OBJECTIVES: To explore international differences in the classification of births at extremely low gestation and the subsequent impact on the calculation of survival rates.

METHODS: We used national data on births at 22 to 25 weeks' gestation from the United States (2014; n = 11144), Canada (2009-2014; n = 5668), the United Kingdom (2014-2015; n = 2992), Norway (2010-2014; n = 409), Finland (2010-2015; n = 348), Sweden (2011-2014; n = 489), and Japan (2014-2015; n = 2288) to compare neonatal survival rates using different denominators: all births, births alive at the onset of labor, live births, live births surviving to 1 hour, and live births surviving to 24 hours.

RESULTS: For births at 22 weeks' gestation, neonatal survival rates for which we used live births as the denominator varied from 3.7% to 56.7% among the 7 countries. This variation decreased when the denominator was changed to include stillbirths (ie, all births [1.8%-22.3%] and fetuses alive at the onset of labor [3.7%-38.2%]) or exclude early deaths and limited to births surviving at least 12 hours (50.0%-77.8%). Similar trends were seen for infants born at 23 weeks' gestation. Variation diminished considerably at 24 and 25 weeks' gestation.

CONCLUSIONS: International variation in neonatal survival rates at 22 to 23 weeks' gestation diminished considerably when including stillbirths in the denominator, revealing the variation arises in part from differences in the proportion of births reported as live births, which itself is closely connected to the provision of active care.

IMPORTANCE: Diabetes in pregnancy is associated with a 2-times to 3-times higher rate of very preterm birth than in women without diabetes. Very preterm infants are at high risk of death and severe morbidity. The association of maternal diabetes with these risks is unclear.

OBJECTIVE: To determine the associations between maternal diabetes and in-hospital mortality, as well as neonatal morbidity in very preterm infants with a birth weight of less than 1500 g.

DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study was conducted at 7 national networks in high-income countries that are part of the International Neonatal Network for Evaluating Outcomes in Neonates and used prospectively collected data on 76 360 very preterm, singleton infants without malformations born between January 1, 2007, and December 31, 2015, at 24 to 31 weeks' gestation with birth weights of less than 1500 g, 3280 (4.3%) of whom were born to diabetic mothers. EXPOSURES Any type of diabetes during pregnancy.

MAIN OUTCOMES AND MEASURES: The primary outcome was in-hospital mortality. The secondary outcomes were severe neonatal morbidities, including intraventricular hemorrhages of grade 3 to 4, cystic periventricular leukomalacia, retinopathy of prematurity needing treatment and bronchopulmonary dysplasia, and other morbidities, including respiratory distress, treated patent ductus arteriosus, and necrotizing enterocolitis. Odds ratios (ORs) with 95% confidence intervals were estimated, adjusted for potential confounders, and stratified by gestational age (GA), sex, and network.

RESULTS: The mean (SD) birth weight of offspring born to mothers with diabetes was significantly higher at 1081 (262) g than in offspring born to mothers without diabetes (mean [SD] birth weight, 1027 [270] g). Of 76 360 infants, 25 962 (34%) and 33 598 (44%) were born before 28 weeks of gestation to mothers with and without diabetes, respectively. Mothers with diabetes were older and had more hypertensive disorders, antenatal steroid treatments, and deliveries by cesarean delivery than mothers without diabetes. Infants of mothers with diabetes were born at a later GA than infants of mothers without diabetes. In-hospital mortality (6.6% vs 8.3%) and the composite of mortality and severe morbidity (31.6% vs 40.6%) were lower in infants of mothers with diabetes. However, in adjusted analyses, no significant differences in in-hospital mortality (adjusted OR, 1.16 (95% CI, 0.97-1.39) or the composite of mortality and severe morbidity (adjusted OR, 0.99 (95% CI, 0.88-1.10) were observed. With few exceptions, outcomes of infants born to mothers with and without diabetes were similar regardless of infant sex, GA, or country of birth.

CONCLUSIONS AND RELEVANCE: In high-resource settings, maternal diabetes is not associated with an increased risk of in-hospital mortality or severe morbidity in very preterm infants with a birth weight of fewer than 1500 g.

BACKGROUND: Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a rare condition, with an estimated incidence of one in 1000 to 2000 live births. Predominantly, FNAIT is due to maternal alloantibodies that target paternally derived human platelet antigen (HPA) 1a. The most feared complication is an intracranial hemorrhage (ICH). The aim of this study was to determine the frequency of associated maternal platelet (PLT) alloimmunization in a population of neonates born from 32 weeks of gestation and diagnosed with an ICH.

STUDY DESIGN AND METHODS: The Swedish Neonatal Quality (SNQ) register was used to identify neonates diagnosed with an ICH born between 2003 and 2012. Mothers were invited to donate peripheral blood, to investigate their HPA-1a antigen status, and test for anti-HPA and anti-HLA Class I alloantibodies. Clinical data for the neonates were retrieved from the SNQ register and available clinical records.

RESULTS: Of 286 registered neonates, 278 mothers were contacted. Of 105 analyzed maternal samples, two (1.9%) were HPA-1a antigen negative. Antibody analyses revealed in total three (2.9%) mothers with anti-HPA: one mother (0.94%) with anti-HPA-1a and two mothers (1.9%) with anti-HPA-5b, of whom one had concurrent anti-HPA-15a. Twenty-four percent tested positive for anti-HLA Class I antibodies. A total of 8.5% of neonates (5/59) with PLT counts available in clinical records were severely thrombocytopenic, with PLT counts of less than 50 × 109/L.

CONCLUSIONS: This retrospective cohort revealed a wide range of factors associated with ICH in neonates born from 32 weeks of gestation and suggests PLT alloimmunization to be a less common contributor than anticipated.

Background: Compared to very low gestational age (<32 weeks, VLGA) cohorts, very low birth weight (<1500 g; VLBW) cohorts are more prone to selection bias toward small-for-gestational age (SGA) infants, which may impact upon the validity of data for benchmarking purposes. Method: Data from all VLGA or VLBW infants admitted in the 3 Networks between 2008 and 2011 were used. Two-thirds of each network cohort was randomly selected to develop prediction models for mortality and composite adverse outcome (CAO: mortality or cerebral injuries, chronic lung disease, severe retinopathy or necrotizing enterocolitis) and the remaining for internal validation. Areas under the ROC curves (AUC) of themodels were compared. Results: VLBW cohort (24,335 infants) had twice more SGA infants (20.4% vs. 9.3%) than the VLGA cohort (29,180 infants) and had a higher rate of CAO (36.5% vs. 32.6%). The two models had equal prediction power for mortality and CAO (AUC 0.83), and similarly for all other cross-cohort validations (AUC 0.81-0.85). Neither model performed well for the extremes of birth weight for gestation (<1500 g and >= 32 weeks, AUC 0.50-0.65; >= 1500 g and >= 32 weeks, AUC 0.60-0.62). Conclusion: There was no difference in prediction power for adverse outcome between cohorting VLGA or VLBW despite substantial bias in SGA population. Either cohorting practises are suitable for international benchmarking.

OBJECTIVE: To compare the rates of retinopathy of prematurity (ROP) and treatment of ROP by laser or intravitreal anti-vascular endothelial growth factor among preterm neonates from high-income countries participating in the International Network for Evaluating Outcomes (iNeo) of neonates.

METHODS: weeks' gestation who were admitted to neonatal units in Australia/New Zealand, Canada, Finland, Israel, Japan, Spain, Sweden, Switzerland, Tuscany (Italy) and the UK between 2007 and 2013. Pairwise comparisons of ROP treatment in survivors between countries were evaluated by Poisson and multivariable logistic regression analyses after adjustment for confounders. A composite outcome of death or ROP treatment was compared between countries using logistic regression and standardised ratios.

RESULTS: Of 48 087 infants included in the analysis, 81.8% survived to 32 weeks postmenstrual age, and 95% of survivors were screened for ROP. Rates of any ROP ranged from 25.2% to 91.0% in Switzerland and Japan, respectively, among those examined. The overall rate of those receiving treatment was 24.9%, which varied from 4.3% to 30.4%. Adjusted risk ratios for ROP treatment were lower for Switzerland in all pairwise comparisons, whereas Japan displayed significantly higher ratios. Comparisons of the composite outcome between countries revealed similar, but less marked differences.

CONCLUSIONS: Rates of any ROP and ROP treatment varied significantly between iNeo members, while an overall decline in ROP treatment was observed during the study period. It is unclear whether these variations represent differences in care practices, diagnosis and/or treatment thresholds.

OBJECTIVE: To explore population characteristics, organization of health services and comparability of available information for very low birth weight or very preterm neonates born before 32 weeks' gestation in 11 high-income countries contributing data to the International Network for Evaluating Outcomes of Neonates (iNeo).

STUDY DESIGN: We obtained population characteristics from public domain sources, conducted a survey of organization of maternal and neonatal health services and evaluated the comparability of data contributed to the iNeo collaboration from Australia, Canada, Finland, Israel, Italy, Japan, New Zealand, Spain, Sweden, Switzerland and UK.

RESULTS: All countries have nationally funded maternal/neonatal health care with >90% of women receiving prenatal care. Preterm birth rate, maternal age, and neonatal and infant mortality rates were relatively similar across countries. Most (50 to >95%) between-hospital transports of neonates born at non-tertiary units were conducted by designated transport teams; 72% (8/11 countries) had designated transfer and 63% (7/11 countries) mandate the presence of a physician. The capacity of 'step-down' units varied between countries, with capacity for respiratory care available in <10% to >75% of units. Heterogeneity in data collection processes for benchmarking and quality improvement activities were identified.

CONCLUSIONS: Comparability of healthcare outcomes for very preterm low birth weight neonates between countries requires an evaluation of differences in population coverage, healthcare services and meta-data.

IntroductionThis study aimed to investigate the incidence of neonatal early-onset group B streptococcal (GBS) infection in Sweden after promulgation of guidelines (2008) for risk factor-based intrapartum antibiotic prophylaxis, and evaluate the presence of risk factors and obstetric management in mothers. Material and methodsNational registers were searched for infants with early-onset GBS infection during 2006-2011. Medical records of cases and case mothers were abstracted. Verified cases of sepsis/meningitis and cases with clinical sepsis/pneumonia were documented, as well as risk factors in case mothers and timeliness of intrapartum antibiotic prophylaxis administration. ResultsThere were 227 cases with verified infection, with an incidence of 0.34 of live births during the whole period. There was a significant decrease after promulgation of guidelines, from 0.40 to 0.30 parts per thousand [odds ratio (OR) 0.75, 95% confidence interval (CI) 0.57-0.99]. A significant decrease in the number of cases with clinical GBS sepsis/pneumonia was also observed. In parturients with one or more risk factors, the incidence of any GBS infection was reduced by approximately 50% (OR 0.47, 95% CI 0.35-0.64), although there were many cases where the opportunity for timely administration of intrapartum antibiotic prophylaxis was missed. In infants of mothers without risk factor(s) there was no reduction in early-onset GBS morbidity. The mortality in verified cases was 4.8% (95% CI 2.1-7.6). ConclusionsThe introduction of national guidelines for risk-based intrapartum antibiotic prophylaxis coincided with a significant 50% risk reduction of neonatal early-onset GBS infection in infants of parturients presenting with one or more risk factors. A stricter adherence to guidelines could probably have reduced the infant morbidity further.

The use of different definitions for bronchopulmonary dysplasia (BPD) has been an ongoing challenge. We searched papers published in English from 2010 and 2015 reporting BPD as an outcome, together with studies that compared BPD definitions between 1978 and 2015. We found that the incidence of BPD ranged from 6% to 57%, depending on the definition chosen, and that studies that investigated correlations with long-term pulmonary and/or neurosensory outcomes reported moderate-to-low predictive values regardless of the BPD criteria.

CONCLUSION: A comprehensive and evidence-based definition for BPD needs to be developed for benchmarking and prognostic use.

OBJECTIVES: To compare survival rates and age at death among very preterm infants in 10 national and regional neonatal networks.

METHODS: A cohort study of very preterm infants, born between 24 and 29 weeks' gestation and weighing <1500 g, admitted to participating neonatal units between 2007 and 2013 in the International Network for Evaluating Outcomes of Neonates. Survival was compared by using standardized ratios (SRs) comparing survival in each network to the survival estimate of the whole population.

RESULTS: Network populations differed with respect to rates of cesarean birth, exposure to antenatal steroids and birth in nontertiary hospitals. Network SRs for survival were highest in Japan (SR: 1.10; 99% confidence interval: 1.08-1.13) and lowest in Spain (SR: 0.88; 99% confidence interval: 0.85-0.90). The overall survival differed from 78% to 93% among networks, the difference being highest at 24 weeks' gestation (range 35%-84%). Survival rates increased and differences between networks diminished with increasing gestational age (GA) (range 92%-98% at 29 weeks' gestation); yet, relative differences in survival followed a similar pattern at all GAs. The median age at death varied from 4 days to 13 days across networks.

CONCLUSIONS: The network ranking of survival rates for very preterm infants remained largely unchanged as GA increased; however, survival rates showed marked variations at lower GAs. The median age at death also varied among networks. These findings warrant further assessment of the representativeness of the study populations, organization of perinatal services, national guidelines, philosophy of care at extreme GAs, and resources used for decision-making.

BACKGROUND: Controversy exists as to whether birthweight-for-gestational age references used to classify infants as small for gestational age (SGA) should be country specific or based on an international (common) standard. We examined whether different birthweight-for-gestational age references affected the association of SGA with adverse outcomes among very preterm neonates.

METHODS: Singleton infants (n = 23 788) of 24(0) -28(6) weeks' gestational age in nine high-resource countries were classified as SGA (<10th centile) using common and country-specific references based on birthweight and estimated fetal weight (EFW). For each reference, the adjusted relative risk (aRR) for the association of SGA with composite outcome of mortality or major morbidity was estimated.

RESULTS: The percentage of infants classified as SGA differed slightly for common compared with country specific for birthweight references [9.9% (95% CI 9.5, 10.2) vs. 11.1% (95% CI 10.7, 11.5)] and for EFW references [28.6% (95% CI 28.0, 29.2) vs. 24.6% (95% CI 24.1, 25.2)]. The association of SGA with the composite outcome was similar when using common or country-specific references for the total sample for birthweight [aRRs 1.47 (95% CI 1.43, 1.51) and 1.48 (95% CI 1.44, 1.53) respectively] and for EFW references [aRRs 1.35 (95% CI 1.31, 1.38) and 1.39 (95% CI 1.35, 1.43) respectively].

CONCLUSION: Small for gestational age is associated with higher mortality and morbidity in infants born <29 weeks' gestational age. Although common and country-specific birthweight/EFW references identified slightly different proportions of SGA infants, the risk of the composite outcome was comparable.