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Summary: Background: Infants born very preterm experience poor postnatal growth relative to intrauterine growth, but at term equivalent age, they have increased percentage body fat compared with infants born at term. Objectives: The aim of this study was to assess body composition in very preterm infants born before 32 weeks postmenstrual age and to compare this with infants born at 32–36 weeks of gestation. Methods: Percentage fat, fat mass and fat‐free mass were measured in 87 very preterm infants born <32 weeks of gestation and studied at 32–36 weeks and in 88 control infants born at 32–36 weeks of gestation and measured on days 2–5 postnatally. Results: At 32–36 weeks, very preterm infants were lighter and shorter, had significantly greater percentage fat and absolute fat mass and had a significantly lower absolute fat‐free mass than the control group. The trajectory in percentage fat over increasing postnatal age in very preterm infants was closely aligned to that in term infants. Conclusions: Infants born very preterm accumulate fat rapidly after birth and have a deficit in fat‐free mass. Fat accumulation may be triggered by birth or associated events. If this rapid fat accretion is not taken into account, assessment of growth based on weight alone will underestimate the deficit in fat‐free mass. [ABSTRACT FROM AUTHOR]

Background: Maternal triglycerides are increasingly recognised as important predictors of infant growth and fat mass. The variability of triglyceride patterns during the day and their relationship to dietary intake in women in late pregnancy have not been explored. This prospective cohort study aimed to examine the utility of monitoring capillary triglycerides in women in late pregnancy., Methods: Twenty-nine women (22 with gestational diabetes (GDM) and 7 without) measured capillary glucose and triglycerides using standard meters at home for four days. On two of those days, they consumed one of two standard isocaloric breakfast meals: a high-fat/low-carbohydrate meal (66% fat) or low fat/high carbohydrate meal (10% fat). Following the standard meals, glucose and triglyceride levels were monitored., Results: Median capillary triglycerides were highly variable between women but did not differ between GDM and normoglycaemic women. There was variability in capillary triglycerides over four days of home monitoring and a difference in incremental area under the curve for capillary triglycerides and glucose between the two standard meals. The high-fat standard meal lowered the incremental area under the curve for capillary glucose ( p < 0.0001). Fasting (rho 0.66, p = 0.0002) and postpradial capillary triglycerides measured at home correlated with venous triglyceride levels., Conclusions: The lack of differences in response to dietary fat intake and the correlation between capillary and venous triglycerides suggest that monitoring of capillary triglycerides before and after meals in pregnancy is unlikely to be useful in the routine clinical practice management of women with gestational diabetes mellitus.

Background and Objective: The mechanism of reported benefits of delayed cord clamping (DCC) are unclear. We aimed to determine whether DCC compared to immediate cord clamping (ICC) in very preterm infants improves cerebral oxygenation in the first 24 h., Study Design: This is a prospective study of a subset of infants at < 30 weeks of gestation who were randomised to DCC (≥60 s) or ICC (< 10 s) and required an indwelling arterial catheter. Regional cerebral oxygenation (rScO2), blood pressure, PI, and peripheral saturation were measured and cerebral fractional tissue oxygen extraction (cFTOE) calculated for the following 3 time intervals: 3-6, 6-12, and 12-28 h of age. Functional ultrasound measures including superior vena cava flow, right ventricular output, ductus arteriosus size and shunt and anterior cerebral artery resistive index were determined., Results: The mean (±SD) gestation and birth weight of the 51 study infants were 27 ± 1 weeks and 1,046 ± 241 g respectively. Twenty infants received DCC and 31 received ICC. Baseline demographics were similar between the 2 groups. Comparing DCC and ICC infants, there was no difference in rScO2 or cFTOE at any time point. Three out of 20 infants did not receive DCC due to clinical concerns. A sensitivity analysis revealed that cord clamping ≥30 s was significantly associated with increased rScO2 and decreased cFTOE at all 3 time points after adjusting for gestation., Conclusion: Although DCC was not associated with changes in cerebral oxygenation overall, sensitivity analysis suggested a possible effect of an increased rScO2 and a decreased cFTOE with ≥30 s of DCC., (© 2018 S. Karger AG, Basel.)

The aims of this study were to develop and validate a prediction equation of fat-free mass (FFM) based on bioelectrical impedance analysis (BIA) and anthropometry using air-displacement plethysmography (ADP) as a reference in Asian neonates and to test the applicability of the prediction equations in an independent Western cohort. A total of 173 neonates at birth and 140 at two weeks of age were included. Multiple linear regression analysis was performed to develop the prediction equations in a two-third randomly selected subset and validated on the remaining one-third subset at each time point and in an independent Queensland cohort. FFM measured by ADP was the dependent variable, and anthropometric measures, sex and impedance quotient (L2/R50) were independent variables in the model. Accuracy of prediction equations was assessed using intra-class correlation and Bland-Altman analyses. L2/R50 was the significant predictor of FFM at week two but not at birth. Compared with the model using weight, sex and length, including L2/R50 slightly improved the prediction with a bias of 0·01 kg with 2 sd limits of agreement (LOA) (0·18, -0·20). Prediction explained 88·9 % of variation but not beyond that of anthropometry. Applying these equations to the Queensland cohort provided similar performance at the appropriate age. However, when the Queensland equations were applied to our cohort, the bias increased slightly but with similar LOA. BIA appears to have limited use in predicting FFM in the first few weeks of life compared with simple anthropometry in Asian populations. There is a need for population- and age-appropriate FFM prediction equations.

Objectives: The newborn circulating, cardiac and renal renin-angiotensin systems (RASs) are essential for blood pressure control, and for cardiac and renal development. If cardiac and renal RASs are immature this may contribute to cardiovascular compromise in preterm infants. This study measured mRNA expression of cardiac and renal RAS components in preterm, glucocorticoid (GC) exposed preterm, and term piglets., Methods: Renal and cardiac RAS mRNA levels were measured using real-time polymerase chain reaction (PCR). Genes studied were: (pro)renin receptor, renin, angiotensinogen, angiotensin converting enzyme (ACE), ACE2, angiotensin type 1 receptor (AT1R) and angiotensin type 2 receptor (AT2R)., Results: All the genes studied were expressed in the kidney; neither renin nor AT2R mRNA were detected in the heart. There were no gestational changes in (pro)renin receptor, renin, ACE or AT1R mRNA levels. Right ventricular angiotensinogen mRNA levels in females were lower in preterm animals than at term, and GC exposure increased levels in male piglets. Renal angiotensinogen mRNA levels in female term piglets were lower than females from both preterm groups, and lower than male term piglets. Left ventricular ACE2 mRNA expression was lower in GC treated preterm piglets. Renal AT2R mRNA abundance was highest in GC treated preterm piglets, and the AT1R/AT2R ratio was increased at term., Conclusions: Preterm cardiac and renal RAS mRNA levels were similar to term piglets, suggesting that immaturity of these RASs does not contribute to preterm cardiovascular compromise. Since preterm expression of both renal and cardiac angiotensin II-AT1R is similar to term animals, cardiovascular dysfunction in the sick preterm human neonate might be effectively treated by agents acting on their RASs., (© The Author(s), 2015.)

Background: Obesity is increasing in the child-bearing population as are the rates of gestational diabetes. Gestational diabetes is associated with higher rates of Cesarean Section for the mother and increased risks of macrosomia, higher body fat mass, respiratory distress and hypoglycemia for the infant. Prevention of gestational diabetes through life style intervention has proven to be difficult. A Finnish study showed that ingestion of specific probiotics altered the composition of the gut microbiome and thereby metabolism from early gestation and decreased rates of gestational diabetes in normal weight women. In SPRING (the Study of Probiotics IN the prevention of Gestational diabetes), the effectiveness of probiotics ingestion for the prevention of gestational diabetes will be assessed in overweight and obese women., Methods/design: SPRING is a multi-center, prospective, double-blind randomized controlled trial run at two tertiary maternity hospitals in Brisbane, Australia. Five hundred and forty (540) women with a BMI > 25.0 kg/m(2) will be recruited over 2 years and receive either probiotics or placebo capsules from 16 weeks gestation until delivery. The probiotics capsules contain > 1x10(9) cfu each of Lactobacillus rhamnosus GG and Bifidobacterium lactis BB-12 per capsule. The primary outcome is diagnosis of gestational diabetes at 28 weeks gestation. Secondary outcomes include rates of other pregnancy complications, gestational weight gain, mode of delivery, change in gut microbiome, preterm birth, macrosomia, and infant body composition. The trial has 80% power at a 5% 2-sided significance level to detect a >50% change in the rates of gestational diabetes in this high-risk group of pregnant women., Discussion: SPRING will show if probiotics can be used as an easily implementable method of preventing gestational diabetes in the high-risk group of overweight and obese pregnant women.

Objective: Changes in cerebral impedance in the newborn piglet are able to discriminate, within 1-2 h of acute hypoxia, between animals which will have a good neurological outcome, and those who have suffered more severe hypoxia resulting in poor outcome. The aim of this study was to determine if cerebral impedance could be used to identify those human infants with an encephalopathy following acute hypoxia who subsequently have a poor neurological outcome. It is these infants who may benefit most from neural rescue treatment., Methods: Twenty-four newborn term infants with evidence of severe acute intrapartum hypoxia and encephalopathy were studied. Bioimpedance spectroscopy was commenced as soon as possible after birth and repeated every 30 min until the infant was 12 h old. Neurodevelopmental outcome was assessed at 12 months of age., Results: Although cerebral impedance was different to control values, there was no significant difference in cerebral impedance between hypoxic babies with normal and those with abnormal development., Conclusion: Cerebral impedance was increased in hypoxic babies, as predicted from animal data, but the method was not suitable for discrimination of outcome., Significance: Cerebral impedance is not useful for early identification of infants who subsequently have a poor outcome after acute intrapartum hypoxia and who may benefit from neural rescue treatment.

Bioelectrical impedance analysis may be useful for cot-side monitoring of fluid balance in the neonatal intensive care unit (NICU). However the presence of cardio-respiratory monitoring equipment, non-ideal electrode placement and inability to obtain accurate crown-heel measurements may interfere with the ability to obtain reliable impedance data in this setting. This study aimed to investigate the effects of these factors on impedance analysis and to develop a prediction equation for extracellular fluid volume in the neonate. The study found that cardio respiratory monitoring had no significant effect on multi-frequency impedance measurements. Placement of current delivering electrodes on the ventral rather than dorsal surfaces improved separation of current and voltage electrodes but did not alter impedance results. Contralateral measurements were not significantly different to ipsilateral measurements. In 24 infants, extracellular fluid volume was measured using corrected bromide space (CBS) and simultaneous impedance analysis was performed. There was good correlation between CBS and the impedance quotient FF2/Ro where F is foot length and R0 is resistance at zero frequency. The study concludes that despite many potential difficulties associated with impedance analysis in the NICU, reliable measurements of impedance can be obtained and further work to validate prediction equations for ECF is warranted.

The passive permeability to 36Cl of isolated pieces of amnion (112), amniochorion (41) and allantois (54) from 55 pregnant ewes was studied in vitro. There was a significant decrease in the permeability coefficient (K) with increasing age in both amnion and allantois when samples from two age groups (72 to 109; 110 to 147 days of gestation) were analysed. There was a highly significant correlation (P less than 0.001) between amnion permeability and amniotic fluid [Cl-], but none between allantoic permeability and allantoic fluid [Cl-]. Amniotic fluid osmolality decreased significantly over the last third of gestation and was significantly correlated with amniotic fluid [Cl-]. Allantoic fluid osmolality increased with age and did not correlate with allantoic fluid [Cl-]. The anion exchange blocker, SITS, significantly decreased K in the amnion in the younger age group, suggesting that anion exchange through cell membranes may be one route of Cl- movement through the young amnion. The results suggest that the permeability of the amnion may play a role in the regulation of the composition of amniotic but not allantoic fluid in sheep.

Serial measurements of amniotic fluid volume were made using a tracer dilution technique in sheep during the last half of gestation. No consistent trends were observed in amniotic fluid volume changes over this period. Disappearance of tracer-labeled urea and water from the amniotic fluid was observed at various gestational ages during the last half of pregnancy. The rate of disappearance of urea from the amniotic fluid decreased with gestational age. The disappearance rate of water did not change. Relationships between disappearance rates and amniotic fluid volume suggest that the permeability of the fetal membranes may be important in determining amniotic fluid volume.

Twenty to thirty percent of amniotic fluid volume was replaced by isotonic solutions of saline, mannitol, or dextrose in chronically cannulated ovine fetuses. In all cases the sodium, potassium, and chloride concentrations returned to control values in 3 to 6 hours. Urea and creatinine behaved similarly in the saline and mannitol experiments, but rose above control values within 1 hour of dextrose replacement. Amniotic fluid volume increased with return of solute. Fetal urine drainage to the exterior abolished the rapid return of urea and creatinine concentrations in the dextrose experiments, although no changes in renal function occurred in any experiments. It was concluded that dextrose inhibited the exit of urea and creatinine from the amniotic compartment.

The fetuses of nine pregnant ewes were chronically cannulated between 86 and 130 days with cannulae in one carotid artery, one jugular vein, the fetal bladder and the amniotic cavity. The effects of infused AVP on fetal urine flow rate and composition were studied. A dose of 35 pmol. h-1 always caused an increase in urine osmolality and a decrease in flow rate and free water clearance without change in blood pressure. Higher doses (140 pmol.h-1) were significantly pressor and caused increased excretion of sodium, chloride, urea and creatinine. Although this dose always caused an increase in urine osmolality, in five experiments the flow rate also rose. It is concluded that the ovine fetus has the ability to control its own urine flow and composition, and possibly also amniotic fluid volume and composition.

Permeability of ovine amnion and amniochorion to urea and water was measured in vitro at various gestational ages. Permeability of amniochorion was between 30 and 100% of that of amnion. Permeability of the membranes to water did not change with fetal age, whereas permeability of amnion to urea decreased from 1.548 +/- 0.541 (49) 10(-4) cm . sec-1 to 0.277 +/- 0.339 (102) 10(-4) cm . sec-1 as fetal age increased. There was a significant relationship between the permeability of the amnion to urea and the concentration of urea in the amniotic fluid. It was concluded that the decrease in membrane permeability to urea may be responsible in part for the increase in amniotic fluid urea concentration observed as gestation progresses.