Antenatal corticosteroids for fetal lung maturation in threatened preterm delivery: indications and administration

Antenatal maternal administration of corticosteroids has been shown to reduce morbidity and mortality rates in preterm delivery. Threatened spontaneous or medically indicated preterm delivery for maternal or fetal indications between 24 and 34 weeks of gestation with unknown fetal lung maturity status are indications for antenatal corticosteroid administration. Recent studies have challenged current practice of antenatal glucocorticoid use. The goal of this expert letter is to provide recommendations based for the clinical use of antenatal glucocorticoids based on the current evidence from published studies.

Prevention of preterm delivery with vaginal progesterone in women with preterm labour (4P): randomised double-blind placebo-controlled trial.

OBJECTIVE To evaluate the effectiveness of 200 mg of daily vaginal natural progesterone to prevent preterm birth in women with preterm labour. DESIGN Multicentre, randomised, double-blind, placebo-controlled trial. SETTING Twenty-nine centres in Switzerland and Argentina. POPULATION A total of 385 women with preterm labour (24(0/7) to 33(6/7) weeks of gestation) treated with acute tocolysis. METHODS Participants were randomly allocated to either 200 mg daily of self-administered vaginal progesterone or placebo within 48 hours of starting acute tocolysis. MAIN OUTCOME MEASURES Primary outcome was delivery before 37 weeks of gestation. Secondary outcomes were delivery before 32 and 34 weeks, adverse effects, duration of tocolysis, re-admissions for preterm labour, length of hospital stay, and neonatal morbidity and mortality. The study was ended prematurely based on results of the intermediate analysis. RESULTS Preterm birth occurred in 42.5% of women in the progesterone group versus 35.5% in the placebo group (relative risk [RR] 1.2; 95% confidence interval [95% CI] 0.93-1.5). Delivery at <32 and <34 weeks did not differ between the two groups (12.9 versus 9.7%; [RR 1.3; 95% CI 0.7-2.5] and 19.7 versus 12.9% [RR 1.5; 95% CI 0.9-2.4], respectively). The duration of tocolysis, hospitalisation, and recurrence of preterm labour were comparable between groups. Neonatal morbidity occurred in 44 (22.8%) cases on progesterone versus 35 (18.8%) cases on placebo (RR: 1.2; 95% CI 0.82-1.8), whereas there were 4 (2%) neonatal deaths in each study group. CONCLUSION There is no evidence that the daily administration of 200 mg vaginal progesterone decreases preterm birth or improves neonatal outcome in women with preterm labour.

Cholesterol acceptor capacity is preserved by different mechanisms in preterm and term fetuses.

Fetal serum cholesterol and lipoprotein concentrations differ between preterm and term born neonates. An imbalance of the flow of cholesterol from the sites of synthesis or efflux from cells of peripheral organs to the liver, the reverse cholesterol transport (RCT), is linked to atherosclerosis and cardiovascular disease (CVD). Preterm delivery is a risk factor for the development of CVD. Thus, we hypothesized that RCT is affected by a diminished cholesterol acceptor capacity in preterm as compared to term fetuses. Cholesterol efflux assays were performed in RAW264.7, HepG2, and HUVEC cell lines. In the presence and absence of ABC transporter overexpression by TO-901317, umbilical cord sera of preterm and term born neonates (n = 28 in both groups) were added. Lipid components including high density lipoprotein (HDL), low density lipoprotein (LDL), apolipoprotein A1, and apolipoprotein E were measured and related to fractional cholesterol efflux values. We found overall, fractional cholesterol efflux to remain constant between the study groups, and over gestational ages at delivery, respectively. However, correlation analysis revealed cholesterol efflux values to be predominantly related to HDL concentration at term, while in preterm neonates, cholesterol efflux was mainly associated with LDL In conclusion cholesterol acceptor capacity during fetal development is kept in a steady state with different mechanisms and lipid fractions involved at distinct stages during the second half of fetal development. However, RCT mechanisms in preterm neonates seem not to be involved in the development of CVD later in life suggesting rather changes in the lipoprotein pattern causative.

Perinatal care at the limit of viability between 22 and 26 completed weeks of gestation in Switzerland. 2011 revision of the Swiss recommendations

Perinatal care of pregnant women at high risk for preterm delivery and of preterm infants born at the limit of viability (22-26 completed weeks of gestation) requires a multidisciplinary approach by an experienced perinatal team. Limited precision in the determination of both gestational age and foetal weight, as well as biological variability may significantly affect the course of action chosen in individual cases. The decisions that must be taken with the pregnant women and on behalf of the preterm infant in this context are complex and have far-reaching consequences. When counselling pregnant women and their partners, neonatologists and obstetricians should provide them with comprehensive information in a sensitive and supportive way to build a basis of trust. The decisions are developed in a continuing dialogue between all parties involved (physicians, midwives, nursing staff and parents) with the principal aim to find solutions that are in the infant's and pregnant woman's best interest. Knowledge of current gestational age-specific mortality and morbidity rates and how they are modified by prenatally known prognostic factors (estimated foetal weight, sex, exposure or nonexposure to antenatal corticosteroids, single or multiple births) as well as the application of accepted ethical principles form the basis for responsible decision-making. Communication between all parties involved plays a central role. The members of the interdisciplinary working group suggest that the care of preterm infants with a gestational age between 22 0/7 and 23 6/7 weeks should generally be limited to palliative care. Obstetric interventions for foetal indications such as Caesarean section delivery are usually not indicated. In selected cases, for example, after 23 weeks of pregnancy have been completed and several of the above mentioned prenatally known prognostic factors are favourable or well informed parents insist on the initiation of life-sustaining therapies, active obstetric interventions for foetal indications and provisional intensive care of the neonate may be reasonable. In preterm infants with a gestational age between 24 0/7 and 24 6/7 weeks, it can be difficult to determine whether the burden of obstetric interventions and neonatal intensive care is justified given the limited chances of success of such a therapy. In such cases, the individual constellation of prenatally known factors which impact on prognosis can be helpful in the decision making process with the parents. In preterm infants with a gestational age between 25 0/7 and 25 6/7 weeks, foetal surveillance, obstetric interventions for foetal indications and neonatal intensive care measures are generally indicated. However, if several prenatally known prognostic factors are unfavourable and the parents agree, primary non-intervention and neonatal palliative care can be considered. All pregnant women with threatening preterm delivery or premature rupture of membranes at the limit of viability must be transferred to a perinatal centre with a level III neonatal intensive care unit no later than 23 0/7 weeks of gestation, unless emergency delivery is indicated. An experienced neonatology team should be involved in all deliveries that take place after 23 0/7 weeks of gestation to help to decide together with the parents if the initiation of intensive care measures appears to be appropriate or if preference should be given to palliative care (i.e., primary non-intervention). In doubtful situations, it can be reasonable to initiate intensive care and to admit the preterm infant to a neonatal intensive care unit (i.e., provisional intensive care). The infant's clinical evolution and additional discussions with the parents will help to clarify whether the life-sustaining therapies should be continued or withdrawn. Life support is continued as long as there is reasonable hope for survival and the infant's burden of intensive care is acceptable. If, on the other hand, the health car...

Fetal thymic involution: a sonographic marker of the fetal inflammatory response syndrome

OBJECTIVE: The purpose of this study was to evaluate whether there is a relationship between the sonographic fetal thymus size and the presence of an intrauterine infection in patients with preterm labor. STUDY DESIGN: Thirty-one women who had been admitted with preterm labor and intact membranes between 24 and 32 weeks of gestation were included. Fetal thymus perimeter was measured sonographically, and amniocentesis for the microbiologic assessment of the amniotic cavity was performed. Placentas and umbilical cords were examined for the presence of chorioamnionitis/funisitis. RESULTS: The prevalence of preterm delivery and intra-amniotic infection was 51.6% (16/31 women) and 32.3% (10/31 women), respectively. In all cases with intrauterine infection and in 23.8% of cases without intrauterine infection, the fetal thymus perimeter was below the 5th percentile for gestational age (10/10 women vs 5/21 women; P < .01). Isolated histologic chorioamnionitis and funisitis were found in 22.6% and 25.8% of fetuses, respectively. The fetal thymus was below the 5th percentile for gestational age in 100%, 71.4%, and 12.5% of patients with histologic signs of funisitis and isolated chorioamnionitis and without histologic signs of infection, respectively. CONCLUSION: Fetal thymus involution in preterm labor patients is strongly associated with funisitis, which is the histologic manifestation of the fetal inflammatory response syndrome.

[Pre-eclampsia and its psychosocial sequelae]

In the present work some psychosomatic conditions in the setting of preeclampsia are described. The important psychosocial consequences for women suffering from this disease and the drawback for their partners will be elucidated. Preeclampsia as a disease including hypertension, proteinuria and generalized edema is often associted with generalized seizures occuring most commonly at the end of the second trimenon of pregnancy. The disease bears a heavy risk for the mothers as well as for her unborn child. Until now the exact pathophysiological basis of the disease has not been entirely elucidated. For the pregnant woman and her psychosocial surrounding the outbreak of the disease is in most cases unexpected. During development of the disease she has to face a role change from a so far normal pregnancy to a high-risk situation. This may change also the attitude to the unborn child by herself and her partner. The preterm delivery induced therapeutically, together with the succeeding problems for the newborn complete the high psychosocial stress related to the entire situation. Therefore it is useful and important to offer psychosocial support to the mother as well as to her parter during the illness and the time after delivery.

Analysis of caesarean section rates over time in a single Swiss centre using a ten-group classification system.

OBJECTIVE Caesarean section (CS) rates have risen over the past two decades. The aim of this observational study was to identify time-dependent variations in CS and vaginal delivery rates over a period of 11 years. METHOD All deliveries (13,701 deliveries during the period 1999-2009) at the University Women's Hospital Bern were analysed using an internationally standardised and approved ten-group classification system. Caesarean sections on maternal request (CSMR) were evaluated separately. RESULTS We detected an overall CS rate of 36.63% and an increase in the CS rate over time (p <0.001). Low-risk profile groups were the two largest populations and displayed low CS rates, with significantly decreasing relative size over time. The relative size of groups with induced labour increased significantly, but this did not have an impact on the overall CS rate. Pregnancies complicated by breech position, multiple pregnancies and abnormal lies did not have an impact on overall CS rate. The biggest contributor to a high CS rate was preterm delivery and the existence of a uterine scar from a previous CS. CSMR was 1.45% and did not have an impact on the overall CS rate. CONCLUSION The observational study identified wide variations in caesarean section and vaginal delivery rates across the groups over time, and a shift towards high-risk populations was noted. The biggest contributors to high CS rates were identified; namely, previous uterine scar and preterm delivery. Interventions aiming to reduce CS rates are planned.

Gene expression profile in newborn rat lungs after two days of recovery of mechanical ventilation.

BACKGROUND Preterm infants having immature lungs often require respiratory support, potentially leading to bronchopulmonary dysplasia (BPD). Conventional BPD rodent models based on mechanical ventilation (MV) present outcome measured at the end of the ventilation period. A reversible intubation and ventilation model in newborn rats recently allowed discovering that different sets of genes modified their expression related to time after MV. In a newborn rat model, the expression profile 48 h after MV was analyzed with gene arrays to detect potentially interesting candidates with an impact on BPD development. METHODS Rat pups were injected P4-5 with 2 mg/kg lipopolysaccharide (LPS). One day later, MV with 21 or 60% oxygen was applied during 6 h. Animals were sacrified 48 h after end of ventilation. Affymetrix gene arrays assessed the total gene expression profile in lung tissue. RESULTS In fully treated animals (LPS + MV + 60% O(2)) vs. controls, 271 genes changed expression significantly. All modified genes could be classified in six pathways: tissue remodeling/wound repair, immune system and inflammatory response, hematopoiesis, vasodilatation, and oxidative stress. Major alterations were found in the MMP and complement system. CONCLUSION MMPs and complement factors play a central role in several of the pathways identified and may represent interesting targets for BPD treatment/prevention.Bronchopulmonary dysplasia (BPD) is a chronic lung disease occurring in ~30% of preterm infants born less than 30 wk of gestation (1). Its main risk factors include lung immaturity due to preterm delivery, mechanical ventilation (MV), oxygen toxicity, chorioamnionitis, and sepsis. The main feature is an arrest of alveolar and capillary formation (2). Models trying to decipher genes involved in the pathophysiology of BPD are mainly based on MV and oxygen application to young mammals with immature lungs of different species (3). In newborn rodent models, analyses of lung structure and gene and protein expression are performed for practical reasons directly at the end of MV (4,5,6). However, later appearing changes of gene expression might also have an impact on lung development and the evolution towards BPD and cannot be discovered by such models. Recently, we developed a newborn rat model of MV using an atraumatic (orotracheal) intubation technique that allows the weaning of the newborn animal off anesthesia and MV, the extubation to spontaneous breathing, and therefore allows the evaluation of effects of MV after a ventilation-free period of recovery (7). Indeed, applying this concept of atraumatic intubation by direct laryngoscopy, we recently were able to show significant differences between gene expression changes appearing directly after MV compared to those measured after a ventilation-free interval of 48 h. Immediately after MV, inflammation-related genes showed a transitory modified expression, while another set of more structurally related genes changed their expression only after a delay of 2 d (7). Lung structure, analyzed by conventional 2D histology and also by 3D reconstruction using synchrotron x-ray tomographic microscopy revealed, 48 h after end of MV, a reduced complexity of lung architecture compared to the nonventilated rat lungs, similar to the typical findings in BPD. To extend these observations about late gene expression modifications, we performed with a similar model a full gene expression profile of lung tissue 48 h after the end of MV with either room air or 60% oxygen. Essentially, we measured changes in the expression of genes related to the MMPs and complement system which played a role in many of the six identified mostly affected pathways.

A multinational case-control study on childhood brain tumours, anthropogenic factors, birth characteristics and prenatal exposures: A validation of interview data.

Little is known about the aetiology of childhood brain tumours. We investigated anthropometric factors (birth weight, length, maternal age), birth characteristics (e.g. vacuum extraction, preterm delivery, birth order) and exposures during pregnancy (e.g. maternal: smoking, working, dietary supplement intake) in relation to risk of brain tumour diagnosis among 7-19 year olds. The multinational case-control study in Denmark, Sweden, Norway and Switzerland (CEFALO) included interviews with 352 (participation rate=83.2%) eligible cases and 646 (71.1%) population-based controls. Interview data were complemented with data from birth registries and validated by assessing agreement (Cohen's Kappa). We used conditional logistic regression models matched on age, sex and geographical region (adjusted for maternal age and parental education) to explore associations between birth factors and childhood brain tumour risk. Agreement between interview and birth registry data ranged from moderate (Kappa=0.54; worked during pregnancy) to almost perfect (Kappa=0.98; birth weight). Neither anthropogenic factors nor birth characteristics were associated with childhood brain tumour risk. Maternal vitamin intake during pregnancy was indicative of a protective effect (OR 0.75, 95%-CI: 0.56-1.01). No association was seen for maternal smoking during pregnancy or working during pregnancy. We found little evidence that the considered birth factors were related to brain tumour risk among children and adolescents.

Maturation of endogenous glucose production in preterm and term calves

Glucose disposability is often impaired in neonatal calves and even more in preterm calves. The objective of this study was to investigate ontogenic maturation of endogenous glucose production (eGP) in calves and its effects on postnatal glucose homeostasis. Calves (n = 7 per group) were born preterm (PT; delivered by section 9 d before term) or at term (T; spontaneous vaginal delivery), or spontaneously born and fed colostrum for 4 d (TC). Blood samples were taken immediately after birth and before and 2h after feeding at 24h after birth (PT; T) or on d 4 of life (TC) to determine metabolic and endocrine changes. After birth (PT and T) or on d 3 of life (TC), fasted calves were gavaged with deuterium-labeled water to determine gluconeogenesis (GNG) and intravenously infused with [U(13)C]-glucose to measure eGP and glucose oxidation (GOx) in blood plasma. After slaughter at 26h after birth (PT, T) or on d 4 of life (TC), glycogen concentrations in liver and hepatic mRNA concentrations and enzyme activities of pyruvate carboxylase, phosphoenolpyruvate carboxykinase (PEPCK), and glucose-6-phosphatase were measured. Preterm calves had the lowest plasma concentrations of cortisol and 3,5,3'-triiodothyronine at birth. Plasma glucose concentrations from d 1 to 2 decreased more, but plasma concentrations of lactate and urea and glucagon:insulin ratio were higher in PT than in T and TC calves. The eGP, GNG, GOx, as well as hepatic glycogen concentrations and PEPCK activities, were lowest in PT calves. Results indicate impaired glucose homeostasis due to decreased eGP in PT calves and maturation of eGP with ontogenic development.

Stem Cells From Umbilical Cord Wharton's Jelly From Preterm Birth Have Neuroglial Differentiation Potential

Objective:The aim of the study is to determine the neuroglial differentiation potential of human Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) from preterm birth when compared to term delivery.Study Design:The WJ-MSCs from umbilical cords of preterm birth and term controls were isolated and induced into neural progenitors. The cells were analyzed for neuroglial markers by flow cytometry, real-time polymerase chain reaction, and immunocytochemistry. Results:Independent of gestational age, a subset of WJ-MSC displayed the neural progenitor cell markers Nestin and Musashi-1 and the mature neural markers microtubule-associated protein 2, glial fibrillary acidic protein, and myelin basic protein. Neuroglial induction of WJ-MSCs from term and preterm birth resulted in the enhanced transcription of Nestin and Musashi-1.Conclusions:Undifferentiated WJ-MSCs from preterm birth express neuroglial markers and can be successfully induced into neural progenitors similar to term controls. Their potential use as cellular graft in neuroregenerative therapy for peripartum brain injury in preterm birth has to be tested.

Development of the premature infant nose throat-model (PrINT-Model): an upper airway replica of a premature neonate for the study of aerosol delivery

Clinical efficacy of aerosol therapy in premature newborns depends on the efficiency of delivery of aerosolized drug to the bronchial tree. To study the influence of various anatomical, physical, and physiological factors on aerosol delivery in preterm newborns, it is crucial to have appropriate in vitro models, which are currently not available. We therefore constructed the premature infant nose throat-model (PrINT-Model), an upper airway model corresponding to a premature infant of 32-wk gestational age by three-dimensional (3D) reconstruction of a three-planar magnetic resonance imaging scan and subsequent 3D-printing. Validation was realized by visual comparison and comparison of total airway volume. To study the feasibility of measuring aerosol deposition, budesonide was aerosolized through the cast and lung dose was expressed as percentage of nominal dose. The airway volumes of the initial magnetic resonance imaging and validation computed tomography scan showed a relative deviation of 0.94%. Lung dose at low flow (1 L/min) was 61.84% and 9.00% at high flow (10 L/min), p < 0.0001. 3D-reconstruction provided an anatomically accurate surrogate of the upper airways of a 32-wk-old premature infant, making the model suitable for future in vitro testing.

Neonatal procedural pain exposure and pain management in ventilated preterm infants during the first 14 days of life

OBJECTIVES: Ventilated preterm infants are at high risk for procedural pain exposure. In Switzerland there is a lack of knowledge about the pain management in this highly vulnerable patient population. The aims of this study were to describe the type and frequency of procedures and to determine the amount of analgesia given to this patient group in two Swiss neonatal intensive care units. METHOD: A retrospective cohort study was performed examining procedural exposure and pain management of a convenience sample of 120 ventilated preterm infants (mean age = 29.7 weeks of gestation) during the first 14 days of life after delivery and born between May 1st 2004 and March 31st 2006. RESULTS: The total number of procedures all the infants underwent was 38,626 indicating a mean of 22.9 general procedures performed per child and day. Overall, 75.6% of these procedures are considered to be painful. The most frequently performed procedure is manipulation on the CPAP prongs. Pain measurements were performed four to seven times per day. In all, 99.2% of the infants received either non-pharmacological and/or pharmacological agents and 70.8% received orally administered glucose as pre-emptive analgesia. Morphine was the most commonly used pharmacological agent. DISCUSSION: The number of procedures ventilated preterm infants are exposed to is disconcerting. Iatrogenic pain is a serious problem, particularly in preterm infants of low gestational age. The fact that nurses assessed pain on average four to seven times daily per infant indicates a commitment to exploring a painful state in a highly vulnerable patient population. In general, pharmacological pain management and the administration of oral glucose as a non-pharmacological pain relieving intervention appear to be adequate, but there may be deficiencies, particularly for extremely low birth weight infants born <28 weeks of gestation.

Factors influencing the accuracy of fetal weight estimation with a focus on preterm birth at the limit of viability: a systematic literature review

BACKGROUND Fetal weight estimation (FWE) is an important factor for clinical management decisions, especially in imminent preterm birth at the limit of viability between 23(0/7) and 26(0/7) weeks of gestation. It is crucial to detect and eliminate factors that have a negative impact on the accuracy of FWE. DATA SOURCES In this systematic literature review, we investigated 14 factors that may influence the accuracy of FWE, in particular in preterm neonates born at the limit of viability. RESULTS We found that gestational age, maternal body mass index, amniotic fluid index and ruptured membranes, presentation of the fetus, location of the placenta and the presence of multiple fetuses do not seem to have an impact on FWE accuracy. The influence of the examiner's grade of experience and that of fetal gender were discussed controversially. Fetal weight, time interval between estimation and delivery and the use of different formulas seem to have an evident effect on FWE accuracy. No results were obtained on the impact of active labor. DISCUSSION This review reveals that only few studies investigated factors possibly influencing the accuracy of FWE in preterm neonates at the limit of viability. Further research in this specific age group on potential confounding factors is needed.