Limited clinical utility of midtrimester fetal morphometric percentile rankings in screening for birth weight abnormalities

OBJECTIVE: Our purpose was to determine whether midtrimester fetal ultrasonographic morphometric percentile rankings are sensitive screening tests for preterm labor or birth weight abnormalities. STUDY DESIGN: Stepwise multiple regression and chi 2 analysis were used to identify midtrimester fetal measurements predicting birth weight and gestational age. Receiver-operator characteristics curves were used to evaluate abdominal circumference percentiles as a test for large-for-gestational-age and small-for-gestational-age infants. RESULTS: Extremes in abdominal circumference and head measurement percentiles were associated with large- and small-for gestational-age infants but not with preterm delivery. Abdominal circumference predicted birth weight in regression analysis; however, receiver-operator characteristic curves showed abdominal circumference percentiles to be poor screening tests for large- or small-for-gestational-age infants. The positive predictive value of 10th and 90th abdominal circumference percentiles for small- and large-for-gestational-age infants was < 20%. CONCLUSION: Midtrimester percentile rankings offer no clear benefit in targeting fetuses with potential birth weight abnormalities or risk of preterm delivery and may provide clinically misleading information.     

Twenty-month outcome in ventilator-dependent, very low birth weight infants born during the early years of dexamethasone therapy

We sought to examine the effect of the introduction of dexamethasone therapy on health, growth, and neurodevelopmental outcome in very low birth weight (VLBW) infants at 20 months of age. We compared outcomes in all 86 VLBW infants (mean birth weight 871 gm, mean gestational age 26.4 weeks) who were ventilator dependent on day 21 of life during the 2 years preceding October 1988 (period 1), when dexamethasone therapy became accepted clinical practice in our unit, with outcomes in all 124 infants (mean birth weight 891 gm, mean gestational age 26.9 weeks) with similar ventilator status during the subsequent 2 years (period 2). In addition, we compared outcomes in infants who received dexamethasone during period 2 with those in a concurrent cohort of less ill infants who were not given dexamethasone. There were no significant differences between periods 1 and 2 in mortality rates after 21 days (17% vs 21%), need for home oxygen (23% vs 25%), oxygen dependence at 20 months of corrected age (11% vs 10%), rate of neurosensory impairment (24% vs 25%), and mean Bayley Mental scores (81.5 vs 77.2) or Psychomotor Development Index (81.6 vs 71.1). Infants who received dexamethasone during period 2 had significantly more severe lung disease and poorer respiratory, growth, and developmental outcomes. We conclude that VLBW infants with ventilator-dependent chronic lung disease have very poor outcomes, even when treated with dexamethasone. More information is needed from prospective, randomized trials before dexamethasone can be accepted as routine therapy for chronic lung disease.     

When they grow up: the growth of extremely low birth weight (< or = 1000 gm) infants at adolescence

The growth of 32 extremely low birth weight infants (1000 gm or less) was determined at adolescence. Their height, weight, and head circumference were measured twice in the first year of life and then at ages 2, 3, 5, 8, 10 years, and during adolescence (12 to 18 years). The mean height, weight, and head circumference of the adolescents were at the 50th percentile. Female heights were > or = their mothers; male heights were in the same or greater percentile than those of their fathers. Extremely low birth weight infants experience "catch-up" growth up to and into adolescence and attain predicted biparental genetic height.     

Postnatal changes of leptin levels in full-term and preterm neonates: their relation to intrauterine growth, gender and testosterone

The present study was carried out to investigate leptin levels in arterial and venous cord serum and in amniotic fluid in full-term infants at birth and on the 5th postnatal day to define the relationship of leptin to intrauterine growth rate, gender and early postnatal life. The relation of weight gain to serum leptin levels in male preterm infants was determined measuring leptin concentration weekly in the first 5 postnatal weeks. Testosterone levels were determined simultaneously to explore a possible relationship between leptin and testosterone concentrations. Fifty-three term newborn infants with mean birth weight and gestational age of 3,419 g (range 2,150-4,480) and 38.9 weeks (range 36-41) and 19 preterm male infants (mean birth weight and gestational age were 1,416 g (770-1,800) and 30.2 weeks (26-35) were enrolled into the study. Leptin and testosterone levels were determined by radioimmunoassay. It was demonstrated that serum leptin levels were markedly elevated in the cord blood without discernible arteriovenous differences. Cord blood leptin was found to correlate with birth weight (r = 0.40, p < 0.002), weight to length ratio (r = 0.40, p < 0.002) and body mass index (r = 0.35, p < 0.005). It was significantly lower in boys as opposed to girls (p < 0.01) and there was an apparent fall by the 5th postnatal day (p < 0.001). Amniotic fluid contained leptin in much less concentration than cord blood and it proved to be independent of intrauterine growth or gender. Serum leptin concentration in preterm infants at 1 week of age was significantly lower compared with term infants (p < 0.002) and it increased progressively with age (p < 0.01). An inverse relationship was found between leptin and testosterone level (r = -0.358, p < 0.01) and a positive correlation between leptin level and weight/height ratio (r = 0.674, p < 0.01). It is concluded that leptin derived either from placenta or fetal adipose tissue may be involved in regulating fetal growth and development and it may be related to energy intake, storage and expenditure. In preterm male infants serum leptin concentration increases with postnatal weight and testosterone may suppress leptin synthesis.     

Thyroid function in premature infants. The hypothyroxinemia of prematurity

Advances of perinatal and neonatal medicine have been associated with a progressive reduction in mortality of premature infants and a progressive increase in number of the surviving very low birth weight (VLBW) cohort less than 28 to 32 weeks gestation age. Hypothalamic-pituitary-thyroid (HPT) function is immature in most premature infants, and this is particularly true of the VLBW group. Accumulated information has allowed development of a unique nosology of HPT system disorders in these infants to facilitate thyroid function testing, test interpretation, and patient management.     

Composition of peripheral blood progenitor cell components collected from healthy donors

OBJECTIVES: The purpose of this study was to test the hypothesis that low circulating thyroxine concentrations characteristic of very low birth weight (VLBW) neonates (< 1500 g) are the result of decreased protein binding of thyroid hormones and to elucidate the mechanism(s) responsible and possible significance thereof. DESIGN: Cross-sectional comparison of thyroid related measurements in cord blood specimens from VLBW infants and from full term infants. Longitudinal comparison in cord and 2- and 4-week blood specimens from VLBW infants. PATIENTS: Cord blood specimens were analysed from 47 VLBW and 45 full term infants weighing > or = 2500 g. Repeat analyses in venous bloods from 32 of the VLBW infants were analysed at 2 weeks of age and again at 4 weeks in 23. The first cohort of patients was studied in 1994 and comprised 28 VLBW and 24 full term infants (Cohort A). The studies were repeated in 1995-96 in 19 VLBW infants and 21 full term infants (Cohort B). MEASUREMENTS: T4, free T4 (FT4), T3, thyroxine binding globulin (TBG), and TSH were measured in cord blood and 2- and 4-week venous specimens from VLBW infants and in cord blood specimens of full term infants. Molar ratios of T4/TBG were calculated. RESULTS: (1) Cord blood TBG, T4 and T3 concentrations of VLBW infants were each 60% of those of term infants. TBG concentrations were 397 +/- 111 vs 680 +/- 172 nmol/l (P < 0.0005). T4 concentrations were 76 +/- 22 vs 139 +/- 26 nmol/l (P < 0.0005). FT4 concentrations were in the normal adult range in both neonatal groups. T4/TBG ratios did not differ between the neonatal groups but were significantly less than that of adults (P < 0.001). (2) TSH concentrations in VLBW infants at 2 and 4 weeks were less than 50% of cord blood values. At 2 weeks, TBG concentrations of VLBW infants were unchanged from cord blood concentrations but mean T4 concentration fell by 18% and T4/TBG ratios by 21% (P < 0.005). Mean FT4 rose by 78% (P < 0.02). The changes in mean T4 and FT4 were due largely to FT4 concentrations of 37-113 pmol/l and T4 concentrations of 13-48 nmol/l in 5 infants. These infants also had lower T4/TBG ratios and were smaller and more ill than the remainder of the cohort. The changes disappeared by 4 weeks in 3 of the 4 infants tested. CONCLUSIONS: Cord T4/TBG ratios are the same in very low birth weight and term infants and are significantly lower than in adult blood. These are more than compensated for in term infants by a 236% increase in thyroxine binding globulin concentrations. The lower thyroxine binding globulin concentrations in very low birth weight infants explain their much lower T4 concentrations. Cord FT4 concentrations of full term and very low birth weight infants are in the normal adult range. T4 concentrations are further depressed and free T4 concentrations elevated in the most ill very low birth weight infants at 2 weeks of age in a manner analogous to that of the 'sick euthyroid syndrome'.     

Combined effects of antenatal corticosteroids and surfactant supplementation on the outcome of very low birth weight infants

Antenatal corticosteroids in preterm pregnancy may result in the reduction of the incidence of respiratory distress syndrome (RDS) and neonatal mortality. It is well known that postnatal use of surfactant in very low birth weight (VLBW) infants with RDS results in decreased neonatal morbidity and mortality. To evaluate the additive beneficial effects of combined antenatal corticosteroids and postnatal use of rescue surfactant on the outcome of VLBW infants, we retrospectively reviewed 286 maternal/infant charts of preterm infants with gestational ages 23 to 32 weeks and birth weights 501 to 1500 gm who were born at our institution from 1991 through 1994. Of the 87 (30%) infants who were treated with corticosteroids before birth, 41 (47%) had RDS, and of the 199 (70%) infants who were not treated with corticosteroids before birth, 162 (81%) had RDS (p < 0.001). The infants who had RDS and who were treated with corticosteroids before birth had a decreased incidence of pulmonary air leaks and a decreased need for diuretic therapy. In addition, they had a significant reduction in O2 requirement and ventilator settings as reflected by FIO2, mean airway pressure, ventilator rate, O2 index, and A-aDO2 before they received the first dose of rescue surfactant (p < 0.05 to p < 0.01) in contrast to other VLBW infants who had RDS and who were not treated with corticosteroids before birth. We conclude that antenatal corticosteroid therapy in threatened premature labor combined with the use of postnatal rescue surfactant is associated with a decreased incidence of RDS and may be beneficial for reducing the severity of RDS and improving the eventual outcome of VLBW infants.     

Follow-up study on physical and mental development in small-for-gestational age infants

A follow-up study on physical and mental development was carried out in 35 small-for-gestational-age (SGA) and 35 appropriated-for-gestational age (AGA) infants. Excluded for congenital abnormality, intrauterine infection, and neonatal asphyxia SGA and AGA infants were similar in maternal education level, infant sex, illness, and feeding history. The results revealed that the body weight (8.09 +/- 0.73kg), height (69.55 +/- 2.49 cm), head circumference (43.27 +/- 1.67cm), Kaup index (16.17 +/- 1.05), and development quotient (96.37 +/- 5.76, Gesell diagnostic method) level at 40 weeks of age in SGA infants was lower than that in AGA infants (P < 0.001), and the development quotient (DQ) in SGA infants was especially low in language and receptive regions. Cord serum insulin level was significantly correlated with follow-up body weight, height, and DQ level (P < 0.01). This article proposed that infants with intrauterine growth retardation have a physical development delay at 40 weeks of age, and which could be predicted by measuring cord insulin level.     

Secular changes in standards of bodily attractiveness in women: tests of a reproductive model

In very low birth weight (VLBW) infants careful growth and nutritional supervision are necessary in order to reduce the incidence of persistent growth retardation after 2 to 3 years of age. Recently, post-discharge formulas with higher protein, energy and mineral content has been developed with the aim to promote catch up growth and mineral accretion during the first months of life. Based upon the most recent nutritional and growth data, the authors propose guidelines for the nutrition and growth follow-up of VLBW infants after discharge from the neonatal unit.     

A fiberscopic analysis of velopharyngeal movement before and after primary palatoplasty in cleft palate infants

The usefulness of bioelectrical impedance (BI) with anthropometry to measure total body water (TBW) was evaluated in very-low-birth-weight (VLBW) infants. A specific regression equation to measure TBW in a VLBW population was developed by simultaneously using the H2[(18)O] dilution method and BI in 12 infants with a gestational age of 24-30 wk and weighing <1200 g at birth. After an oral dose of H2[(18)O], the tracer dilution was measured in expired carbon dioxide. BI measurements were made with a model BIA-101 apparatus (RJL Systems, Detroit). Electrodes were placed in the standard position as well as proximally on the leg and the forearm. The best correlation was observed between body weight and TBW (r = 0.989). For BI, the best correlation was obtained when gestational age was used as a covariable along with body weight and crown-heel length (r = 0.985). The correlation was comparable with proximal electrode placement (r = 0.985). The new correlation was evaluated in 6 infants weighing < 1008 g. A significant correlation between BI and H2[(18)O]-measured TBW was observed (r = 0.988). Published regression equations for infants consistently gave higher estimates of TBW in another group of 14 infants weighing <1200 g than did the new correlations. TBW represented 84-95% of body weight in these VLBW infants. TBW could be computed simply from body weight alone. Use of BI and length as covariables did not add significantly to the estimate of TBW in VLBW infants.     

Normal weight for length in newborn infants in whom growth hormone deficiency was later diagnosed. Swedish Paediatric Study Group for GH Treatment

A new model for evaluating leanness/fatness (LeanSDS) in the newborn infant has been used to examine body weight for length in a group of Swedish infants in whom idiopathic growth hormone deficiency (GHD n = 220) was later diagnosed. These infants have earlier been reported to be significantly shorter (median = -0.87 SDS; SDS; standard deviation scores) and lighter (median = -0.60 SDS) in relation to gestational age, than the most recent reference. A group of infants who later developed GHD due to organic etiologies (n = 92) had normal weight and length for gestational age at birth. Using the LeanSDS model (with intercept 0.0 and regression coefficient 0.7) revealed that these idiopathic GHD infants have weight that is normal for their length (mean LeanSDS = 0.11 +/- 0.08 (SEM); n.s.) why the abnormality is a reduced linear growth. These findings also indicate that birth length (linear growth) should be given increased attention when size at birth is evaluated.     

Neonatal outcome in infants with evidence of fetal exposure to opiates, cocaine, and cannabinoids

This study evaluated the neonatal outcome of infants with evidence of fetal exposure to cocaine, opiates, and cannabinoids. Subjects were from the newborn nursery of an inner-city university teaching hospital. Meconium from 141 infants admitted to the full-term nursery was analyzed for metabolites of opiates, cocaine, and cannabinoids. The population was 72% African-American; 82% had medical assistance; history of drug use was reported in the medical records in 18%; mean maternal age was 24.2 years; mean birth weight was 3,234 +/- 502 g; and neonatal abstinence syndrome was reported in 7%. Meconium analysis data showed the following: 52.5% were drug-free; cocaine was present in 31%, opiates in 18% (cocaine and/or opiates 39%), and cannabinoids in 17%. In 38 infants in whom urine toxicology was obtained for clinical indications, meconium was more sensitive than urine in detecting drug exposure (55.3% vs 31.5%). There was no significant difference between cocaine/opiate-exposed and drug-free infants in race, socioeconomic status, maternal age, birth weight, head circumference, length, and Apgar scores. Cocaine/opiate-exposed infants had greater length of stay and increased frequency of maternal sexually transmitted diseases during pregnancy, with a trend toward a higher percent with fetal distress.     

WAY 100,635 enhances both the ''antidepressant'' actions of duloxetine and its influence on dialysate levels of serotonin in frontal cortex

Over a 6-year period (1989-1995), gastrointestinal (GI) perforation was diagnosed in nine preterm infants (mean gestational age 27 weeks, mean birth weight 872 g). Three presented with necrotizing enterocolitis (NEC), two with indwelling-tube-induced perforation of the stomach, one with small-left-colon syndrome, and another with meconium ileus. Spontaneous intestinal perforation occurred in two similar very-low-birth-weight (VLBW) infants, in the distal ileum, on days 8 and 9 of life, respectively. The only clinical sign was extensive abdominal distension, and abdominal X-ray studies revealed free peritoneal air. All findings were distinct from those associated with NEC. Their further clinical course was complicated by reperforation on day 32 and 39, respectively. They subsequently recovered and presented without GI problems at the corrected ages of 4 and 2 months, respectively. In contrast to high mortality of 57% in the group with non-spontaneous intestinal perforations, spontaneous perforation seems to have a good prognosis even in VLBW infants if diagnosed and treated promptly.     

Advances in molecular diagnosis

We evaluated bone density in term and preterm infants using computed x-ray densitometry, which permits measurement of bone density with minimal disturbance to the infants in their incubators. Bone density, bone width, and bone length of the right radius were determined in 155 infants of appropriate weights for their gestational ages (23 to 41 weeks). A curve for intrauterine bone growth was extrapolated from these data. The mean coefficients of variations for variabilities for intra- and interobserver error for all measurements were < 3.5%. In 18 infants, measurements of the right forearm were obtained in two positions to confirm the validity of densitometric measurements. The mean coefficients of variation were 3.42% for bone density, 3.48% for bone width, and 0.21% for bone length. Bone density was significantly correlated with gestational age (r = 0.924) and birth weight (r = 0.921). Bone width and length were also correlated with gestational age (r = 0.866 and 0.937) and birth weight (r = 0.878 and 0.954). Our results suggest that computed x-ray densitometry is a useful method for evaluation of bone density in preterm infants, including those in an intensive care environment.     

Variants in the growth of meningiomas of the base of the skull spreading into the orbit and paranasal sinuses]

PURPOSE: To determine differences in temperature for very low birth weight (VLBW) infants when swaddled and unswaddled in heated, double-walled incubators. DESIGN: A crossover design was used with infants receiving both the swaddled and unswaddled conditions. SAMPLE: 15 very low birth weight infants (< 1,500 gms) with postconceptional ages of 29.1 +/- 1.5 weeks. MAIN OUTCOME VARIABLE: Infant temperature in swaddled and unswaddled conditions. RESULTS: Abdominal temperatures during swaddling were 0.2 degree C higher than the unswaddled condition. In the swaddled condition, infants required a lower incubator temperature (mean = 26.9 +/- 0.4) than when unswaddled (mean = 29.8 +/- 0.5).     

Different developmental courses for very-low-birthweight infants differing in early head growth.

Investigated the utility of using measurements of the head circumference (HC) change in very-low-birthweight (VLBW) infants to assess the adequacy of brain growth. VLBW Ss (weighing     

Nutritional outcome of 207 very low-birth-weight infants in an intensive care unit

Growth and feeding outcomes during the first weeks of life were prospectively evaluated in 207 critically ill, very low-birth-weight (VLBW) infants (birth weight less than 1,500 gm). Maximal weight loss occurrd by day 9, averaging 13 percent of birth weight, while birth weight was regained by day 18. Energy intake during initial weight gain (19 gm. per day) averaged 100 kcal per kilogram. Feeding and growth outcome were highly correlated (p of less than 0.001) with severity of illness but were not significantly related to sex, birth weight, or appropriateness of weight for gestational age.     

Randomised controlled trial of L-carnitine as a nutritional supplement in preterm infants

AIMS: To evaluate the effect of L-carnitine supplementation (25 mg/kg/d) on the growth and incidence of hypoglycaemia in preterm infants. METHODS: A double blind, placebo controlled randomised trial, stratified for gestational age, was conducted of 86 preterm infants between 28 and 34 gestational weeks. The median gestational ages in the carnitine group and placebo groups were 30.7 weeks (range 28.0 to 33.6) and 31.4 weeks (range 28.0 to 33.9), respectively. The median birthweights were 1.557 kg (range 0.944 to 2.275) and 1.645 kg (range 0.885 to 2.545), respectively. RESULTS: Mean plasma free carnitine concentrations were below values for normal term infants in both groups on day 1 (carnitine group 44.8 mumol/l, placebo group 25.5 mumol/l) in the placebo group on day 7 (50.7 mumol/l), but in neither group on days 14 and 28. Total, free, and acylcarnitine concentrations were significantly increased in both urine and blood in the L-carnitine group. There was no significant difference between the placebo and carnitine supplemented groups in growth rate, as assessed by weight, length, skinfold thickness and head circumference measurements, or in the incidence of episodes of hypoglycaemia. CONCLUSION: The addition of carnitine as a nutritional supplement at a dose of 25 mg/kg/day did not improve growth in our group of preterm infants nor protect them from episodes of hypoglycaemia.     

A safer and more effective treatment regimen for eclampsia

The purpose of our investigation was twofold: to provide normative data for the ratios between head circumference and cerebellum, abdominal circumference and cerebellum, and femur length and cerebellum; and to evaluate the predictive accuracy of an abnormal ratio in the detection of growth retardation and macrosomia. Data on 675 women with normal gestations between 14 and 42 weeks were used to estimate reference curves for the three ratios to be evaluated. We then compared the ratios of 34 fetuses with intrauterine growth retardation and 28 macrosomic fetuses to the control group. Of the three ratios that we investigated, abdominal circumference to transverse cerebellar diameter was the most efficacious. However, the sensitivity of this ratio for the detection of intrauterine growth retardation and macrosomia was only 52.9% and 46.6%, respectively. A ratio between head circumference, abdominal circumference, or femur length and the transverse cerebellar diameter cannot reliably distinguish between normally growing fetuses and those that are growth retarded or macrosomic.