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Aim: We evaluated the increased centralisation of extremely preterm (EPT) births in Sweden in relation to the changes in mortality and morbidity.

Methods: Population-based data covering Swedish live births from 22 + 0 to 26 + 6 weeks of gestation during 2004–2007 and 2014–2016 were analysed for associations between time-period, birth within (inborn) or outside (outborn) regional centres, and outcomes.

Results: Among 1626 liveborn infants, 703 were born in 2004–2007 and 923 in 2014–2016. Birth outside (vs. within) regional centres was associated with a higher infant mortality even after adjustment for birth cohort, gestational age, birthweight standard deviation score and infant sex (adjusted odds ratio 2.01, 95% confidence interval 1.31–3.07, p = 0.001). The higher 1-year mortality in outborn infants was mainly due to more deaths within 24 h after birth. Outborn infants had a higher incidence of intraventricular haemorrhage grade 3–4 than inborn infants (22% vs. 14% in 2004–2007, and 22% vs. 13% in 2014–2016, both p < 0.05). While survival to 1 year without major morbidity increased in inborn infants (33%–40%, p = 0.008), it remained unchanged in outborn infants (29% vs. 30%, p = 0.88).

Conclusion: Centralisation of EPT births contributed to a lower 1-year mortality in 2014–2016 than that in 2004–2007, attributed to a decrease in deaths before 24 h among inborn infants.

Studies on pain in preterm infants have usually been confined to observations of painful procedures, and information from extremely preterm infants is limited. Using registry data from a Swedish nationwide cohort, this study explored the epidemiology of pain in very preterm infants, its causes, assessments, and treatment strategies. We included liveborn infants <32 weeks' gestational age (GA) discharged between January 2020 and June 2024. Proportions of infants exposed to potentially painful procedures, experiencing pain, assessed with pain scales, and receiving pharmacological treatment were calculated by each postnatal day. Among 3686 infants (mean birthweight 1176 g, GA 28.2 weeks), 11.6% had a painful condition and 84.1% were exposed to at least 1 potentially painful procedure. In total, 74.6% experienced pain, corresponding to 28,137/185,008 (15.2%) days of neonatal care. For every 2-week increase in GA, significantly lower proportions of infants experienced pain. In infants <28 weeks of GA, proportions with reported pain were approximately half the rate of painful procedures, while in infants born at 28 to 31 weeks, reported pain closely matched exposure to painful procedures. Pain scales were used in 75.0% of the infants. Pharmacological pain treatment was administered to 81.7% of infants, primarily topically or orally. Among infants with pain, proportions treated intravenously were larger at higher GAs. Despite effective analgesia/anesthesia, many very preterm infants experience pain. Visualizing pain epidemiology, procedures, conditions, and treatment by postnatal and gestational age may guide clinical management and generate research hypotheses to reduce short- and long-term adverse effects.

Background: Our aim was to evaluate if increased survival and new ventilation strategies were accompanied by a changed incidence of bronchopulmonary dysplasia (BPD) in Sweden over a decade.

Methods: Data from two Swedish population-based studies of live-born infants with gestational age (GA) 22–26 weeks, born during 2004–2007 (n=702) and 2014–2016 (n=885), were compared for survival, any BPD, moderate BPD and severe BPD and the composite outcomes of any BPD or death and severe BPD or death at 36 weeks postmenstrual age (PMA). Ventilation strategies and interventions were analysed. Any BPD was defined as the use of supplemental oxygen or any respiratory support at 36 weeks PMA, moderate BPD as nasal cannula with <30% oxygen and severe BPD as ≽30% oxygen, continuous positive airway pressure (CPAP) or mechanical ventilation.

Results: Survival to 36 weeks PMA increased from 72% to 81% (p<0.001). Total days on mechanical ventilation increased from a median of 9 to 16 days (p<0.001). High-flow nasal cannula (HFNC) was introduced between the cohorts, and days of CPAP and HFNC increased from 44 to 50 days (p<0.001). Any BPD was unchanged at 65% versus 68%. Moderate BPD increased from 37% to 47% (p=0.003), while the incidence of severe BPD decreased from 28% to 23% (p<0.046). Severe BPD or death decreased from 48% to 37% (p<0.001), while any BPD or death remained unchanged at 74% versus 75%.

Conclusion: Even though an increased survival of infants born at 22–26 weeks GA was accompanied by an increased duration of invasive and non-invasive respiratory support, the incidence of any BPD remained unchanged, while severe BPD decreased in infants alive at 36 weeks PMA.

Background: Neonatal early-onset disease caused by group B Streptococcus (GBS) is a leading cause of infant morbidity. Intrapartum antibiotic prophylaxis (IAP) is effective in preventing early-onset GBS disease, but there is no agreement on the optimal strategy for identifying the pregnant women requiring this treatment, and both risk-based prophylaxis (RBP) and GBS screening-based prophylaxis (SBP) are used.

Aim: The aim of this study was to evaluate the effect of SBP as a public health intervention on the epidemiology of early-onset GBS infections.

Methods: In 2012, Finland started the universal SBP, while Denmark, Iceland, Norway and Sweden continued with RBP. We conducted an interrupted time series analysis taking 2012 as the intervention point to evaluate the impact of this intervention. The incidences of early- and late-onset GBS infections during Period I (1995-2011) and Period II (2012-2019) were collected from each national register, covering 6,605,564 live births.

Results: In Finland, a reduction of 58% in the incidence of early-onset GBS disease, corresponding to an incidence rate ratio (IRR) of 0.42 (95% CI: 0.34-0.52), was observed after 2012. At the same time, the pooled IRR of other Nordic countries was 0.89 (95% CI: 0.80-1.0), specifically 0.89 (95% CI: 0.70-1.5) in Denmark, 0.34 (95% CI: 0.15-0.81) in Iceland, 0.72 (95% CI: 0.59-0.88) in Norway and 0.97 (95% CI: 0.85-1.1) in Sweden.

Conclusions: In this ecological study of five Nordic countries, early-onset GBS infections were approximately halved following introduction of the SBP approach as compared with RBP.

OBJECTIVE: To investigate potential risk factors behind the increased incidence of necrotising enterocolitis (NEC) in Swedish extremely preterm infants.

DESIGN: Registry data from two population-based national cohorts were studied. NEC diagnoses (Bell stage ≥II) were validated against hospital records.

PATIENTS: All liveborn infants <27 weeks of gestation 2004-2007 (n=704) and 2014-2016 (n=895) in Sweden.

MAIN OUTCOME MEASURES: NEC incidence.

RESULTS: The validation process resulted in a 28% reduction of NEC cases but still confirmed a higher NEC incidence in the later epoch compared with the earlier (73/895 (8.2%) vs 27/704 (3.8%), p=0.001), while the composite of NEC or death was lower (244/895 (27.3%) vs 229/704 (32.5%), p=0.022). In a multivariable Cox regression model, censored for mortality, there was no significant difference in early NEC (0-7 days of life) between epochs (HR=0.9 (95% CI 0.5 to 1.9), p=0.9), but being born in the later epoch remained an independent risk factor for late NEC (>7 days) (HR=2.7 (95% CI 1.5 to 5.0), p=0.001). In propensity score analysis, a significant epoch difference in NEC incidence (12% vs 2.8%, p<0.001) was observed only in the tertile of infants at highest risk of NEC, where the 28-day mortality was lower in the later epoch (35% vs 50%, p=0.001). More NEC cases were diagnosed with intramural gas in the later epoch (33/73 (45.2%) vs 6/26 (23.1%), p=0.047).

CONCLUSIONS: The increase in NEC incidence between epochs was limited to cases occurring after 7 days of life and was partly explained by increased survival in the most extremely preterm infants. Misclassification of NEC is common.

Introduction: Despite advances in neonatal care, late-onset sepsis remains an important cause of preventable morbidity and mortality. Neonatal late-onset sepsis rates have decreased in some countries, while in others they have not. Our objective was to compare trends in late-onset sepsis rates in 9 population-based networks from 10 countries and to assess the associated mortality within 7 days of late-onset sepsis.

Methods: We performed a retrospective populationbased cohort study. Infants born at 24-28 weeks' gestation between 2007 and 2019 were eligible for inclusion. Lateonset sepsis was defined as a positive blood or cerebrospinal fluid culture. Late-onset sepsis rates were calculated for 3 epochs (2007-11, 2012-15, and 2016-19). Adjusted risk ratios (aRRs) for late-onset sepsis were calculated for each network.

Results: Of a total of 82,850 infants, 16,914 (20.4%) had late-onset sepsis, with Japan having the lowest rate (7.1%) and Spain the highest (44.6%). Late-onset sepsis rates decreased in most networks and remained unchanged in a few. Israel, Sweden, and Finland showed the largest decrease in late-onset sepsis rates. The aRRs for late-onset sepsis showed wide variations between networks. The rate of mortality temporally related to late-onset sepsis was 10.9%. The adjusted mean length of stay for infants with late-onset sepsis was increased by 5-18 days compared to infants with no late-onset sepsis.

Conclusions: One in 5 neonates of 24-28 weeks' gestation develops late-onset sepsis. Wide variability in late-onset sepsis rates exists between networks with most networks exhibiting improvement. Late-onset sepsis was associated with increased mortality and length of stay.

Objective: To explore associations between perinatal activity and survival in infants born at 22 and 23 weeks of gestation in Sweden.

Design/Setting: Data on all births at 22 and 23 weeks' gestational age (GA) were prospectively collected in 2004-2007 (T1) or obtained from national registers in 2014-2016 (T2) and 2017-2019 (T3). Infants were assigned perinatal activity scores based on 3 key obstetric and 4 neonatal interventions.

Main outcome: One-year survival and survival without major neonatal morbidities (MNM): intraventricular haemorrhage grade 3-4, cystic periventricular leucomalacia, surgical necrotising enterocolitis, retinopathy of prematurity stage 3-5 or severe bronchopulmonary dysplasia. The association of GA-specific perinatal activity score and 1-year survival was also determined.

Results: 977 infants (567 live births and 410 stillbirths) were included: 323 born in T1, 347 in T2 and 307 in T3. Among live-born infants, survival at 22 weeks was 5/49 (10%) in T1 and rose significantly to 29/74 (39%) in T2 and 31/80 (39%) in T3. Survival was not significantly different between epochs at 23 weeks (53%, 61% and 67%). Among survivors, the proportions without MNM in T1, T2 and T3 were 20%, 17% and 19% for 22 weeks and 17%, 25% and 25% for 23 weeks' infants (p>0.05 for all comparisons). Each 5-point increment in GA-specific perinatal activity score increased the odds for survival in first 12 hours of life (adjusted OR (aOR) 1.4; 95% CI 1.3 to 1.6) in addition to 1-year survival (aOR 1.2; 95% CI 1.1 to 1.3), and among live-born infants it was associated with increased survival without MNM (aOR 1.3; 95% CI 1.1 to 1.4).

Conclusion: Increased perinatal activity was associated with reduced mortality and increased chances of survival without MNM in infants born at 22 and 23 weeks of GA.

Introduction: A detailed understanding of respiratory support patterns in preterm infants is lacking. The aim was to explore and visualize this practice in Sweden.

Methods: Preterm infants with gestational ages of 22-31 weeks, admitted to neonatal units reporting daily to the Swedish Neonatal Quality Register and discharged alive in November 2015-April 2022, were included in this descriptive cohort study. Proportions receiving mechanical ventilation, noninvasive support, or supplemental oxygen were calculated and graphically displayed for each gestational week and postnatal day (range 0-97) up to hospital discharge or 36 weeks of postmenstrual age.

Results: Respiratory support in 148,515 days of care (3,368 infants; 54% males; median [interquartile range] birthweight = 1,215 [900-1,525] g) was evaluated. Trajectories showed distinct nonlinear patterns for each category of respiratory support, but differences in respiratory support over the gestational age range were linear: the proportion of infants on mechanical ventilation decreased by -11.7 to -7.3% (variability in estimates related to the postnatal day chosen for regression analysis) for each week higher gestational age (r = -0.99 to -0.87, p ≤ 0.001). The corresponding proportions of infants with supplemental oxygen decreased by -12.4% to -4.5% for each week higher gestational age (r = -0.98 to -0.94, p < 0.001). At 36 weeks of postmenstrual age, dependencies on mechanical ventilation, noninvasive support, and supplemental oxygen varied from 3%, 84%, and 94% at 22 weeks to 0%, 3%, and 5% at 31 weeks of gestational age, respectively.

Conclusions: Respiratory support patterns in very preterm infants follow nonlinear, gestational age-specific postnatal trajectories in a dose-response-related fashion.

Aim: Organisation of care, perinatal and neonatal management of very preterm infants in the Nordic regions were hypothesised to vary significantly. The aim of this observational study was to test this hypothesis.

Methods: Information on preterm infants in the 21 greater healthcare regions of Denmark, Finland, Iceland, Norway and Sweden was gathered from national registers in 2021. Preterm birth rates, case-mix, perinatal interventions, neonatal morbidity and survival to hospital discharge in very (<32 weeks) and extremely preterm infants (<28 weeks of gestational age) were compared.

Results: Out of 287 642 infants born alive, 16 567 (5.8%) were preterm, 2389 (0.83%) very preterm and 800 (0.28%) were extremely preterm. In very preterm infants, exposure to antenatal corticosteroids varied from 85% to 98%, live births occurring at regional centres from 48% to 100%, surfactant treatment from 28% to 69% and use of mechanical ventilation varied from 13% to 77% (p < 0.05 for all comparisons). Significant regional variations within and between countries were also seen in capacity in neonatal care, case-mix and number of admissions, whereas there were no statistically significant differences in survival or major neonatal morbidities.

Conclusion: Management of very preterm infants exhibited significant regional variations in the Nordic countries.

A vision for Swedish neonatal care is that all newborn infants receive the care they need, when they need it, that the experience is excellent for all families, and that neonatal care is executed by the highest quality and safety standards. To support this vision, the Swedish Neonatal Quality Register (SNQ) was founded with a mission to provide stake holders, professionals and the public with data and knowledge that would stimulate quality improvement (QI), research and development in neonatal care. SNQ covers all infants admitted to all 37 neonatal units (level I–III) serving the approximately 115,000 annual births in Sweden. Quality indicators include capacity and availability (number of beds, staffing, equipment), process (interventions) and outcome (survival and morbidity) measures for medical as well as nursing care. To better understand how neonatal care is associated with long-term outcome, the results of a national follow-up program at 2- and 5½-year-of-age are also reported to SNQ. In addition, parental experiences of neonatal care have recently become an integrated part of the database. SNQ’s completeness and validity, especially for preterm infants, has been found to be excellent. SNQ is therefore used as a tool for benchmarking over time and between unit and regions. Robust data from more than 230,000 neonatal admissions are available. Besides stimulating a continuously increasing number of clinical research projects, the data from SNQ has been found useful by Swedish authorities, professional and stakeholder organizations, local hospital administrations, teachers, as well as by the attending team in the neonatal unit. The most recent development with daily data collection in >95% of all admissions opens for new and more dynamic insights into the course of several neonatal conditions, as well as for timely outreach of results.