Why birthplace still matters for infants born before 32 weeks: Infant mortality associated with birth at 22-31 weeks' gestation in non-tertiary hospitals in Victoria over two decades

Outcomes to 5 years of outborn versus inborn infants <32 weeks in Western Australia: a cohort study of infants born between 2005 and 2018

OBJECTIVE

We compared mortality and morbidity of inborn versus outborn very preterm infants <32 weeks' gestation in Western Australia (WA) between 2005 and 2018.

DESIGN

Retrospective cohort study.

PATIENTS

Infants <32 weeks' gestation who were born in WA.

MAIN OUTCOME MEASURES

Mortality was assessed as death before discharge home from the tertiary neonatal intensive care unit. Short-term morbidities included combined brain injury (intracranial haemorrhage grade ≥3 and cystic periventricular leukomalacia) and other major neonatal outcomes. Developmental assessments at age 2, 3 and 5 years were evaluated. We performed multivariable logistic regression analysis of outborn status on outcomes, controlling for gestational age, birth weight z-score, sex and multiple birth.

RESULTS

A total of 4974 infants were born in WA between 22 and 32 weeks' gestation between 2005 and 2018 of which 4237 (89.6%) were inborn and 443 (10.4%) were outborn. Overall mortality to discharge was higher in outborn infants (20.5% (91/443) vs 7.4% (314/4237); adjusted OR (aOR) 2.44, 95% CI 1.60 to 3.70, p<0.001). Outborn infants had higher rates of combined brain injury than those inborn (10.7% (41/384) vs 6.0% (246/4115); aOR 1.98, 95% CI 1.37 to 2.86), p<0.001). No difference in up to 5-year developmental measures was detected. Follow-up data were available for 65% of outborn and 79% of inborn infants.

CONCLUSIONS

Outborn preterm infants <32 weeks in WA had increased odds of mortality and combined brain injury than those inborn. Developmental outcomes up to 5 years were similar between groups. Loss to follow-up may have impacted the long-term comparison.

Association of Rural and Frontier Residence with Very Preterm and Very Low Birth Weight Delivery in Nonlevel III NICUs

OBJECTIVE

Delivery of very preterm and very low birth weight neonates (VPT/VLBW) in a nonlevel III neonatal intensive care unit (NICU) increases risk of morbidity and mortality. Study objectives included the following: (1) Determine incidence of VPT/VLBW delivery (<32 weeks gestational age and/or birth weight <1,500 g), in nonlevel III units in Colorado; (2) Evaluate the independent association between residence and nonlevel III unit delivery; (3) Determine the incidence of and factors associated with postnatal transfer.

STUDY DESIGN

This retrospective cohort study used 2007 to 2016 Colorado birth certificate data. Demographic and clinical characteristics by VPT/VLBW delivery in level III NICUs versus nonlevel III units were compared using Chi-square analyses. Multivariable logistic regression was used to estimate the independent association between residence and VPT/VLBW delivery.

RESULTS

Among patients, 897 of 10,015 (8.96%) VPT/VLBW births occurred in nonlevel III units. Compared with infants born to pregnant persons in urban counties, infants born to those residing in rural (adjusted odds ratio [AOR] = 1.58, 95% confidence interval [CI]: 1.33, 1.88) or frontier (AOR = 3.19, 95% CI: 2.14, 4.75) counties were more likely to deliver in nonlevel III units and to experience postnatal transfer within 24 hours (rural AOR = 2.24, 95% CI: 1.60, 3.15; frontier AOR = 3.91, 95% CI: 1.76, 8.67). Compared with non-Hispanic Whites, Hispanics were more likely to deliver VPT/VLBW infants in nonlevel III units (AOR = 1.36, 95% CI: 1.15, 1.61).

CONCLUSION

A significant number of VPT/VLBW neonates were born in nonlevel III units with associated disparities by race/ethnicity and nonurban residence.

KEY POINTS

· Preterm delivery in a nonlevel III NICU increases risk of neonatal morbidity and mortality.. · A significant number of preterm deliveries in Colorado occur in hospitals with nonlevel III NICUs.. · Disparities in preterm delivery by race/ethnicity and nonurban residence exist..

Survival and neurodevelopmental impairment of outborn preterm infants at 5.5 years of age: an EPIPAGE-2 prospective, matched study using multiple imputation

OBJECTIVE

To determine whether birth outside a level-3 centre (outborn) is associated with a difference in the combined outcome of mortality or moderate-to-severe neurological impairment at 5.5 years of age compared with birth in a level-3 centre (inborn) when antenatal steroids and gestational age (GA) are accounted for.

DESIGN

Individual matched study nested within a prospective cohort. Each outborn infant was matched using GA and antenatal steroids with a maximum of four inborns. Conditional logistic regression was used to calculate ORs before being adjusted using maternal and birth characteristics. Analyses were carried out after multiple imputation for missing data.

SETTING

EPIPAGE-2 French national prospective cohort including births up to 34 weeks GA inclusive.

PATIENTS

Outborn and inborn control infants selected between 24 and 31 weeks GA were followed in the neonatal period and to 2 and 5.5 years. 3335 infants were eligible of whom all 498 outborns and 1235 inborn infants were included-equivalent to 2.5 inborns for each outborn.

MAIN OUTCOME MEASURE

Survival without moderate-to-severe neurodevelopmental impairment at 5.5 years.

RESULTS

Chorioamnionitis, pre-eclampsia, caesarian birth and small-for-dates were more frequent among inborns, and spontaneous labour and antepartum haemorrhage among outborns. There was no difference in the main outcome measure at 5.5 years of age (adjusted OR 1.09, 95% CI 0.82 to 1.44); sensitivity analyses suggested improved outcomes at lower GAs for inborns.

CONCLUSION

In this GA and steroid matched cohort, there was no difference in survival without moderate-to-severe neurodevelopmental impairment to 5.5 years of age between inborn and outborn very preterm children. This suggests steroids might be important in determining outcomes.

Impact of Outborn/Inborn Birth Status of Infants Born at <29 Weeks of Gestation on Neurodevelopmental Impairment: A Nationwide Cohort Study in Korea

This study designed to evaluate the short- and long-term outcomes of outborn and inborn preterm infants enhancing the regional perinatal system in South Korea. It is a prospective cohort study of the Korean neonatal network database for infants born at <29 weeks of gestation between 2013 and 2015. Of 2995 eligible infants, 312 were outborn, and 976 completed the assessment of long-term outcome at 18-24 months of corrected age. The mean gestational age was significantly younger in outborn infants than in inborn infants (p = 0.004). The mean Apgar score at 5 min was higher in inborn infants (p = 0.046). More inborn preterm infants died before discharge (p < 0.001); however, most of the other short-term outcomes occurred significantly more often in outborn infants than in inborn infants. The outborn infants had higher odds of neurodevelopmental impairment (adjusted odds ratio (aOR) 2.412, 95% confidence interval (CI) 1.585-3.670), cerebral palsy (aOR 4.460, 95% CI 2.249-8.845) and developmental impairment (aOR 2.238, 95% CI 1.469-3.408). In preterm infants, the location of birth may be a key factor influencing short- and long-term outcomes. Thus, to provide adequate care and efficiently allocate medical resources to high-risk preterm infants, nationwide regional perinatal systems need to be improved and standardized.

Protecting the brain of the micropreemie

Advances in perinatal care have seen substantial improvements in survival without disability for extremely preterm infants. Protecting the developing brain and reducing neurodevelopmental sequelae of extremely preterm birth are strategic priorities for both research and clinical care. A number of evidence-based interventions exist for neuroprotection in micropreemies, inclusive of prevention of preterm birth and multiple births with implantation of only one embryo during in vitro fertilisation, as well as antenatal care to optimize fetal wellbeing, strategies for supporting neonatal transition, and neuroprotective developmental care. Avoidance of complications that trigger ischemia and inflammation is vital for minimizing brain dysmaturation and injury, particularly of the white matter. Neurodevelopmental surveillance, early diagnosis of cerebral palsy and early intervention are essential for optimizing long-term outcomes and quality of life. Research priorities include further evaluation of putative neuroprotective agents, and investigation of common neonatal interventions in trials adequately powered to assess neurodevelopmental outcome.

Changes in long-term survival and neurodevelopmental disability in infants born extremely preterm in the post-surfactant era

Extremely preterm birth before 28 weeks' gestation accounts for less than 1% of births in high-income countries but is associated with high rates of perinatal and infant mortality, and of neurodevelopmental disability in surviving children. Survival rates have increased over time, both overall, and within each week of gestational age since the introduction of exogenous surfactant into clinical care in the early 1990s. However, rates of major neurodevelopmental disability in survivors, whether they be in early childhood or at school-age, have not clearly improved in parallel with the increases in survival. An important strategy to improve survival free of major neurodevelopmental disability is to birth extremely preterm infants in a tertiary perinatal center, where specialist obstetric care for the mother and ongoing intensive care for the infant can both be provided without the potential morbidities associated with postnatal transfer.

How can obstetricians improve outcomes for infants born extremely preterm?

Prematurity remains a leading cause of perinatal morbidity and mortality, and also has significant implications for long-term health. Obstetricians have a key role to play in improving outcomes for infants born at extremely preterm gestations. This review explores the evidence for interventions available to obstetricians caring for women at risk of birthing at extremely preterm gestations, including antenatal corticosteroids, magnesium sulfate, tocolysis and antibiotics. It also addresses the importance of strategies to facilitate safe in-utero transfer, to maximise the chance of extremely preterm births occurring in tertiary centers, and the clinical value of strategies by which preterm birth can be predicted. The paper concludes with an appraisal of evidence for different modes of birth at extremely preterm gestations, and for delayed cord clamping.

Outcomes of outborn very-low-birth-weight infants in Japan

BACKGROUND

Outcomes of prenatal covariate-adjusted outborn very-low-birth-weight infants (VLBWIs) (≤1500 g) remain uncertain.

OBJECTIVE

To compare morbidity and mortality between outborn and inborn VLBWIs.

DESIGN

Observational cohort study using inverse-probability-of-treatment weighting.

SETTING

Neonatal Research Network of Japan.

PATIENTS

Singleton VLBWIs with no major anomalies admitted to a neonatal intensive care unit from 2012 to 2016.

METHODS

Inverse-probability-of-treatment weighting with propensity scores was used to reduce imbalances in prenatal covariates (gestational age (GA), birth weight, small for GA, sex, maternal age, premature rupture of membranes, chorioamnionitis, preeclampsia, maternal diabetes mellitus, antenatal steroids and caesarean section). The primary outcome was severe intraventricular haemorrhage (IVH). The secondary outcomes were outcomes at resuscitation, other neonatal morbidities and mortality.

RESULTS

The full cohort comprised 15 842 VLBWIs (668 outborns). The median (IQR) GA and birth weight were 28.9 (26.4-31.0) weeks and 1128 (862-1351) g for outborns and 28.7 (26.3-30.9) weeks and 1042 (758-1295) g for inborns. Outborn VLBWIs had a higher incidence of severe IVH (8.2% vs 4.1%; OR, 3.45; 95% CI 1.16 to 10.3) and pulmonary haemorrhage (3.7% vs 2.8%; OR, 5.21; 95% CI 1.41 to 19.2). There were no significant differences in Apgar scores, oxygen rates at delivery, intubation ratio at delivery, persistent pulmonary hypertension of the newborn, IVH of any grade, periventricular leukomalacia, chronic lung disease, oxygen at discharge, patent ductus arteriosus, retinopathy of prematurity, necrotising enterocolitis, sepsis or mortality.

CONCLUSION

Outborn delivery of VLBWIs was associated with an increased risk of severe IVH.

Changing consumption of resources for respiratory support and short-term outcomes in four consecutive geographical cohorts of infants born extremely preterm over 25 years since the early 1990s

OBJECTIVES

It is unclear how newer methods of respiratory support for infants born extremely preterm (EP; 22-27 weeks gestation) have affected in-hospital sequelae. We aimed to determine changes in respiratory support, survival and morbidity in EP infants since the early 1990s.

DESIGN

Prospective longitudinal cohort study.

SETTING

The State of Victoria, Australia.

PARTICIPANTS

All EP births offered intensive care in four discrete eras (1991-1992 (24 months): n=332, 1997 (12 months): n=190, 2005 (12 months): n=229, and April 2016-March 2017 (12 months): n=250).

OUTCOME MEASURES

Consumption of respiratory support, survival and morbidity to discharge home. Cost-effectiveness ratios describing the average additional days of respiratory support associated per additional survivor were calculated.

RESULTS

Median duration of any respiratory support increased from 22 days (1991-1992) to 66 days (2016-2017). The increase occurred in non-invasive respiratory support (2 days (1991-1992) to 51 days (2016-2017)), with high-flow nasal cannulae, unavailable in earlier cohorts, comprising almost one-half of the duration in 2016-2017. Survival to discharge home increased (68% (1991-1992) to 87% (2016-2017)). Cystic periventricular leukomalacia decreased (6.3% (1991-1992) to 1.2% (2016-2017)), whereas retinopathy of prematurity requiring treatment increased (4.0% (1991-1992) to 10.0% (2016-2017)). The average additional costs associated with one additional infant surviving in 2016-2017 were 200 (95% CI 150 to 297) days, 326 (183 to 1127) days and 130 (70 to 267) days compared with 1991-1992, 1997 and 2005, respectively.

CONCLUSIONS

Consumption of resources for respiratory support has escalated with improved survival over time. Cystic periventricular leukomalacia reduced in incidence but retinopathy of prematurity requiring treatment increased. How these changes translate into long-term respiratory or neurological function remains to be determined.

International comparisons of neurodevelopmental outcomes in infants born very preterm

We summarise rates of survival and neurodevelopmental impairment in very (<32 weeks' gestation) and extremely (<28 weeks' gestation) preterm infants using data from recent meta-analyses. Methodological issues that require consideration when comparing international data are highlighted using examples of population-based or multi-centre cohorts of children born extremely preterm. The impact of baseline population, outcome definition, gestational age assessment, age at neurodevelopmental assessment, year of birth and follow-up rates are discussed. The impact of the intensity of perinatal care and of post-discharge management on survival and neurodevelopmental outcomes is also discussed. There is a future need for harmonisation of data collection and for more accurate and standardised reporting of neurodevelopmental outcomes in very preterm children.

The impact of level of neonatal care provision on outcomes for preterm babies born between 27 and 31 weeks of gestation, or with a birth weight between 1000 and 1500 g: a review of the literature

OBJECTIVE

There is evidence that birth and care in a maternity service associated with a neonatal intensive care unit (NICU) is associated with improved survival in preterm babies born at <27 weeks of gestation. We conducted a systematic review to address whether similar gains manifested in babies born between 27+0 and 31+6 weeks (hereafter 27 and 31 weeks) of gestation, or in those with a birth weight between 1000 and 1500 g.

METHODS

We searched Embase, Medline and CINAHL databases for studies comparing outcomes for babies born between 27 and 31 weeks or between 1000 and 1500 g birth weight, based on designation of the neonatal unit where the baby was born or subsequently cared for (NICU vs non-NICU setting). A modified QUIPS (QUality In Prognostic Studies) tool was used to assess quality.

RESULTS

Nine studies compared outcomes for babies born between 27 and 31 weeks of gestation and 11 studies compared outcomes for babies born between 1000 and 1500 g birth weight. Heterogeneity in comparator groups, birth locations, gestational age ranges, timescale for mortality reporting, and description of morbidities facilitated a narrative review as opposed to a meta-analysis.

CONCLUSION

Due to paucity of evidence, significant heterogeneity and potential for bias, we were not able to answer our question-does place of birth or care affect outcomes for babies born between 27 and 31 weeks? This supports the need for large-scale research to investigate place of birth and care for babies born in this gestational age range.

Outcomes of outborn extremely preterm neonates admitted to a NICU with respiratory distress

OBJECTIVE

To compare the risk of mortality and morbidity between outborn and propensity score-matched inborn extremely preterm neonates.

SETTING

Multiple neonatal intensive care units (NICU) across the USA.

PATIENTS

Singleton neonates born at 22-29 weeks' gestation with no major anomalies who were admitted to a NICU and discharged between 2000 and 2014. Outborn neonates were restricted to those who transferred into a NICU on the day of birth.

METHODS

The association between inborn-outborn status and the time-to-event outcomes of in-hospital mortality and necrotising enterocolitis (NEC) were assessed using Cox proportional hazards regression. Logistic regression was used to assess the remaining secondary outcomes: retinopathy of prematurity requiring treatment (tROP), chronic lung disease (CLD), periventricular leucomalacia (PVL) and severe intraventricular haemorrhage (IVH). Since outborn status was not random, we used 1:1 propensity score matching to reduce the imbalance in illness severity.

RESULTS

There were 59 942 neonates (7991 outborn) included in the study. Outborn neonates had poorer survival than inborns and higher rates of NEC, severe IVH, tROP and PVL. Inborn-outborn disparities in mortality were reduced over the study period. When analysing the matched cohort (6524 matched pairs), outborns were less likely to die in-hospital compared with inborns (HR 0.84, 95% CI 0.77 to 0.91). However, outborns experienced higher rates of NEC (HR 1.14, 95% CI 1.04 to 1.25), severe IVH (OR 1.52, 95% CI 1.38 to 1.68), tROP (OR 1.45, 95% CI 1.25 to 1.69) and CLD (OR 1.12, 95% CI 1.01 to 1.24).

CONCLUSION

Additional research is needed to understand the contributors to increased morbidity for outborn extremely preterm neonates and identify interventions that mitigate this risk.

The role of the obstetrician in the prevention of retinopathy of prematurity

This review underlines the important role that obstetricians play in the prevention of retinopathy of prematurity. Efforts predominately focus on predicting which pregnant women are at highest risk of preterm birth, instigating treatments to prevent pre-eclampsia, fetal growth restriction and maternal infection which could lead to iatrogenic or spontaneous preterm birth, and optimizing care when preterm birth is inevitable. More broadly, optimizing maternal health pre-conception through stopping smoking, improving diet, reducing obesity with its associated gestational diabetes, and treating hypertension may reduce preterm birth and other pregnancy complications. This is a message that all healthcare professionals including obstetricians, neonatologists and GPs, nursing and midwifery staff need to communicate all women and men who are contemplating having a baby.

Adequacy of antenatal steroids, rather than place of birth, determines survival to discharge in extreme prematurity in North Queensland

AIM

The Townsville Hospital cares for babies in a large geographical area, many of who are outborn, are of Aboriginal or Torres Strait Islander origin and have families who reside in areas of deprivation. This study examined the outcomes of babies born at all locations in North Queensland to assess the predictors of poor outcomes.

METHODS

A retrospective observational study examined the survival of 313 babies born from 22 completed weeks gestation to 27 + 6 weeks gestation in North Queensland between January 2010 and December 2016. Additional analyses were performed for the 300 non-syndromal babies whose mothers usually resided in North Queensland, studying demographics of gestation, gender, birthweight, Indigenous status, regionality of maternal residence and adequacy of antenatal steroids. Short-term morbidities of intraventricular haemorrhage/periventricular leukomalacia (IVH/PVL), surgical necrotizing enterocolitis, retinopathy of prematurity requiring treatment and chronic lung disease and death were studied in relation to demographic factors and clinical treatment.

RESULTS

Adequacy of steroids was significantly associated with a decreased mortality odds ratio of 2.872 (95% confidence interval 1.228-6.715), whilst no difference in outcome was seen by retrieval status or ethnic origin. Babies from remote locations were at increased risk for IVH/PVL, 2.334 (1.037-5.255). Male babies suffered more chronic lung disease, 1.608 (1.010-2.561), and IVH/PVL, 2.572 (1.215-5.445). Aboriginal and Torres Strait Islander babies were at lower risk of IVH/PVL.

CONCLUSIONS

Steroids should be administered wherever there is any possibility of the provision of intensive care for periviable babies. Place of birth and ethnicity of mother should not unduly influence antenatal counselling.

Does earlier arrival of the retrieval team improve short-term outcomes in outborn extremely premature infants?

AIM

The risk of mortality and morbidity is increased in outborn, extremely premature infants. We aim to determine whether earlier arrival of the retrieval team after the birth of infants less than 29 weeks gestation improves short-term mortality and morbidity.

METHODS

This is a retrospective analysis of a cohort of infants less than 29 weeks gestation who were retrieved to the Royal Brisbane and Women's Hospital (RBWH) over a 5-year period. Demographic information regarding the infant and mother, retrieval team arrival time and outcome data was collected. Primary outcomes investigated were mortality prior to discharge from hospital or a composite of mortality or severe intraventricular haemorrhage (IVH).

RESULTS

Data on 105 infants were analysed; 88 infants (83.8%) survived to discharge home, and 79 (75.2%) survived to discharge without severe IVH. On univariate analysis, there was no significant association between age at arrival of the retrieval team and death prior to discharge (P = 0.94) or death prior to discharge or severe IVH (P = 0.83). On logistic regression analysis, age at arrival of retrieval team remained non-significant for a reduction in death prior to discharge and composite of death or severe IVH (P = 0.70 and P = 0.99, respectively).

CONCLUSION

The earlier arrival of the retrieval team is not associated with improved short-term outcomes in outborn, extremely preterm infants who are retrieved and admitted to a tertiary neonatal intensive care unit - for infants where the retrieval team arrived within about 8 h of birth.

Clinical features and outcomes of pregnancies complicated by pre-ecplampsia necessitating in-utero transfer

OBJECTIVES

Pre-eclampsia (PE) is associated with significant risks of adverse perinatal outcomes, often necessitating transfer to a higher level of care for specialist perinatal management. In Victoria, Australia, the Paediatric Infant Perinatal Emergency Retrieval (PIPER) coordinates in-utero transfers of high-risk pregnancies. Our objectives were to report the clinical features and outcomes of women referred to PIPER with a primary diagnosis of PE, and subsequently transferred in-utero.

STUDY DESIGN

A retrospective audit of consecutive pregnancies referred to PIPER in 2013-2014 with a primary diagnosis of pre-eclampsia, ≥20 weeks' gestation and transferred in-utero.

MAIN OUTCOME MEASURES

Severity of disease, gestational age, transfer details and outcome until 7 days post transfer.

RESULTS

Over two years, 244 women were referred to PIPER with PE; 199 (82%) were subsequently transferred in-utero. Severe PE was diagnosed in 146 (73%) women. Overall, 64% presented 'early' (<32 weeks' gestation). Only 6% were ≥37 weeks. All but 2 women <32 weeks were transferred to a tertiary perinatal centre, compared with 39% of women ≥32 weeks. Within 7 days, 153/199 (77%) delivered, 10% remained in-patients and 12.5% were discharged. There were 165 livebirths and 3 stillbirths, with a mean gestational age of 30.7 weeks (SD 3.3 weeks). Twenty-nine women required high dependency or intensive care admission. No maternal deaths were reported.

CONCLUSION

Women referred to PIPER predominantly presented with early onset, severe PE and most delivered within 7 days of transfer. Data from this study provides important information for obstetric service planning in Victoria and comparable regions.

Neurodevelopmental Outcomes of Infants Born at <29 Weeks of Gestation Admitted to Canadian Neonatal Intensive Care Units Based on Location of Birth

OBJECTIVE

To compare mortality and neurodevelopmental outcomes of outborn and inborn preterm infants born at <29 weeks of gestation admitted to Canadian neonatal intensive care units (NICUs).

STUDY DESIGN

Data were obtained from the Canadian Neonatal Network and Canadian Neonatal Follow-up Network databases for infants born at <29 weeks of gestation admitted to NICUs from April 2009 to September 2011. Rates of death, severe neurodevelopmental impairment (NDI), and overall NDI were compared between outborn and inborn infants at 18-21 months of age, corrected for prematurity.

RESULTS

Of 2951 eligible infants, 473 (16%) were outborn. Mean birth weight (940 ± 278 g vs 897 + 237 g), rates of treatment with antenatal steroids (53.9% vs 92.9%), birth weight small for gestational age (5.3% vs 9.4%), and maternal college education (43.7% vs 53.9%) differed between outborn and inborn infants, respectively (all P values <.01). The median Score for Neonatal Acute Physiology-II (P = .01) and Apgar score at 5 minutes (P < .01) were higher in inborn infants. Severe brain injury was more common among outborn infants (25.3% vs 14.7%, P < .01). Outborn infants had higher odds of death or severe NDI (aOR 1.7, 95% CI 1.3-2.2), death or overall NDI (aOR 1.6, 95% CI 1.2-2.2), death (aOR 2.1, 95% CI 1.5-3.0), and cerebral palsy (aOR 1.9, 95% CI 1.1-3.3).

CONCLUSIONS

The composite outcomes of death or neurodevelopmental impairment were significantly higher in outborn compared with inborn infants admitted to Canadian NICUs. Adverse outcomes were mainly attributed to increased mortality and cerebral palsy in outborn neonates.

Towards evidence-based resuscitation of the newborn infant

Effective resuscitation of the newborn infant has the potential to save many lives around the world and reduce disabilities in children who survive peripartum asphyxia. In this Series paper, we highlight some of the important advances in the understanding of how best to resuscitate newborn infants, which includes monitoring techniques to guide resuscitative efforts, increasing awareness of the adverse effects of hyperoxia, delayed umbilical cord clamping, the avoidance of routine endotracheal intubation for extremely preterm infants, and therapeutic hypothermia for hypoxic-ischaemic encephalopathy. Despite the challenges of performing high-quality clinical research in the delivery room, researchers continue to refine and advance our knowledge of effective resuscitation of newborn infants through scientific experiments and clinical trials.

Outcomes of infants born at 22-27 weeks' gestation in Victoria according to outborn/inborn birth status

OBJECTIVES

To compare mortality and serious morbidity rates between outborn and inborn livebirths at 22-27 weeks' gestation.

DESIGN

Population-based cohort study.

SETTING

Victoria, Australia.

PATIENTS

Livebirths at 22-27 weeks' gestation free of major malformations in 2010-2011.

INTERVENTIONS

Outcome data for outborn (born outside a tertiary perinatal centre) infants compared with inborn (born in a tertiary perinatal centre) infants were analysed by logistic regression, adjusted for gestational age, birth weight and sex.

MAIN OUTCOME MEASURES

Infant mortality and serious morbidity rates to hospital discharge.

RESULTS

541 livebirths free of major malformations were recorded. By 1 year, 49 (58%) outborns and 140 (31%) inborns died (adjusted OR (aOR) 2.78, 95% CI 1.52 to 5.09, p=0.001). In total, 445 infants were admitted to neonatal intensive care unit (NICU); 93 died by 1 year (14/49 outborns and 79/396 inborns), (aOR 1.75, 95% CI 0.87 to 3.55, p=0.12). There were no significant differences in rates of necrotising enterocolitis, intraventricular haemorrhage, retinopathy of prematurity, bronchopulmonary dysplasia (BPD) or the combined outcome of death or BPD in outborn infants compared with inborn infants. Outborns had an increased risk of cystic periventricular leukomalacia (cPVL) compared with inborns (12.2% vs 2.8%, respectively; aOR 5.34, 95% CI 1.84 to 15.54, p=0.002).

CONCLUSIONS

Mortality rates remained higher for outborn livebirths at 22-27 weeks' gestation compared with inborn peers in 2010-2011. Outborn infants admitted to NICU did not have substantially different rates of mortality or serious morbidity compared with inborns, with the exception of cPVL. Longer-term health consequences of outborn birth before 28 weeks' gestation need to be determined.

Outcome of outborn infants at the borderline of viability in Western Australia: A retrospective cohort study

AIM

Preterm infants have a high risk of morbidity and mortality, which increases with decreasing gestational age. Inborn infants (infants born in tertiary perinatal centres) have higher survival and lower morbidity than outborn infants. We aimed to compare short-term and 1-year developmental outcomes of outborn infants at the borderline of viability (≥23 to ≤25 + 6 weeks gestation) with a similar cohort of inborn infants in the sole tertiary perinatal centre in Western Australia from 2001 to 2011.

METHODS

This was a retrospective cohort study. Outborn infants ≥23 to ≤25 + 6 weeks gestation who survived to be transported to the Neonatal Intensive Care Unit (NICU) in the perinatal centre were contemporaneously matched to the next inborn infant of comparable gestation and birth weight. We compared mortality, morbidity (including intraventricular haemorrhage, necrotising enterocolitis and chronic lung disease) and Griffiths General Quotient scores at 1-year corrected age.

RESULTS

There were 54 outborn and 519 inborn births in the gestational age range during the study period. Thirty-five (65%) outborn infants were transported to the NICU. Of the outborn infants, 21/54 (39%) survived to discharge compared with 375/519 (72%) inborn infants. For the 35 outborn infants transported to NICU, 14 (40%) died, compared with 6/35 (17%) of inborn infants. There were no differences in short-term and developmental outcomes in surviving infants.

CONCLUSIONS

Outborn extremely preterm infants <26 weeks gestation have higher mortality than inborn counterparts. However, those transported to a tertiary NICU have similar morbidity and developmental outcomes.