Perinatal risk factors for adverse neurodevelopmental outcome after spontaneous preterm birth

Altered Functional Brain Network Integration, Segregation, and Modularity in Infants Born Very Preterm at Term-Equivalent Age

OBJECTIVES

To determine the functional network organization of the brain in infants born very preterm at term-equivalent age and to relate network alterations to known clinical risk factors for poor neurologic outcomes in prematurity.

STUDY DESIGN

Resting-state functional magnetic resonance imaging data from 66 infants born very preterm (gestational age <32 weeks and birth weight <1500 g) and 66 healthy neonates born at full term, acquired as part of a prospective, cross-sectional study, were compared at term age using graph theory. Features of resting-state networks, including integration, segregation, and modularity, were derived from correlated hemodynamic activity arising from 93 cortical and subcortical regions of interest and compared between groups.

RESULTS

Despite preserved small-world topology and modular organization, resting-state networks of infants born very preterm at term-equivalent age were less segregated and less integrated than those of infants born full term. Chronic respiratory illness (ie, bronchopulmonary dysplasia and the length of oxygen support) was associated with decreased global efficiency and increased path lengths (P < .05). In both cohorts, 4 functional modules with similar composition were observed (parietal/temporal, frontal, subcortical/limbic, and occipital). The density of connections in 3 of the 4 modules was decreased in the very preterm network (P < .01); however, in the occipital/visual cortex module, connectivity was increased in infants born very preterm relative to control infants (P < .0001).

CONCLUSIONS

Early exposure to the ex utero environment is associated with altered resting-state network functional organization in infants born very preterm at term-equivalent age, likely reflecting disrupted brain maturational processes.

Developing routinely recorded clinical data from electronic patient records as a national resource to improve neonatal health care: the Medicines for Neonates research programme

Background

Clinical data offer the potential to advance patient care. Neonatal specialised care is a high-cost NHS service received by approximately 80,000 newborn infants each year.

Objectives

(1) To develop the use of routinely recorded operational clinical data from electronic patient records (EPRs), secure national coverage, evaluate and improve the quality of clinical data, and develop their use as a national resource to improve neonatal health care and outcomes. To test the hypotheses that (2) clinical and research data are of comparable quality, (3) routine NHS clinical assessment at the age of 2 years reliably identifies children with neurodevelopmental impairment and (4) trial-based economic evaluations of neonatal interventions can be reliably conducted using clinical data. (5) To test methods to link NHS data sets and (6) to evaluate parent views of personal data in research.

Design

Six inter-related workstreams; quarterly extractions of predefined data from neonatal EPRs; and approvals from the National Research Ethics Service, Health Research Authority Confidentiality Advisory Group, Caldicott Guardians and lead neonatal clinicians of participating NHS trusts.

Setting

NHS neonatal units.

Participants

Neonatal clinical teams; parents of babies admitted to NHS neonatal units.

Interventions

In workstream 3, we employed the Bayley-III scales to evaluate neurodevelopmental status and the Quantitative Checklist of Autism in Toddlers (Q-CHAT) to evaluate social communication skills. In workstream 6, we recruited parents with previous experience of a child in neonatal care to assist in the design of a questionnaire directed at the parents of infants admitted to neonatal units.

Data sources

Data were extracted from the EPR of admissions to NHS neonatal units.

Main outcome measures

We created a National Neonatal Research Database (NNRD) containing a defined extract from real-time, point-of-care, clinician-entered EPRs from all NHS neonatal units in England, Wales and Scotland (n = 200), established a UK Neonatal Collaborative of all NHS trusts providing neonatal specialised care, and created a new NHS information standard: the Neonatal Data Set (ISB 1595) (see http://webarchive.nationalarchives.gov.uk/±/http://www.isb.nhs.uk/documents/isb-1595/amd-32–2012/index_html; accessed 25 June 2018).

Results

We found low discordance between clinical (NNRD) and research data for most important infant and maternal characteristics, and higher prevalence of clinical outcomes. Compared with research assessments, NHS clinical assessment at the age of 2 years has lower sensitivity but higher specificity for identifying children with neurodevelopmental impairment. Completeness and quality are higher for clinical than for administrative NHS data; linkage is feasible and substantially enhances data quality and scope. The majority of hospital resource inputs for economic evaluations of neonatal interventions can be extracted reliably from the NNRD. In general, there is strong parent support for sharing routine clinical data for research purposes.

Limitations

We were only able to include data from all English neonatal units from 2012 onwards and conduct only limited cross validation of NNRD data directly against data in paper case notes. We were unable to conduct qualitative analyses of parent perspectives. We were also only able to assess the utility of trial-based economic evaluations of neonatal interventions using a single trial. We suggest that results should be validated against other trials.

Conclusions

We show that it is possible to obtain research-standard data from neonatal EPRs, and achieve complete population coverage, but we highlight the importance of implementing systematic examination of NHS data quality and completeness and testing methods to improve these measures. Currently available EPR data do not enable ascertainment of neurodevelopmental outcomes reliably in very preterm infants. Measures to maintain high quality and completeness of clinical and administrative data are important health service goals. As parent support for sharing clinical data for research is underpinned by strong altruistic motivation, improving wider public understanding of benefits may enhance informed decision-making.

Future work

We aim to implement a new paradigm for newborn health care in which continuous incremental improvement is achieved efficiently and cost-effectively by close integration of evidence generation with clinical care through the use of high-quality EPR data. In future work, we aim to automate completeness and quality checks and make recording processes more ‘user friendly’ and constructed in ways that minimise the likelihood of missing or erroneous entries. The development of criteria that provide assurance that data conform to prespecified completeness and quality criteria would be an important development. The benefits of EPR data might be extended by testing their use in large pragmatic clinical trials. It would also be of value to develop methods to quality assure EPR data including involving parents, and link the NNRD to other health, social care and educational data sets to facilitate the acquisition of lifelong outcomes across multiple domains.

Study registration

This study is registered as PROSPERO CRD42015017439 (workstream 1) and PROSPERO CRD42012002168 (workstream 3).

Funding

The National Institute for Health Research Programme Grants for Applied Research programme (£1,641,471). Unrestricted donations were supplied by Abbott Laboratories (Maidenhead, UK: £35,000), Nutricia Research Foundation (Schiphol, the Netherlands: £15,000), GE Healthcare (Amersham, UK: £1000). A grant to support the use of routinely collected, standardised, electronic clinical data for audit, management and multidisciplinary feedback in neonatal medicine was received from the Department of Health and Social Care (£135,494).

Prenatal Risk Factors for Adverse Developmental Outcome in Preterm Infants-Systematic Review

Background: Preterm infants are still at an increased risk for suboptimal neurodevelopmental outcomes when compared with term born infants. The development of a child born preterm can be jeopardized by suboptimal conditions during pregnancy, in addition to the suboptimal growth environment postnatally compared to the normal in utero environment. This review summarizes the literature on the role of chorioamnionitis, placental insufficiency, and maternal smoking on the developmental outcomes of preterm infants. Methods: A systematic database search was performed to identify all original articles published on or before September 12, 2018 that evaluated the impact of clinical or histological chorioamnionitis, abnormal prenatal fetal and placental blood flow, and prenatal smoking exposure on the neuropsychological and cognitive outcomes of preterm infants. We identified a total of 54 studies. Thirty five original articles evaluated the effects of clinical or histological chorioamnionitis; 15 studies evaluated the effects of abnormal blood flow patterns; and four studies evaluated the effects of maternal smoking during pregnancy. Results: The studies on prenatal risk factors showed conflicting results about the impact on the neurodevelopment of preterm infants. The majority of the studies did not show that chorioamnionitis poses a direct risk to the development of preterm infants. The role of abnormal prenatal placental and fetal blood flow on the development of preterm infants remained inconclusive because the sample sizes were often small and methodological problems complicated the interpretation of the data. Maternal smoking during pregnancy was assessed only in one cohort which showed that maternal smoking is a risk for suboptimal cognitive and neuropsychological development in preterm infants. Conclusions: This review summarizes the data on several prenatal risk factors which play a role in the developmental outcomes of preterm infants. To optimize the developmental outcomes, we need to first optimize the fetal wellbeing before birth. More research that extends from the fetal life to long-term developmental outcomes is needed.

Neonatal outcome in preterm deliveries before 34-week gestation - the influence of the mechanism of labor onset

Purpose: To evaluate neonatal outcomes in preterm infants with less than 34 weeks after spontaneous labor, preterm premature rupture of membranes (PPROM) or iatrogenic delivery and to clarify whether the mechanism of labor onset is a risk factor for adverse short-term neonatal outcome. Methods: We performed a retrospective case-control study, which included 266 preterm newborns with less than 34-week gestation, between 2011 and 2015. Neonatal outcomes were compared according to the mechanism of labor onset. Our primary outcomes were neonatal death, sequelae on hospital discharge and a composite of these two variables (combined neonatal outcome). Results: Compared to spontaneous preterm labor, iatrogenic preterm newborns were at increased risk of respiratory distress syndrome (RDS) [Odds Ratio (OR) 3.05 (95%CI 1.31; 7.12)], and need of exogenous surfactant administration [OR 3.87 (95%CI 1.60; 9.35)]. PPROM was associated with higher risk of neonatal sepsis [OR 12.96 (95%CI 1.18; 142.67)]. There were no differences regarding the combined outcome for iatrogenic [OR 0.94 (95%CI 0.33; 2.71)] or PPROM [OR 1.11 (95%CI 0.35; 3.49)] groups. Conclusions: In our study, the different mechanisms of labor onset are associated with different neonatal outcomes. Iatrogenic preterm birth was associated with an increased risk of RDS and a higher need of exogenous surfactant administration than spontaneous group. The rate of neonatal sepsis was significantly higher in PPROM group along with a higher prevalence of histological chorioamnionitis.

Childhood outcomes following preterm prelabor rupture of the membranes (PPROM): a population-based record linkage cohort study

OBJECTIVE

The objective of this study is to determine child health, development and educational outcomes for infants born following preterm prelabor rupture of the membrane (PPROM).

STUDY DESIGN

Population-based record linkage cohort study using data from NSW, Australia, 2001 to 2014.

RESULTS

Of 121 822 births at 20 to 37 weeks, 18 799 (15%) followed PPROM, 56 406 (46%) followed spontaneous labor and 46 617 (38%) were planned. Compared with infants of a similar gestational age born following spontaneous labor or planned delivery, exposure to PPROM did not increase the risk of childhood mortality, childhood hospitalization, developmentally vulnerable at school entry, low reading or numeracy scores. Median latency ranged from 12 days (interquartile range 3 to 37 days) at 25 weeks to 1 day (0 to 2 days) at 36 weeks. Longer latency and more advanced gestational age at birth were associated with better outcomes.

CONCLUSION

Infants born following PPROM are at no greater risk of adverse child health, development and education outcomes than those of similar gestational age born without PPROM.

Continuum of neurobehaviour and its associations with brain MRI in infants born preterm

BACKGROUND

Infants born very preterm (VPT) and moderate-to-late preterm (MLPT) are at increased risk of long-term neurodevelopmental deficits, but how these deficits relate to early neurobehaviour in MLPT children is unclear. The aims of this study were to compare the neurobehavioural performance of infants born across three different gestational age groups: preterm <30 weeks' gestational age (PT<30); MLPT (32-36 weeks' gestational age) and term age (≥37 weeks' gestational age), and explore the relationships between MRI brain abnormalities and neurobehaviour at term-equivalent age.

METHODS

Neurobehaviour was assessed at term-equivalent age in 149 PT<30, 200 MLPT and 200 term-born infants using the Neonatal Intensive Care UnitNetwork Neurobehavioral Scale (NNNS), the Hammersmith Neonatal Neurological Examination (HNNE) and Prechtl's Qualitative Assessment of General Movements (GMA). A subset of 110 PT<30 and 198 MLPT infants had concurrent brain MRI.

RESULTS

Proportions with abnormal neurobehaviour on the NNNS and the HNNE, and abnormal GMA all increased with decreasing gestational age. Higher brain MRI abnormality scores in some regions were associated with suboptimal neurobehaviour on the NNNS and HNNE. The relationships between brain MRI abnormality scores and suboptimal neurobehaviour were similar in both PT<30 and MLPT infants. The relationship between brain MRI abnormality scores and abnormal GMA was stronger in PT<30 infants.

CONCLUSIONS

There was a continuum of neurobehaviour across gestational ages. The relationships between brain abnormality scores and suboptimal neurobehaviour provide evidence that neurobehavioural assessments offer insight into the integrity of the developing brain, and may be useful in earlier identification of the highest-risk infants.

Association of in utero magnesium exposure and spontaneous intestinal perforations in extremely low birth weight infants

OBJECTIVE

The objective of this study is to determine whether antenatal exposure to magnesium is associated with spontaneous intestinal perforation (SIP) in extremely low birth weight (ELBW) infants (⩽1000 g).

STUDY DESIGN

We identified all ELBW infants admitted to 1 of 323 neonatal intensive care units from 2007 to 2013. We used multivariable conditional logistic regression to compare outcomes in the first 21 days after birth between infants exposed and unexposed to magnesium in utero.

RESULTS

Of the 28 035 infants, 11 789 (42%) were exposed to antenatal magnesium (AM). There was no difference in the risk of SIP, odds ratio=1.08 (95% confidence interval; 0.91 to 1.29), between infants exposed and unexposed to AM. Mortality in the first 21 days after birth was lower in the magnesium-exposed infants, odds ratio=0.76 (0.70 to 0.83).

CONCLUSION

AM exposure in ELBW infants was not associated with increased risk of SIP.

Developmental Assessments in Preterm Children: A Meta-analysis

CONTEXT

Developmental outcomes of very preterm (gestational age ≤32 weeks) or very low birth weight (<1500 g) children are commonly reported before age 3 years although the predictive validity for later outcomes are uncertain.

OBJECTIVE

To determine the validity of early developmental assessments in predicting school-age cognitive deficits.

DATA SOURCES

PubMed.

STUDY SELECTION

English-language studies reporting at least 2 serial developmental/cognitive assessments on the same population, 1 between ages 1 and 3 years and 1 at ≥5 years.

DATA EXTRACTION

For each study, we calculated the sensitivity, specificity, and positive and negative predictive values of early assessment for cognitive deficit (defined as test scores 1 SD below the population mean). Pooled meta-analytic sensitivity and specificity were estimated by using a hierarchical summary receiver operator characteristic curve.

RESULTS

We included 24 studies (n = 3133 children). Early assessments were conducted at 18 to 40 months and generally involved the Bayley Scales of Infant Development or the Griffiths Mental Development Scales; 11 different cognitive tests were used at school-age assessments at 5 to 18 years. Positive predictive values ranged from 20.0% to 88.9%, and negative predictive vales ranged from 47.8% to 95.5%. The pooled sensitivity (95% confidence interval) of early assessment for identifying school-age cognitive deficit was 55.0% (45.7%-63.9%) and specificity was 84.1% (77.5%-89.1%). Gestational age, birth weight, age at assessment, and time between assessments did not explain between-study heterogeneity.

LIMITATIONS

The accuracy of aggregated data could not be verified. Many assessment tools have been superseded by newer editions.

CONCLUSIONS

Early developmental assessment has poor sensitivity but good specificity and negative predictive value for school-age cognitive deficit.

Motor and cognitive outcome after specific early lesions of the brain - a systematic review

The aim of this systematic review was to study motor and cognitive outcome in infants with severe early brain lesions and to evaluate effects of side of the lesion, sex, and social economic status on outcome. A literature search was performed using the databases Pubmed and Embase. Included studies involved infants with either cystic periventricular leukomalacia (cPVL), preterm, or term stroke (i.e. parenchymal lesion of the brain). Outcome was expressed as cerebral palsy (CP) and intellectual disability (mental retardation). Median prevalence rates of CP after cPVL, preterm, and term stroke were 86%, 71%, and 29% respectively; of intellectual disability 50%, 27%, and 33%. Most infants with cPVL developed bilateral CP, those with term stroke unilateral CP, whereas after preterm stroke bilateral and unilateral CP occurred equally often. Information on the effects of sex and social economic status on outcome after specific brain lesions was very limited. Our findings show that the risk for CP is high after cPVL, moderate after preterm stroke, and lowest after term stroke. The risk for intellectual disability after an early brain lesion is lower than that for CP. Predicting outcome at individual level remains difficult; new imaging techniques may improve predicting developmental trajectories.

Correlation of serum KL-6 and CC16 levels with neurodevelopmental outcome in premature infants at 12 months corrected age

The aim of this study was to evaluate KL-6 and CC16 levels and their correlation with neurodevelopmental outcome among very low birth weight pre-term infants at 12 months corrected age. This prospective cohort study was performed from 2011 to 2013 by enrolling pre-term neonates of gestational age ≤ 32 weeks and birth weight ≤ 1500 g. Serum KL-6 and CC16 levels were determined 7 days after birth and their correlation with neurodevelopment was evaluated using Gesell Mental Developmental Scales. Of the 86 eligible pre-term infants, 63 completed follow-up, of which 15 had bronchopulmonary dysplasia. At 12 months corrected age, 49 infants had favorable outcomes and 14 infants had poor neurodevelopmental outcome. KL-6 levels were higher and CC16 levels were lower in infants with poor neurodevelopmental outcome compared with those infants who had favourable neurodevelopmental outcome. Serum KL-6 levels less than 90.0 ng/ml and CC16 levels greater than 320.0 pg/ml at 7 days of life were found to be predictive of a favourable outcome at 12 months corrected age. These biological markers could predict neurodevelopmental outcome at 12 months corrected age in very low birth weight premature infants, and help the clinician plan early therapeutic interventions to minimize or avoid poor neurodevelopmental outcome.

Risk factors associated with germinal matrix-intraventricular hemorrhage in preterm neonates

Objective

The purpose of this study is to identify the risk factors associated with the development of germinal matrix-intraventricular hemorrhage (GM-IVH) and the relationship of the severity of disease and prematurity.

Methods

A total of 168 premature neonates whose birth weight ≤1500 g or gestational age ≤34 weeks were examined by cranial ultrasound (CUS) for detection of GM-IVH among the babies admitted between January 2011 and December 2012 in our medical center neonatal intensive care unit. The babies were divided into two groups : GM-IVH and non-IVH. Clinical presentations, precipitating factors of the patients and maternal factors were analyzed.

Results

In univariate analysis, gestational age, birth weight, delivery method, presence of premature rupture of membrane (PROM) and level of sodium and glucose were statistically meaningful factors (p<0.05). But only two factors, gestational age and presence of patent ductus arteriosus (PDA) were statistically meaningful in multivariate logistic regression (p<0.05). Delivery method [normal vaginal delivery (NVD) to Caeserean section] was borderline significant (p<0.10).

Conclusion

Presence of PDA and gestational age were the important risk factors associated with development of GM-IVH.

Correlation of quantitative texture analysis of cranial ultrasound with later neurobehavior in preterm infants

The purpose of the study was to evaluate the association between a quantitative texture analysis of early neonatal brain ultrasound images and later neurobehavior in preterm infants. A prospective cohort study including 120 preterm (<33 wk of gestational age) infants was performed. Cranial ultrasound images taken early after birth were analyzed in six regions of interest using software based on texture analysis. The resulting texture scores were correlated with the Neonatal Behavioural Assessment Scale (NBAS) at term-equivalent age. The ability of texture scores, in combination with clinical data and standard ultrasound findings, to predict the NBAS results was evaluated. Texture scores were significantly associated with all but one NBAS domain and better predicted NBAS results than clinical data and standard ultrasound findings. The best predictive value was obtained by combining texture scores with clinical information and ultrasound standard findings (area under the curve = 0.94). We conclude that texture analysis of neonatal cranial ultrasound-extracted quantitative features that correlate with later neurobehavior has a higher predictive value than the combination of clinical data with abnormalities in conventional cranial ultrasound.

Selective exposure of the fetal lung and skin/amnion (but not gastro-intestinal tract) to LPS elicits acute systemic inflammation in fetal sheep

Inflammation of the uterine environment (commonly as a result of microbial colonisation of the fetal membranes, amniotic fluid and fetus) is strongly associated with preterm labour and birth. Both preterm birth and fetal inflammation are independently associated with elevated risks of subsequent short- and long-term respiratory, gastro-intestinal and neurological complications. Despite numerous clinical and experimental studies to investigate localised and systemic fetal inflammation following exposure to microbial agonists, there is minimal data to describe which fetal organ(s) drive systemic fetal inflammation. We used lipopolysaccharide (LPS) from E.coli in an instrumented ovine model of fetal inflammation and conducted a series of experiments to assess the systemic pro-inflammatory capacity of the three major fetal surfaces exposed to inflammatory mediators in pregnancy (the lung, gastro-intestinal tract and skin/amnion). Exposure of the fetal lung and fetal skin/amnion (but not gastro-intestinal tract) caused a significant acute systemic inflammatory response characterised by altered leucocytosis, neutrophilia, elevated plasma MCP-1 levels and inflammation of the fetal liver and spleen. These novel findings reveal differential fetal organ responses to pro-inflammatory stimulation and shed light on the pathogenesis of fetal systemic inflammation after exposure to chorioamnionitis.

Childhood cognitive development after fetal growth restriction

OBJECTIVE

To examine the relationship between prenatal umbilical artery (UA) and internal carotid artery (ICA) Doppler findings and cognitive development at 3 and 6 years in low-birth-weight children.

METHODS

This was a study of 209 low-birth-weight (< 10(th) centile) children born after 28 gestational weeks with UA resistance index (RI) measured within 2 weeks before delivery. Children with normal UA- and ICA-RI were defined as small-for-gestational age (SGA) and those with abnormal UA or ICA Doppler findings as having fetal growth restriction (FGR). Cognitive ability at 3 and 6 years' corrected age was assessed using the fourth edition of the Stanford-Binet Intelligence Scale (SBIS) and compared between SGA and FGR groups. An SBIS score < 85 was considered to indicate delayed development.

RESULTS

The median gestational age at diagnosis of abnormal fetal growth was 36.6 (range, 28-41) weeks. There were 87 (41.6%) children classified as having FGR and 122 (58.4%) as SGA. The mean global SBIS score at 3 years was 109.4 (SD, 22.8) and at 6 years it was 110.5 (SD, 13.9). Overall, 22 (10.5%) children had delayed development at 3 years. Total SBIS scores and individual domain scores did not differ between FGR and SGA groups at 3 or 6 years and similar proportions in each group had delayed development.

CONCLUSION

Abnormal prenatal UA and ICA Doppler findings are not associated with lower developmental scores in low-birth-weight children delivered in the third trimester of pregnancy.

Antenatal variables associated with severe adverse neurodevelopmental outcome among neonates born at less than 32 weeks

OBJECTIVE

To determine the association between antenatal factors and severe adverse neurodevelopmental outcome (ANDO) in preterm infants.

STUDY DESIGN

Neurodevelopmental follow-up was performed in a cohort of babies born at <32.0 weeks' gestation with birth weight <1500 grams between 1999 and 2006. Logistic regression analysis was used to relate obstetric, perinatal and neonatal ultrasonographic predictors to severe ANDO, defined as cerebral palsy or neurodevelopmental impairment, including sensory damage and adjusted development quotient <70.

RESULTS

88.6% (195/220) of surviving babies underwent follow up for a median of 24 months (range 12-96); 45 of them (23%) had ANDO, which was severe in 28 (14.3%). Abnormal ultrasonographic findings (intraventricular hemorrhage grades 3 or 4, periventricular leukomalacia, or ventriculomegaly) were observed in 18 cases (9.2%) and they were significantly associated with severe ANDO (OR 11.8 95% CI 4.0-34.0). Only gestational age at delivery (OR 0.80 95% CI 0.66-0.97), but not intrauterine infection, was independently related to severe ANDO. Infants with severe ANDO born before 28 weeks presented lower umbilical artery pH (7.24±0.1 vs 7.31±0.06, p=0.005) and a significantly higher rate of cesarean delivery (85.7% vs 50%, OR 6 95%CI 1.3-26.3, p=0.03) compared with infants without severe ANDO.

CONCLUSION

Gestational age at delivery and low umbilical artery pH at less than 28 weeks, but not intrauterine infection, are independent risk factors for severe ANDO in babies with birth weight <1500g.

Risk factors for periventricular-intraventricular hemorrhage in premature infants

Periventricular-intraventricular hemorrhage (PV-IVH) is a major cause of neurological disabilities in preterm newborns. This study aimed to determine the perinatal factors associated with PV-IVH. We conducted a retrospective case-control study from preterm infants born at < or =34 weeks of gestation and admitted to Neonatal Intensive Care Units of Seoul National University Children's Hospital and Seoul National University Bundang Hospital between June 2003 and December 2007. Neonates with no cranial sonographic data or infants transferred from other centers after three days of age were excluded. Of 1,044 eligible subjects, 59 infants with PV-IVH grade 2, 3, and 4 were allocated to the case group. The control group consisted of 118 infants without PV-IVH who were matched for gestational age and birth weight to each case of PV-IVH. At the multivariate logistic regression model, metabolic acidosis (odds ratio [OR]: 6.94; 95% confidence interval [CI]: 1.12-43.23) and use of inotropes (OR: 3.70; 95% CI: 1.16-11.84) were associated with an increased risk of PV-IVH. Maternal use of antenatal corticosteroids decreases the risk of PV-IVH (OR: 0.36; 95% CI: 0.14-0.92).

Neurological outcome in preterm small for gestational age infants compared to appropriate for gestational age preterm at the age of 18 months: a prospective study

The aim of this study was to investigate the neurological outcome of premature small for gestational age infants at the corrected age of 18 months by the Hammersmith Infant Neurological Examination. A prospective trial was conducted comparing 41 preterm infants being small for gestational age with 41 appropriate for gestational age infants. Birth weight was significantly lower in small for gestational age infants compared with appropriate for gestational age infants (1724.6 +/- 433 versus 1221 +/- 328 g). There were no significant differences regarding the median gestational age and Apgar scores. Median global scores differ significantly between both groups: 75 (47-78) versus 76 (72-78) for the small for gestational age and appropriate for gestational age infants, respectively. Both groups had optimal scores. In conclusion, although the small for gestational age group scored lower in the Hammersmith Infant Neurological Examination, median global score in both groups was within optimal range.

Systemic endotoxin induces gene expression of inducible nitric oxide synthase in fetal rat brain

BACKGROUND

Few studies have examined the response of the fetus under stress, such as with maternal infection. Recent work has indicated that nitric oxide (NO) modulates corticotropin-releasing hormone (CRH) secretion by the hypothalamus, but details of the action of NO on the fetus remain unclear. Therefore, we investigated the expression of inducible nitric oxide synthase (iNOS) mRNA and the response pattern following lipopolysaccharide (LPS) loading using a rat model of fetal infection.

METHODS

Fetuses were delivered by cesarean section on day 20 of gestation and immediately placed in a chamber maintained at 37 degrees C and 100% relative humidity. The LPS group (n=12) was given 400 microg of LPS/100 g body weight, and the physiologic saline group (n=12) was given physiologic saline. Fetuses were then incubated for a further 3 hours. Fetuses were decapitated, the trunk blood was collected immediately after cesarean section or after 3 hours of incubation, and the fetal brains were fixed in formaldehyde and cryopreserved. Coronal cryosections of the brains were prepared, and a (35)S-uridine triphosphate-labeled antisense RNA probe for iNOS was then prepared. In situ hybridization was performed, and iNOS expression was evaluated semiquantitatively on the basis of optical density. In both groups, plasma corticosterone levels were determined with radioimmunoassay.

RESULTS

Expression of iNOS mRNA was not noted in the physiologic saline group (3 hours postpartum). In the LPS group, iNOS mRNA expression was observed in the subfornical organ, but not in the paraventricular nucleus. Plasma corticosterone levels were significantly elevated in the LPS group.

CONCLUSIONS

In 20-day-old rat fetuses, the hypothalamic-pituitary-adrenal axis was already mobilized in response to LPS-induced stress. These results suggest that iNOS is not involved in the acute response of the hypothalamic-pituitary-adrenal axis to LPS challenge in 20-day-old rat fetuses.

''Intraventricular'' hemorrhage and cystic periventricular leukomalacia in preterm infants: how are they related?

Intraventricular hemorrhage and cystic periventricular leukomalacia are often co-occurring characteristics of brain damage in preterm infants. Using data from 1016 infants born before 30 completed weeks' gestational age, we sought to clarify the relationship between severe intraventricular hemorrhage and cystic periventricular leukomalacia, with special emphasis on common antecedents and potential confounding. After comparing risk factors for intraventricular hemorrhage grades 1 through 4 and cystic periventricular leukomalacia, it appears the risk patterns for intraventricular hemorrhage grade 3, intraventricular hemorrhage grade 4, and cystic periventricular leukomalacia differ. The association between intraventricular hemorrhage grade 3 and cystic periventricular leukomalacia differs appreciably from the association between intraventricular hemorrhage grade 4 and cystic periventricular leukomalacia, supporting the notion that intraventricular hemorrhage grade 3 and intraventricular hemorrhage grade 4 are different entities. The presence of intraventricular hemorrhage grade 3 and intraventricular hemorrhage grade 4 increases the risk of cystic periventricular leukomalacia, even after adjusting for potential confounders. This raises the possibility that intraventricular hemorrhage grade 3 and intraventricular hemorrhage grade 4 cause cystic periventricular leukomalacia.

Neurodevelopmental outcome of appropriate and small for gestational age very low birth weight infants

Prematurity and intrauterine growth restriction are associated with neurodevelopment delay. A prospective cohort study included all 96 very low birth weight infants discharged from our neonatal unit from November 2003 to June 2005. The authors compared 41 appropriate and 55 small for gestational age very low birth weight infants' neurodevelopment at 24 months corrected age. Bayley Scales were similar between both groups at 8, 12, 18, and 24 months corrected age even after adjustment for gestational age and improved from 8 to 24 months corrected age. Small for gestational age infants with and without severe intrauterine growth restriction had similar neurodevelopment outcome. Neurodevelopment delay is frequent in very low birth weight infants with no differences between appropriate and small for gestational age. The authors suggest that Bayley Scales evaluation should be performed in every very low birth weight infant at least at 24 months corrected age to detect those requiring therapeutic stimuli.

Inter-observer reliability of the "Assessment of Motor Repertoire--3 to 5 Months" based on video recordings of infants

OBJECTIVE

A detailed analysis of infant motor behaviour can show up indicators for later neurological impairment. The "Assessment of Motor Repertoire--3 to 5 Months", which is part of Prechtl's general movement assessment, could potentially be used for this purpose. The aim of the present study was to investigate inter-observer reliability in this instrument.

METHOD

Video recordings of 24 infants (corrected ages 3 to 5 months, gestational ages 24 to 42 weeks) were analysed by four observers. Kappa and ICC statistics were applied in the reliability analysis.

RESULTS

High to very high inter-observer reliability was found in the assessment of "Fidgety Movements" (kappa 0.75-0.91). Agreement on the "Movement Character" was also high (kappa 0.54-0.84), while the assessment of the "Posture" showed the lowest inter-observer reliability (kappa 0.39-0.56). Moderate to high inter-observer reliability (kappa 0.51-0.84) was achieved in the field "Quality of Other Movements", and moderate in "Repertoire of Co-Existent Other Movements" (kappa 0.51-0.69). Inter-observer reliability in the assessment of the total "Motor Optimality Score" was very high between all four observers as intraclass correlation coefficient (2,1) was 0.87, and ICCs for the pairwise analyses ranged between 0.80 and 0.94.

CONCLUSION

Inter-observer reliability in the "Assessment of Motor Repertoire - 3 to 5 Months" was satisfactory in respect of the subcategories and in case of high and low total optimality scores in pairwise assessments. In the total optimality scores, however, there was some inconsistency in the middle range of the scale.

Magnesium sulphate for women at risk of preterm birth for neuroprotection of the fetus

BACKGROUND

Epidemiological and basic science evidence suggests that magnesium sulphate before birth may be neuroprotective for the fetus.

OBJECTIVES

To assess the effects of magnesium sulphate as a neuroprotective agent when given to women considered at risk of preterm birth.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 August 2008).

SELECTION CRITERIA

Randomised controlled trials of antenatal magnesium sulphate therapy in women threatening or likely to give birth at less than 37 weeks' gestational age. For one subgroup analysis, studies were broadly categorised by the primary intent of the study into "neuroprotective intent", or "other intent (maternal neuroprotective - pre-eclampsia)", or "other intent (tocolytic)".

DATA COLLECTION AND ANALYSIS

At least two authors assessed trial eligibility and quality, and extracted data.

MAIN RESULTS

Five trials (6145 babies) were eligible for this review. Antenatal magnesium sulphate therapy given to women at risk of preterm birth substantially reduced the risk of cerebral palsy in their child (Relative Risk (RR) 0.68; 95% Confidence interval (CI) 0.54 to 0.87; five trials; 6145 infants). There was also a significant reduction in the rate of substantial gross motor dysfunction (RR 0.61; 95% CI 0.44 to 0.85; four trials; 5980 infants). No statistically significant effect of antenatal magnesium sulphate therapy was detected on paediatric mortality (RR 1.04; 95% CI 0.92 to 1.17; five trials; 6145 infants), or on other neurological impairments or disabilities in the first few years of life. Overall there were no significant effects of antenatal magnesium therapy on combined rates of mortality with cerebral palsy, although there were significant reductions for the neuroprotective groups RR 0.85; 95% CI 0.74 to 0.98; four trials; 4446 infants, but not for the other intent subgroups. There were higher rates of minor maternal side effects in the magnesium groups, but no significant effects on major maternal complications.

AUTHORS' CONCLUSIONS

The neuroprotective role for antenatal magnesium sulphate therapy given to women at risk of preterm birth for the preterm fetus is now established. The number of women needed to be treated to benefit one baby by avoiding cerebral palsy is 63 (95% confidence interval 43 to 87). Given the beneficial effects of magnesium sulphate on substantial gross motor function in early childhood, outcomes later in childhood should be evaluated to determine the presence or absence of later potentially important neurological effects, particularly on motor or cognitive function.

Permissive hypercapnia and risk for brain injury and developmental impairment

OBJECTIVE

Permissive hypercapnia is a respiratory-care strategy that is used to reduce the risk for lung injury. The goal of this study was to evaluate whether permissive hypercapnia is associated with higher risk for intraventricular hemorrhage and early childhood behavioral and functional problems than normocapnia among very low birth weight infants.

METHODS

Very low birth weight infants from a statewide cohort were eligible for this study when they were born at <32 weeks' gestational age and survived at least 24 hours. Infants were classified as receiving a permissive hypercapnia, normocapnia, or unclassifiable respiratory strategy during the first 24 hours after birth according to an algorithm based on Pco(2) values and respiratory-treatment decisions that were abstracted from medical charts. Intraventricular hemorrhage diagnosis was also abstracted from the medical chart. Behavioral and functional outcomes were assessed by parent interview at 2 to 3 years. Logistic regression was used to evaluate the relationship between intraventricular hemorrhage and respiratory strategy; ordinary linear regression was used to evaluate differences in behavior and function scores between children by respiratory strategy.

RESULTS

Infants who received a permissive hypercapnia strategy were not more likely to have intraventricular hemorrhage than those with normocapnia. There were no differences in any of the behavioral or functional scores among children according to respiratory strategy. There was a significant interaction between care strategy and 1-minute Apgar score, indicating that infants with lower Apgar scores may be at higher risk for intraventricular hemorrhage with permissive hypercapnia.

CONCLUSIONS

This study suggests that permissive hypercapnia does not increase risk for brain injury and impairment among very low birth weight children. The interaction between respiratory strategy and Apgar score is a potential worrisome exception to this conclusion. Future research should further evaluate the effect of elevated Pco(2) levels among those who are sickest at birth.

Impact of being small-for-gestational age on survival and long-term outcome of extremely premature infants born at 23-27 weeks' gestation

AIM

To evaluate factors affecting survival and long-term outcome of extremely premature infants and to determine whether small for gestational age (SGA) status is an additional risk factor.

METHODS

Survival was analyzed in 193 infants born between 23 and 27 weeks of gestational age (GA) and compared between SGA (n=43) and appropriate for gestational age (AGA) infants. Long-term outcome was assessed in 123 infants at six years of chronological age by neurological evaluation and cognitive tests.

RESULTS

The long-term survival rates were 72.1% for SGA and 84.0% for AGA infants. Significant independent factors affecting survival were GA (OR 1.79 for one week advance, 95% CI 1.36-2.34) and SGA (OR 0.42, 95% CI 0.18-0.997) in comparison with AGA. There were no significant differences in rates of cerebral palsy or mental retardation, 12.0% and 24.0% in SGA, 14.3% and 17.3% in AGA, respectively. Fifty-two percent of SGA and 70% of AGA infants had intact long-term outcome. The perinatal factor found to affect the intact long-term outcome was RDS with surfactant therapy (OR 0.17, 95% CI 0.07-0.45).

CONCLUSION

SGA status as well as short gestation had significant effects on survival. Respiratory complications after birth had a larger detrimental effect on long-term outcome than whether the infant was SGA or AGA.

Growth and neurodevelopment outcome of very low birth weight infants delivered by preeclamptic mothers

AIM

To investigate growth and neurodevelopment outcome of very low birth weight (VLBW) infants delivered by preeclamptic mothers.

METHODS

A cohort including all VLBW infants delivered between December 2003 and May 2005 was followed up to 12 and 18 months corrected age (CA).

EXCLUSION CRITERIA

death before 1 year corrected age, major malformations, deafness and blindness. Weight, length and head circumference were plotted on NCHS curves. Bayley Scales were performed at 12 and 18 months CA.

RESULTS

40 infants in preeclamptic and 46 in control groups were studied. Birth weight and gestational age were 1148 g+/-236 and 1195 g+/-240, and 31.3 weeks+/-1 and 30.6 weeks+/-2 for preeclamptic and control groups, respectively. At 12 and 18 months, CA, weight for age (Z score) was significantly higher in control than in preeclamptic. PDI scores were higher in preeclamptic than in controls at 18 months CA.

CONCLUSIONS

Catch-up of body weight did not occur in the first 18 months CA in preeclamptic infants. Neurodevelopment outcome was better in infants delivered by preeclamptic mothers than in controls at 18 months CA.

Neuroimaging of neonatal encephalopathies

Neonatal brain disorders consist of a wide chapter including brain malformations, hypoxic-ischemic encephalopathy (HIE), intracranial infections, perinatal trauma and metabolic encephalopathy. We will focus here on HIE, intracranial infections (especially materno-fetal infection with or without prolonged and/or premature rupture of membranes) and metabolic encephalopathy, those three conditions being the most frequent so far in our experience. Neonatal stroke is also analyzed. Moreover minor perinatal events might be superimposed on an already damaged (infective, edematous, metabolically abnormal or maldeveloped) brain, highlighting the main role and potential benefits of neuroimaging during the neonatal period. The different methods of brain imaging are thus reported with their advantages and disadvantages.

Magnesium sulphate for women at risk of preterm birth for neuroprotection of the fetus

BACKGROUND

Epidemiological and basic science evidence suggests that magnesium sulphate before birth may be neuroprotective for the fetus.

OBJECTIVES

To assess the effectiveness and safety of magnesium sulphate as a neuroprotective agent when given to women considered at risk of preterm birth.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (October 2006), CENTRAL (The Cochrane Library 2006, Issue 3), MEDLINE (1966 to October 2006), EMBASE (1980 to October 2006), Current Contents (1992 to October 2006), references of retrieved articles, and abstracts submitted to the Society for Pediatric Research (1996 to 2006).

SELECTION CRITERIA

Randomised controlled trials of antenatal magnesium sulphate therapy given to women threatening or likely to give birth at less than 37 weeks' gestational age.

DATA COLLECTION AND ANALYSIS

We independently extracted data regarding clinical outcomes including paediatric mortality, neurologic outcome of survivors (including blindness, deafness, cerebral palsy and major neurosensory disability), and maternal complications and side-effects. At least two authors assessed trial eligibility and quality, and extracted data.

MAIN RESULTS

Four trials (3701 babies) were eligible for this review. No statistically significant effect of antenatal magnesium sulphate therapy was detected on any major paediatric outcome, including mortality (e.g., paediatric mortality relative risk (RR) 0.97; 95% confidence interval (CI) 0.74 to 1.28; four trials; 3701 infants), and neurological outcomes in the first few years of life, including cerebral palsy (RR 0.77; 95% CI 0.56 to 1.06; four trials; 3701 infants), neurological impairments or disabilities. There were also no significant effects of antenatal magnesium therapy on combined rates of mortality with neurologic outcomes. There was a significant reduction in the rate of substantial gross motor dysfunction (RR 0.56; 95% CI 0.33 to 0.97; two trials; 2848 infants). There were higher rates of minor maternal side-effects in the magnesium groups, but no significant effects on major maternal complications.

AUTHORS' CONCLUSIONS

The role for antenatal magnesium sulphate therapy as a neuroprotective agent for the preterm fetus is not yet established. Given the possible beneficial effects of magnesium sulphate on gross motor function in early childhood, outcomes later in childhood should be evaluated to determine the presence or absence of later potentially important neurologic effects, particularly on motor or cognitive function. Further information will be available from one of the studies where outcomes are being evaluated again at eight to nine years of age, and from another trial currently in progress.

Long-term neurodevelopmental outcome of triplets

OBJECTIVE

To analyze the incidence of neurodevelopmental disabilities in triplets and to find out possible connection between the outcome and perinatal events.

DESIGN

Retrospective cohort study of 94 triplets and their outcome at 24-144 months of age correlated with gestational age, birth weight, pregnancy complications, early neonatal period, neonatal cranial ultrasound, period of birth (1985-1995, 1996-2000) and type of antenatal care.

RESULTS

Sixty-two triplets are healthy, 15 suffer cerebral palsy (CP) and 17 minimal cerebral dysfunction (MCD). Adverse outcome correlates significantly with prematurity, low birth weight and maternal age. In multivariate analysis, both cerebral palsy and minor disabilities correlate significantly with early neonatal complications, neonatal cranial ultrasound with later CP (p<0.01), and MCD with preterm rupture of membranes (p=0.047). Children conceived spontaneously do worse than those born after assisted reproduction (p=0.004), those born in the time period 1996-2000 do better than those born before (p=0.021). Seventy-seven percent (77%) of newborns delivered in the time period 1996-2000 and after level 1 antenatal care was introduced, compared with 54% being delivered in the time period before 1996 and with less meticulous types of antenatal care, remain healthy (p=0.015).

CONCLUSION

Triplets are still at high risk for long-term neurodevelopmental complications. Stringent perinatal care might appear important determinant of their long-term outcome.

Lower mortality but higher neonatal morbidity over a decade in very preterm infants

Better perinatal care has led to better survival of very preterm children, but may or may not have increased the number of children with cerebral and pulmonary morbidity. We therefore investigated the relationship between changes in perinatal care during one decade, and short-term outcome in very preterm infants. Perinatal risk factors and their effects on 28-day and in-hospital mortality, and on intraventricular haemorrhage and bronchopulmonary dysplasia (BPD) in survivors, were compared in two surveys of very preterm singleton infants in the Netherlands. Between 1983 and 1993, 28-day mortality decreased from 52.1% to 31.8% in infants of 25-27 weeks' gestation and from 15.2% to 11.3% in infants of 28-31 weeks' gestation. The incidence of intraventricular haemorrhage in survivors did not change (44.4% and 43.3% in infants of 25-27 weeks' gestation, and 29.0% and 24.0% in infants of 28-31 weeks' gestation). The incidence of BPD in survivors increased from 40.3% to 60.0% in infants of 25-27 weeks' gestation and remained similar in infants of 28-31 weeks' gestation (8.5% and 9.8% respectively). In multivariable analysis, higher mortality was associated with congenital malformation, low gestational age, low birthweight, no administration of steroids before birth, low Apgar scores and intraventricular haemorrhage, in 1983 as well in 1993, and with male gender in 1993. The effect of maternal age on mortality diminished significantly between 1983 and 1993. Intraventricular haemorrhage in surviving children was associated with low gestational age and artificial ventilation, both in 1983 and in 1993. The effect of artificial ventilation on the incidence of intraventricular haemorrhage diminished significantly between 1983 and 1993. BPD was associated with low gestational age and artificial ventilation, both in 1983 and in 1993, and with low birthweight and caesarean section in 1993. We conclude that the better survival of very preterm infants, especially of those of 25-27 weeks' gestation, has been accompanied by a similar incidence (and thus with an increased absolute number) of children with intraventricular haemorrhage and by an increased incidence of children with BPD.

Risks for low intellectual performance related to being born small for gestational age are modified by gestational age

OBJECTIVE

We sought to study whether the association between being born small for gestational age and risk for low intellectual performance was modified by gestational age.

METHODS

A population-based cohort study was conducted of 352,125 boys who were born between 28 and 43 completed weeks of gestation from 1973 to 1981 in Sweden. Risk for low intellectual performance at military conscription, estimated as odds ratios with 95% confidence intervals was measured.

RESULTS

Compared with men who were born preterm (28-36 weeks) and had normal birth weight for gestational age, men who were born preterm and had a very low birth weight for gestational age were not at increased risk for low intellectual performance. In contrast, men who were born preterm with a very short birth length or a very small head circumference for gestational age faced a near doubled risk for low intellectual performance compared with their appropriate peers. Among men who were born at term (37-41 weeks), risk for low intellectual performance was increased among those with very or moderately small birth weight, birth length, or head circumference for gestational age.

CONCLUSIONS

During early stages of gestation, growth in length and head circumference may be more important for intellectual development than weight increase. Future studies on size at birth and intellectual performance should consider also including anthropometric measurements other than birth weight.

Ante- and perinatal factors for cerebral palsy: case-control study in Estonia

Establishing consistency between cerebral palsy registries in reporting of new cases enables more effective collaboration in terms of researching predisposing factors. To identify antenatal and intrapartum risk factors for cerebral palsy in the Estonian population, we undertook a matched case-control study of 153 children with cerebral palsy, ascertained from a population-based survey. One hundred two maternal, antenatal, and intrapartum variables were initially retrieved from medical records. Main outcome measures were the odds ratio estimates of relative risk of cerebral palsy. As a result of the study, and considering the whole spectrum of severity, the relevant risk factors during pregnancy were bleeding after 20 weeks, anemia in the second half of pregnancy, pregnancy-induced hypertension in the second half of pregnancy, and preeclampsia. The most important intrapartum factors were premature birth, placental abruption, an acute hypoxic event during delivery, and any fetal presentation other than vertex. Predisposing factors related to neonatal condition were an Apgar score < or = 7 at the first and fifth minutes of life, hypoxic-ischemic encephalopathy, and assisted ventilation. Our findings suggest that intrapartum factors, including those hypothetically realized through hypoxic-ischemic pathways, are not of low importance in the etiology of cerebral palsy.

Could the consequences of premature delivery be further attenuated by means of new prenatal strategies?

The last 10 years have already seen improvements in the short- and long-term prognosis for premature neonates. Nevertheless, progress in the prenatal evaluation of predictive factors for neonatal diseases and more detailed and reliable knowledge of fetal physiology could allow the development of new treatments with consequent expectations of further improvements in the prognosis for such premature newborns. Global strategies for the management of preterm labour, ranging from a policy for prenatal transfer to centres offering the appropriate level of perinatal care, should continue to be expanded, and long-term evaluations must also be continued.

Maternal LPS induces cytokines in the amniotic fluid and corticotropin releasing hormone in the fetal rat brain

Perinatal infections are a risk factor for fetal neurological pathologies, including cerebral palsy and schizophrenia. Cytokines that are produced as part of the inflammatory response are proposed to partially mediate the neurological injury. This study investigated the effects of intraperitoneal injections of lipopolysaccharide (LPS) to pregnant rats on the production of cytokines and stress markers in the fetal environment. Gestation day 18 pregnant rats were treated with LPS (100 μg/kg body wt ip), and maternal serum, amniotic fluid, placenta, chorioamnion, and fetal brain were harvested at 1, 6, 12, and 24 h posttreatment to assay for LPS-induced changes in cytokine protein (ELISA) and mRNA (real-time RT-PCR) levels. We observed induction of proinflammatory cytokines interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) as well as the anti-inflammatory cytokine IL-10 in the maternal serum within 6 h of LPS exposure. Similarly, proinflammatory cytokines were induced in the amniotic fluid in response to LPS; however, no significant induction of IL-10 was observed in the amniotic fluid. LPS-induced mRNA changes included upregulation of the stress-related peptide corticotropin-releasing factor in the fetal whole brain, TNF-α, IL-6, and IL-10 in the chorioamnion, and TNF-α, IL-1β, and IL-6 in the placenta. These findings suggest that maternal infections may lead to an unbalanced inflammatory reaction in the fetal environment that activates the fetal stress axis.

Outcome in preterm small for gestational age infants compared to appropriate for gestational age preterms at the age of 2 years: a prospective study

OBJECTIVES

To investigate the effects of small for gestational age (SGA) in preterm infants on growth and development until the age of 22 months.

STUDY DESIGN

Seventy-four preterm infants being born SGA (birth weight <10th percentile) were compared with 74 appropriate for gestational age (AGA) infants matched prospectively according to gestational age with respect to growth parameters and neurodevelopment (using Griffiths developmental scores) at the age of 22 months corrected age.

RESULTS

Birth weight was significantly lower in SGA-infants compared to AGA-infants (1503 g (430-2205 g) versus 1995 g (680-3300 g); P<0.0001 (median and range)). There were no significant differences regarding the median gestational age (34 weeks), gender distribution, mode of delivery, umbilical artery pH, and APGAR-scores. Mean Griffiths-scores did not differ significantly between both groups (96.7% versus 97.6%). Developmental retardation was diagnosed in 9 SGA-infants versus 10 AGA-infants. Within the total group a positive correlation was observed between gestational age and developmental scoring. Body weight, head circumference, and height were significantly lower in SGA-infants at 22 months corrected age.

CONCLUSION

No significant differences regarding neurodevelopmental outcome at 22 months were observed between SGA- and AGA-infants. SGA-infants did not show catch-up growth.

A population-based study of prognostic factors related to major disability in very preterm survivors

OBJECTIVE

This study was conducted to determine the rates and risk factors for major disability in very preterm survivors born to residents of Nova Scotia, Canada between 1992 and 1996.

STUDY DESIGN

A cohort study was conducted of all 355 infants born to Nova Scotia residents between 22 and 30 weeks gestation. Major disability was defined by mental development index <70, moderate or severe cerebral palsy, bilateral visual acuity <20/200, or deafness requiring bilateral hearing aids. Logistic regression analysis was used to determine which factors were significantly associated with major disability.

RESULTS

Of the infants who survived 1 year and had follow-up data, 21 (8.3%) developed a major disability. Cystic periventricular leukomalacia (PVL), hypernatremia and surgery requiring general anesthesia were independently associated with the development of a major disability.

CONCLUSION

This study confirms the association between cystic PVL and major disability observed in other studies. Surgery and hypernatremia will be important to verify in future studies since preventive measures may be possible.

Chorioamnionitis and brain injury

The limited available evidence supports a strong association of chorioamnionitis with neonatal encephalopathy and CP in the term infant. The association of chorioamnionitis with depressed Apgar scores or neonatal seizures and with CP is equivocal in the preterm infant. Different study results may be related to differences in study populations, perhaps specifically to differences in susceptibility by stages of neurologic development as well as differences in gene frequencies associated with inflammation and thrombophilia. We require further understanding of the normal roles of cytokines in brain development, pregnancy, and inflammatory homeostasis before clinical interventions directed at cytokines, their receptors, or the inflammatory process are considered.