month of life. These findings suggest that the presence of leptin in breast milk might have a significant role in growth, appetite and regulation of nutrition in infancy, especially during the early lactation period, and the production of leptin in breast tissue by human mammary epithelial cells might be regulated physiologically according to necessity and state of the infant.     

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.     

Growth in VLBW infants fed predominantly fortified maternal and donor human milk diets: a retrospective cohort study

ABSTRACT: BACKGROUND: To determine the effect of human milk, maternal and donor, on in-hospital growth of very low birthweight (VLBW) infants. We performed a prospective cohort study comparing in-hospital growth in VLBW infants by proportion of human milk diet, including subgroup analysis by maternal or donor milk type. Primary outcome was change in weight z-score from birth to hospital discharge. RESULTS: 171 infants with median gestational age 27 weeks (IQR 25.4, 28.9) and median birthweight 899 g (IQR 724, 1064) were included. 97% of infants received human milk, 51% received > 75% of all enteral intake as human milk. 16% of infants were small-for-gestational age (SGA, < 10th percentile) at birth, and 34% of infants were SGA at discharge. Infants fed >75% human milk had a greater negative change in weight z-score from birth to discharge compared to infants receiving < 75% (-0.6 vs, -0.4, p = 0.03). Protein and caloric supplementation beyond standard human milk fortifier was related to human milk intake (p = 0.04). Among infants receiving > 75% human milk, there was no significant difference in change in weight z-score by milk type (donor -0.84, maternal -0.56, mixed -0.45, p = 0.54). Infants receiving >75% donor milk had higher rates of SGA status at discharge than those fed maternal or mixed milk (56% vs. 35% (maternal), 21% (mixed), p = 0.08). CONCLUSIONS: VLBW infants can grow appropriately when fed predominantly fortified human milk. However, VLBW infants fed >75% human milk are at greater risk of poor growth than those fed less human milk. This risk may be highest in those fed predominantly donor human milk.     

Vascular retinal abnormalities in neonates of mothers who smoked during pregnancy

OBJECTIVE: To investigate whether maternal smoking during pregnancy causes retinal abnormalities in the newborn. STUDY DESIGN: One hundred sixty-two neonates of smoking mothers and 162 matched neonates of nonsmoking mothers (112 appropriate for gestational age [AGA], 30 small for gestational age [SGA], 20 large for gestational age [LGA] in each group) were studied. RESULTS: Retinal arterial narrowing and straightening (RANS) was observed in 52 and 10 eyes of the newborns of smoking and nonsmoking mothers, respectively (P <. 000001) in association with elevated blood pressure in the neonates. The frequency of RANS was more than 3-fold greater in the SGA neonates than in the AGA and LGA neonates of the smoking mothers. Retinal venous dilatation and tortuosity (RVDT) was found in 100 and 36 eyes of neonates of smoking and nonsmoking mothers, respectively (P <.000001). The frequency of RVDT in the SGA neonates of the smoking mothers was 2.5-fold and 4.2-fold greater than in the AGA infants and the LGA infants, respectively. Also, intraretinal hemorrhages were found in 61 and 31 eyes of neonates of smoking and nonsmoking mothers, respectively (P =.0007) in association with elevated hematocrit and RVDT, whereas no intraretinal hemorrhages were found when RANS was present. All retinal abnormalities resolved by 6 months in infants of smoking mothers and by 2 months in infants of nonsmoking mothers. CONCLUSIONS: Maternal smoking during pregnancy causes increased frequency of RANS, RVDT, and intraretinal hemorrhages; but these retinal abnormalities resolve by 6 months of age.     

Mother-infant feeding interaction in full-term small-for-gestational-age infants

Maternal and infant behavior during feeding was assessed in 30 mother-infant dyads: 15 small-for-gestational-age (SGA) infants (birth weights below the 10th percentile) and 15 appropriate-for-gestational-age (AGA) infants (birth weights between the 25th and 90th percentiles). The groups were balanced for gestational age, sex, neonatal risk factors, and maternal age, parity, socioeconomic status, and race. Behaviors indicative of infant feeding difficulties were coded for mother and infant. The SGA mothers had higher frequencies of these behaviors than did their AGA counterparts. Qualitative ratings of interactive behavior were recorded for mother and infant: SGA infants had ratings indicative of less optimal interactions than those of the AGA group. Infant caloric intake (calories per kilogram per feeding) was calculated by first dividing the change in infant weight in grams before feeding and immediately after feeding by the infant's weight before feeding and then converting it to calories. Although no difference in caloric intake was observed between the two groups, infant behaviors and ratings were associated with caloric intake. These data suggest the importance of including neonatal behavior during feeding in the risk assessment of potential growth failure in SGA infants.     

Children born small for gestational age are not at special risk for preschool emotion and behaviour problems

Despite the wealth of literature examining long term outcomes of preterm low birthweight children, few studies have directly assessed the developmental impact of being born full term but small for gestational age (SGA). We aim to determine whether (i) being SGA increases preschool behavioural problems and (ii) other risk factors operate differently in SGA and appropriate for gestational age (AGA) controls. 550 New Zealand European mothers and their 3.5 year old children participated in this study. All children were born at full term (>37 weeks' gestation) and approximately half were SGA (≤sex specific 10th percentile for gestation) the remainder were AGA controls. Extensive data were collected at the child's birth, 1 year and 3.5 years. Behavioural problems were measured when children were 3.5 years, using the Strengths and Difficulties Questionnaire (SDQ). Multiple regression analyses were used to examine the associations between risk factors and behavioural problems; statistical weighting was used for analyses of the total study group. There was no significant difference in behavioural problems between SGA and AGA groups. In the total sample the significant predictors of behavioural problems included: mothers' school leaving age; smoking during pregnancy; maternal alcohol use during pregnancy; and absence of the father. Predictors of behavioural problems were found to be the same for SGA and AGA groups. These results do not support the view that SGA is a risk for behavioural preschool difficulties or that SGA children are sensitised to risks known to be associated with such difficulties in the preschool years.     

Catch-up growth in infants born small for gestational age--a longitudinal study

BACKGROUND: Epidemiological studies correlate low birth weight and the subsequent development of diabetes mellitus (DM). Early changes in insulin resistance in infants with catch-up growth (CUG) have not been evaluated in our population. AIM: To identify dietary and metabolic features associated with CUG in infants born small for gestational age (SGA) at 1 year old. METHODS: In a cohort study of 88 term infants (44 SGA and 44 appropriate for gestational age [AGA]), breastfeeding and weaning age were registered. Anthropometric measurements, glucose, insulin, and leptin concentrations were measured at birth and at 1 year old. RESULTS: A history of DM in a second-degree relative (p = 0.01) and complementary breastfeeding (p = 0.0003) were higher in SGA compared to AGA infants. Ten (13.6%) infants showed CUG in length and weight combined. They had lower weight, glucose, IR index, and leptin concentrations at birth than those without CUG. After logistic regression analysis for factors related to weight CUG, gender, weaning age, birth weight and leptin concentration at birth were included in the model (R2 = 0.31; p = 0.00004). CONCLUSIONS: Female gender, early weaning, lower birth weight, and lower leptin concentration at birth are related to weight CUG in Mexican infants.     

Maternal folate,one‐carbon metabolism and pregnancy outcomes

Single nucleotide polymorphisms and pre‐ and peri‐conception folic acid (FA) supplementation and dietary data were used to identify one‐carbon metabolic factors associated with pregnancy outcomes in 3196 nulliparous women. In 325 participants, we also measured circulating folate, vitamin B12 and homocysteine. Pregnancy outcomes included preeclampsia (PE), gestational hypertension (GHT), small for gestational age (SGA), spontaneous preterm birth (sPTB) and gestational diabetes mellitus (GDM). Study findings show that maternal genotype MTHFR A1298C(CC) was associated with increased risk for PE, whereas TCN2 C766G(GG) had a reduced risk for sPTB. Paternal MTHFR A1298C(CC) and MTHFD1 G1958A(AA) genotypes were associated with reduced risk for sPTB, whereas MTHFR C677T(CT) genotype had an increased risk for GHT. FA supplementation was associated with higher serum folate and vitamin B12 concentrations, reduced uterine artery resistance index and increased birth weight. Women who supplemented with <800 μg daily FA at 15‐week gestation had a higher incidence of PE (10.3%) compared with women who did not supplement (6.1%) or who supplemented with ≥800 μg (5.4%) (P < .0001). Higher serum folate levels were found in women who later developed GDM compared with women with uncomplicated pregnancies (Mean ± SD: 37.6 ± 8 nmol L⁻¹ vs. 31.9 ± 11.2, P = .007). Fast food consumption was associated with increased risk for developing GDM, whereas low consumption of green leafy vegetables and fruit were independent risk factors for SGA and GDM and sPTB and SGA, respectively. In conclusion, maternal and paternal genotypes, together with maternal circulating folate and homocysteine concentrations, and pre‐ and early‐pregnancy dietary factors, are independent risk factors for pregnancy complications.     

Anthropometric assessment of nutritional status in newborn infants. Discriminative value of mid arm circumference and of skinfold thickness

74 appropriate-for-gestational age (AGA) and 22 small-for-gestational age (SGA) caucasian infants were studied for anthropometric parameters: mid arm circumference (MAC), triceps and subscapular skinfold thickness (TSKF and SSKF) recorded at 15 and 60 s, chest circumference (cc), head circumference, birth weight and length.MAC is highly correlated with birth weight either in AGA (r = 0.936; P < 0.001) or in SGA infants (r = 0.860; P < 0.001). MAC is also correlated with gestational age in AGA (r = 0.850; P < 0.001) and SGA infants (r = 0.76; P < 0.001). Similar correlations were found between TSKF, SSKF and birth weight or gestational age. Arm muscle and fat areas are also positively correlated with birth weight and gestational age, in AGA and SGA infants.A multiple regression analysis of our data allowed a classification of the best discriminant anthropometric parameters between AGA and SGA infants. MAC, SSKF15, SSKF60 and chest circumference were selected. An equation was established in AGA infants with these four parameters giving a predictive gestational age: gestational age (weeks) = 1.216 MAC (cm)?3.588 SSKF15 (mm)+0.263 CC (cm) + 17.9.The ratio of predicted gestational age to the real gestational age was 1.0 ± 0.044 in AGA versus 0.896 ± 0.034 in SGA infants.Our data suggest that MAC and SSKF provide a simple measure of body composition of neonates and a useful tool for determining the degree of maturity of a newborn independent of birth weight.     

Maternal selenium,copper and zinc concentrations in pregnancy associated with small‐for‐gestational‐age infants

Pregnancy during adolescence increases the risk of adverse pregnancy outcome, especially small‐for‐gestational‐age (SGA) birth, which has been linked to micronutrient deficiencies. Smoking has been shown to be related to lower micronutrient concentrations. Different ethnicities have not been examined. We used a subset from a prospective observational study, the About Teenage Eating study consisting of 126 pregnant adolescents (14–18‐year‐olds) between 28 and 32 weeks gestation. Micronutrient status was assessed by inductively coupled mass spectrometry. Smoking was assessed by self‐report and plasma cotinine, and SGA was defined as infants born <10th corrected birthweight centile. The main outcome measures were as follows: (1) maternal plasma selenium, copper and zinc concentrations in adolescent mothers giving birth to SGA vs. appropriate‐for‐gestational‐age (AGA) infants; and (2) comparison of micronutrient concentrations between women of different ethnicities and smoking habits. The plasma selenium {mean ± standard deviation (SD) [95% confidence interval (CI)]} concentration was lower in the SGA [n = 19: 49.4 ± 7.3 (CI: 45.9, 52.9) µg L^?1] compared with the AGA [n = 107: 65.1 ± 12.5 (CI: 62.7, 67.5) µg L^?1; P < 0.0001] group. Smoking mothers had a lower selenium concentration compared with non‐smokers (P = 0.01) and Afro‐Caribbean women had higher selenium concentrations compared with White Europeans (P = 0.02). Neither copper nor zinc concentrations varied between groups. Low plasma selenium concentration in adolescent mothers could contribute to the risk of delivering an SGA infant, possibly through lowering placental antioxidant defence, thus directly affecting fetal growth. Differences in plasma selenium between ethnicities may relate to variation in nutritional intake, requiring further investigation.     

The influence of gestational age, size for dates, and prenatal steroids on cord transferrin levels in newborn infants

Serum transferrin levels assess protein status in older children and adults. To generate standards for its use in newborn infants, we measured umbilical cord serum transferrin levels in 161 appropriate (AGA), 25 large (LGA) and 16 small (SGA) for gestational age infants between 25 and 43 weeks' gestation. We also assessed the effects of intrauterine growth, exposure to prenatal steroids, and presence of pulmonary maturity on neonatal transferrin levels. Cord transferrin levels in AGA infants were significantly correlated with increasing gestational age (r = 0.60; p less than 0.001). Infants born before 37 weeks' gestation had significantly lower transferrin levels, when compared with those born at term (p less than 0.001). LGA infants had significantly higher levels than age-matched AGA infants (253 +/- 75 vs. 214 +/- 53 mg/dl; p less than 0.025). Despite significantly lower mean birth weights (p less than 0.001), SGA infants also had significantly higher levels than gestational age-matched AGA controls (227 +/- 63 vs. 167 +/- 40 mg/dl; p less than 0.005). For infants less than 35 weeks' gestation, neither the 20 preterm infants with exposure to prenatal steroids (maternal betamethasone), nor the 26 infants with pulmonary maturity had significantly elevated transferrin levels, when compared with gestational age-matched control infants. Newborn transferrin levels correlate well with gestational age and are significantly affected by size for dates, but not by a brief course of prenatal steroids or by pulmonary maturity.     

Effects of gestation and birth weight on the growth and development of very low birthweight small for gestational age infants: a matched group comparison

AIMS: To investigate the effects of small for gestational age (SGA) in very low birthweight (VLBW) infants on growth and development until the fifth year of life. METHODS: VLBW (< 1500 g) infants, selected from a prospective study, were classified as SGA (n = 115) on the basis of birth weight below the 10th percentile for gestational age and were compared with two groups of appropriate for gestational age (AGA) infants matched according to birth weight (AGA-BW; n = 115) or gestation at birth (AGA-GA; n = 115). Prenatal, perinatal, and postnatal risk factors were recorded, and duration and intensity of treatment were computed from daily assessments. Body weight, length, and head circumference were measured at birth, five and 20 months (corrected for prematurity), and at 56 months. General development was assessed at five and 20 months with the Griffiths scale of babies abilities, and cognitive development at 56 months with the Columbia mental maturity scales, a vocabulary (AWST) and language comprehension test (LSVTA). RESULTS: Significant group differences were found in complications (pregnancy, birth, and neonatal), parity, and multiple birth rate. The AGA-GA group showed most satisfactory growth up to 56 months, with both the AGA-BW and SGA groups lagging behind. The AGA-GA group also scored significantly more highly on all developmental and cognitive tests than the other groups. Developmental test results were similar for the SGA and AGA-BW groups at five and 20 months, but AGA-BW infants (lowest gestation) had lower scores on performance intelligence quotient and language comprehension at 56 months than the SGA group. When prenatal and neonatal complications, parity, and multiple birth were accounted for, group differences in growth remained, but differences in cognitive outcome disappeared after five months. CONCLUSIONS: Being underweight and with a short gestation (SGA and VLBW) leads to poor weight gain and head growth in infancy but does not result in poorer growth than in infants of the same birth weight but shorter gestation (AGA-BW) in the long term. SGA is related to early developmental delay and later language problems; however, neonatal complications may have a larger detrimental effect on long term cognitive development of VLBW infants than whether they are born SGA or AGA.     

Body water content of extremely preterm infants at birth

BACKGROUND: Preterm birth is often associated with impaired growth. Small for gestational age status confers additional risk. AIM: To determine the body water content of appropriately grown (AGA) and small for gestational age (SGA) preterm infants in order to provide a baseline for longitudinal studies of growth after preterm birth. METHODS: All infants born at the Hammersmith and Queen Charlotte's Hospitals between 25 and 30 weeks gestational age were eligible for entry into the study. Informed parental consent was obtained as soon after delivery as possible, after which the extracellular fluid content was determined by bromide dilution and total body water by H(2)(18)O dilution. RESULTS: Forty two preterm infants were studied. SGA infants had a significantly higher body water content than AGA infants (906 (833-954) and 844 (637-958) ml/kg respectively; median (range); p = 0.019). There were no differences in extracellular and intracellular fluid volumes, nor in the ratio of extracellular to intracellular fluid. Estimates of relative adiposity suggest a body fat content of about 7% in AGA infants, assuming negligible fat content in SGA infants and lean body tissue hydration to be equivalent in the two groups. CONCLUSIONS: Novel values for the body water composition of the SGA preterm infant at 25-30 weeks gestation are presented. The data do not support the view that SGA infants have extracellular dehydration, nor is their regulation of body water impaired.