Intrauterine inflammation as a risk factor for persistent ductus arteriosus patency after cyclooxygenase inhibition in extremely low birth weight infants

Effect of Maternal Coronavirus Disease on Preterm Morbidities

OBJECTIVE

 Coronavirus disease (COVID-19) during pregnancy may have an impact on preterm morbidities due to the inflammatory nature of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Exposure to intrauterine inflammation could result in adverse consequences in preterm infants. We aimed to determine the effect of maternal coronavirus disease on preterm morbidities at a tertiary neonatal intensive care unit.

STUDY DESIGN

 This observational cohort study compared the clinical outcomes of preterm infants < 37 gestational weeks with and without maternal COVID-19. The study was conducted in a tertiary-level neonatal intensive care unit between March 2020 and December 2021. Demographics and clinical data of the study groups were collected from the medical files.

RESULTS

 A total of 254 infants (127 in the maternal COVID-19 group and 127 in the control group) were included in the study. Respiratory distress syndrome, early and late neonatal sepsis, intraventricular hemorrhage, patent ductus arteriosus (PDA), necrotizing enterocolitis, bronchopulmonary dysplasia, and retinopathy of prematurity rates were similar between groups. In the subgroup analysis, the rate of PDA was significantly higher in preterm infants ≤1,500 g with maternal SARS-CoV-2 infection (38 vs. 15% p = 0.023). Presence of maternal COVID-19 was found to be an independent predictor for PDA in very low birthweight infants, as revealed by multivariate analyses (odds ratio: 3.4; 95% confidence interval: 1.12-10.4; p = 0.031). Mortality rates and duration of hospitalization were similar in both groups.

CONCLUSION

 Our results suggest that COVID-19 infection during pregnancy seems to have no adverse effect on preterm morbidities and mortality. However, maternal COVID-19 was found to be a risk factor for PDA in preterm infants ≤1,500 g.

KEY POINTS

· The effect of maternal COVID-19 on preterm morbidities still has not well defined.. · Maternal COVID-19 seems to have no adverse effect on preterm morbidities and mortality.. · The exact impact of the COVID-19 on fetal/neonatal health is yet to be clarified..

Increasing the dose of ibuprofen with postnatal age to close a hemodynamically significant patent ductus arteriosus in very preterm infants

Patent ductus arteriosus (PDA) is associated with neonatal morbidities in high-risk preterm infants. Early neonatal treatment by ibuprofen induces the ductus arteriosus (DA) closure in approximatively 60% of infants. Dose escalation of ibuprofen according to postnatal age has been suggested for improving the DA closure rate. The aim of this study was to assess the efficacy and tolerance of an increasing dose regimen of ibuprofen. This single-center retrospective cohort study involved infants hospitalized from 2014 to 2019 in our neonatal unit. Selection criteria were gestational age < 30 weeks, birth weight < 1000 g, and treatment by ibuprofen. Three dose levels were used and consisted of a daily intravenous injection of ibuprofen-tris-hydroxymethyl-aminomethane (ibuprofen-THAM) for three consecutive days: (i) 10 -5 -5 mg/kg before the 70th h of life (H70) (dose level 1), (ii) 14 -7 -7 mg/kg between H70 and H108 (dose level 2), (iii) 18 -9 -9 mg/kg after H108 (dose level 3). The ibuprofen-induced DA closure was compared between ibuprofen schedules, and the Cox proportional-hazard regression was performed to identify factors associated with the ibuprofen efficacy. Tolerance was assessed through renal function, acidosis, and platelet count. One hundred forty-three infants met the inclusion criteria. The ibuprofen-induced DA closure was observed in 67 infants (46.8%). One course of ibuprofen at dose level 1 was more efficient in closing the DA than other schedules (dose level 1, one course (n = 70): 71%, dose level 2 or 3, one course (n = 20): 45%, two-course schedules (n = 53): 15%, p < 0.0001). Independent factors associated with ibuprofen-induced DA closure were a complete antenatal schedule of steroids (p = 0.001), a lower CRIB II score (p = 0.009), and a lower and earlier exposure to ibuprofen (p < 0.0001 and p = 0.002). No severe side effects were observed. Neonatal mortality and morbidities were similar regardless of the infant's response to ibuprofen.  Conclusion: Increasing ibuprofen doses with postnatal age failed to reach an efficacy similar to earlier treatment. Although the infant response to ibuprofen was likely to depend on multiple factors, the optimal use of ibuprofen included its early initiation. What is Known: • Ibuprofen is the current first-line treatment for patent ductus arteriosus during the early neonatal period in very preterm infants. • However, the ibuprofen efficacy rapidly declined with postnatal age during the first week of life. A dose escalation of ibuprofen according to postnatal age has been suggested to improve the ibuprofen-induced ductus arteriosus closure. What is New: • The rapid drop of ibuprofen's ability to close hemodynamically significant patent ductus arteriosus persisted beyond the postnatal day 2 despite the dose adjustment arguing for an early initiation to optimize its efficacy. • The early selection of patients who will suffer from patent ductus arteriosus-related morbidities and who will positively respond to ibuprofen is an issue that could determine the future place of ibuprofen in the patent ductus arteriosus management.

Association between endotypes of prematurity and pharmacological closure of patent ductus arteriosus: A systematic review and meta-analysis

Introduction

Endotypes leading to very and extremely preterm birth are clustered into two groups: infection/inflammation and dysfunctional placentation. We conducted a systematic review of observational studies exploring the association between these two endotypes and the pharmacological closure of patent ductus arteriosus (PDA) induced by cyclooxygenase (COX) inhibitors. Chorioamnionitis represented the infectious-inflammatory endotype, while dysfunctional placentation proxies were hypertensive disorders of pregnancy (HDP) and small for gestational age (SGA) or intrauterine growth restriction.

Methods

PubMed/Medline and Embase databases were searched. The random-effects odds ratio (OR) and 95% confidence interval (CI) were calculated for each association. We included 30 studies (12,639 infants).

Results

Meta-analysis showed a significant association between exposure to HDP and increased rate of pharmacological closure of PDA (17 studies, OR 1.41, 95% CI 1.10-1.81, p = 0.006). In contrast, neither chorioamnionitis (13 studies, OR 0.75, 95% CI 0.47-1.18, p = 0.211) nor SGA (17 studies, OR 1.20, 95% CI 0.96-1.50, p = 0.115) were significantly associated with the response to therapy. Subgroup analyses showed that the higher response to COX inhibitors in the HDP group was significant for indomethacin (OR 1.568, 95% CI 1.147-2.141, p = 0.005) but not for ibuprofen (OR 1.107, 95% CI 0.248-4.392, p = 0.894) or for the studies using both drugs (OR 1.280, 95% CI 0.935-1.751, p = 0.124). However, meta-regression showed that this difference between the drugs was not statistically significant (p = 0.404).

Discussion/Conclusion

Our data suggest that the pathologic condition that triggers prematurity may alter the response to pharmacological treatment of PDA. The DA of infants exposed to HDP appears to be more responsive to COX inhibitors.

Association of patent ductus arteriosus with fetal factors and endotypes of prematurity

During fetal life, the ductus arteriosus (DA) acquires the mechanisms for its postnatal closure following a thorough developmental program. This program can be interrupted by preterm birth and is also susceptible to alteration during fetal life by numerous physiological and pathological stimuli. In this review, we aim to summarize the evidence on how physiological and pathological factors affect DA development, eventually leading to patent DA (PDA). Specifically, we reviewed the associations of sex, race, and pathophysiological pathways leading to very preterm birth (endotypes) with PDA incidence and pharmacological closure. Summary of evidence suggests that there are no male-female differences in the incidence of PDA among very preterm infants. In contrast, risk of developing PDA appears to be higher in infants exposed to chorioamnionitis or who are small for gestational age. Finally, hypertensive disorders of pregnancy may be associated with a better response to pharmacological treatment of PDA. All of this evidence comes from observational studies and therefore associations do not imply causation. The current trend for many neonatologists is to wait for the natural evolution of preterm PDA. Continued research is needed to identify which fetal and perinatal factors modulate the eventual late closure of PDA in very and extremely preterm infants.

The role of interleukin-1 in perinatal inflammation and its impact on transitional circulation

Preterm birth is defined as delivery at <37 weeks of gestational age (GA) and exposes 15 million infants worldwide to serious early life diseases. Lowering the age of viability to 22 weeks GA entailed provision of intensive care to a greater number of extremely premature infants. Moreover, improved survival, especially at extremes of prematurity, comes with a rising incidence of early life diseases with short- and long-term sequelae. The transition from fetal to neonatal circulation is a substantial and complex physiologic adaptation, which normally happens rapidly and in an orderly sequence. Maternal chorioamnionitis or fetal growth restriction (FGR) are two common causes of preterm birth that are associated with impaired circulatory transition. Among many cytokines contributing to the pathogenesis of chorioamnionitis-related perinatal inflammatory diseases, the potent pro-inflammatory interleukin (IL)-1 has been shown to play a central role. The effects of utero-placental insufficiency-related FGR and in-utero hypoxia may also be mediated, in part, via the inflammatory cascade. In preclinical studies, blocking such inflammation, early and effectively, holds great promise for improving the transition of circulation. In this mini-review, we outline the mechanistic pathways leading to abnormalities in transitional circulation in chorioamnionitis and FGR. In addition, we explore the therapeutic potential of targeting IL-1 and its influence on perinatal transition in the context of chorioamnionitis and FGR.

The Association of Patent Ductus Arteriosus with Inflammation: A Narrative Review of the Role of Inflammatory Biomarkers and Treatment Strategy in Premature Infants

Patent ductus arteriosus (PDA) is a common cardiovascular complication that complicates clinical care in the intensive care of premature infants. Prenatal and postnatal infections and the inflammation process can contribute to PDA, and intrauterine inflammation is a known risk factor of PDA. A variety of inflammatory biomarkers have been reported to be associated with PDA. Chorioamnionitis induces the fetal inflammatory process via several cytokines that have been reported to be associated with the presence of PDA and may have a role in the vascular remodeling process or vessel dilation of the ductus. On the other hand, anti-inflammatory agents, such as antenatal steroids, decrease PDA incidence and severity in patients born to those with chorioamnionitis. Proinflammatory cytokines, which are expressed more significantly in preterm neonates and chorioamnionitis, are associated with the presence of PDA. In this review, we focus on the pathogenesis of PDA in preterm infants and the role of biomarkers associated with the perinatal inflammatory process.

Sex Differences in Patent Ductus Arteriosus Incidence and Response to Pharmacological Treatment in Preterm Infants: A Systematic Review, Meta-Analysis and Meta-Regression

A widely accepted concept in perinatal medicine is that boys are more susceptible than girls to complications of prematurity. However, whether this ‘male disadvantage of prematurity’ also involves persistent patent ductus arteriosus (PDA) has been scarcely investigated. Our aim was to conduct a systematic review and meta-analysis on studies addressing sex differences in the risk of developing PDA among preterm infants. We also investigated whether the response to pharmacological treatment of PDA differs between boys and girls. PubMed/Medline and Embase databases were searched. The random-effects male/female risk ratio (RR) and 95% confidence interval (CI) were calculated. We included 146 studies (357,781 infants). Meta-analysis could not demonstrate sex differences in risk of developing any PDA (37 studies, RR 1.03, 95% CI 0.97 to 1.08), hemodynamically significant PDA (81 studies, RR 1.00, 95% CI 0.97 to 1.02), or in the rate of response to pharmacological treatment (45 studies, RR 1.01, 95% CI 0.98 to 1.04). Subgroup analysis and meta-regression showed that the absence of sex differences was maintained over the years and in different geographic settings. In conclusion, both the incidence of PDA in preterm infants and the response rate to pharmacological treatment of PDA are not different between preterm boys and girls.

Patent ductus arteriosus in preterm newborns: a tertiary hospital experience

INTRODUCTION

Patent ductus arteriosus (PDA) in preterm newborns has been associated with increased mortality and co-morbidities. This study aimed to characterize the population of preterm infants diagnosed with PDA and to identify predictive factors of response to medical treatment of PDA.

METHODS

An eight-year retrospective observational study was conducted, which included all preterm newborns (PTNB) with a gestational age between 23 and 32 weeks diagnosed with PDA, admitted to the Neonatal Unit of the Centro Hospitalar Universitário de São João. Univariate comparative analysis was performed and models for predicting the effectiveness of PDA treatment with ibuprofen were explored by multivariate logistic regression analysis.

RESULTS

115 cases were included in the study and 34 were excluded, with a final sample of 81 PTNB with PDA. The univariate analysis revealed significant differences in the closure efficacy by medical treatment with ibuprofen in several variables, and a multivariate logistic regression model was obtained (discriminative capacity 72.2%, sensitivity 98.1%, specificity 57.1%), considering the effect of gestational age, type of delivery, need for diuretics treatment and platelet transfusion.

CONCLUSION

This study enabled the characterization of the population of preterm infants diagnosed with PDA and the identification of a predictive model that can assist with predicting the effectiveness of the medical treatment and thus contribute to optimizing the medical approach to non-responders.

Molecular Mechanisms Underlying Remodeling of Ductus Arteriosus: Looking beyond the Prostaglandin Pathway

The ductus arteriosus (DA) is a physiologic vessel crucial for fetal circulation. As a major regulating factor, the prostaglandin pathway has long been the target for DA patency maintenance or closure. However, the adverse effect of prostaglandins and their inhibitors has been a major unsolved clinical problem. Furthermore, a significant portion of patients with patent DA fail to respond to cyclooxygenase inhibitors that target the prostaglandin pathway. These unresponsive medical patients ultimately require surgical intervention and highlight the importance of exploring pathways independent from this well-recognized prostaglandin pathway. The clinical limitations of prostaglandin-targeting therapeutics prompted us to investigate molecules beyond the prostaglandin pathway. Thus, this article introduces molecules independent from the prostaglandin pathway based on their correlating mechanisms contributing to vascular remodeling. These molecules may serve as potential targets for future DA patency clinical management.

Effects of nutrition therapy on growth, inflammation and metabolism in immature infants: a study protocol of a double-blind randomized controlled trial (ImNuT)

Background

Current nutritional management of infants born very preterm results in significant deficiency of the essential fatty acids (FAs) arachidonic acid (ARA) and docosahexaenoic acid (DHA). The impact of this deficit on brain maturation and inflammation mediated neonatal morbidities are unknown. The aim of this study is to determine whether early supply of ARA and DHA improves brain maturation and neonatal outcomes in infants born before 29 weeks of gestation.

Methods

Infants born at Oslo University Hospital are eligible to participate in this double-blind randomized controlled trial. Study participants are randomized to receive an enteral FA supplement of either 0.4 ml/kg MCT-oil™ (medium chain triglycerides) or 0.4 ml/kg Formulaid™ (100 mg/kg of ARA and 50 mg/kg of DHA). The FA supplement is given from the second day of life to 36 weeks’ postmenstrual age (PMA). The primary outcome is brain maturation assessed by Magnetic Resonance Imaging (MRI) at term equivalent age. Secondary outcomes include quality of growth, incidence of neonatal morbidities, cardiovascular health and neuro-development. Target sample size is 120 infants (60 per group), this will provide 80% power to detect a 0.04 difference in mean diffusivity (MD, mm²/sec) in major white matter tracts on MRI.

Discussion

Supplementation of ARA and DHA has the potential to improve brain maturation and reduce inflammation related diseases. This study is expected to provide valuable information for future nutritional guidelines for preterm infants.

Trial registration

Clinicaltrials.gov ID: NCT03555019. Registered 4 October 2018- Retrospectively registered.

Predictors of successful patent ductus arteriosus closure with acetaminophen in preterm infants

OBJECTIVE

Evaluate predictors of successful PDA closure following acetaminophen treatment.

STUDY DESIGN

Retrospective cohort study of ≤30 weeks GA infants born from 1 January 2013-30 September 2019, and treated with single course acetaminophen by symptomatic PDA treatment strategy. Multiple maternal and neonatal variables were identified as potential predictors. Univariate analysis and multivariable regression models were applied to evaluate the strongest predictors.

RESULTS

Sixty-six patients were included, 28 (42.4%) had successful PDA closure following acetaminophen. Success was associated with GA > 26 weeks (65% vs. 33%, AUC = 0.64), birthweight >750 g (53% vs. 32%, AUC = 0.61), PDA size ≤0.2 cm (63% vs. 32%, AUC = 0.64), and no prior indomethacin use (56% vs. 33%, AUC = 0.61). Multivariable model identified GA > 26 weeks (RR = 1.92, CI 1.20-3.09) and PDA size ≤0.2 cm (RR: 1.82, CI 1.11-2.98) as the strongest predictors.

CONCLUSION

Acetaminophen may be more successful in targeted PDA closure in >26 weeks GA infants with PDA size ≤0.2 cm.

Association of chorioamnionitis and patent ductus arteriosus in a national U.S. cohort

OBJECTIVE

To estimate the effect of clinical chorioamnionitis on the risk of patent ductus arteriosus (PDA).

STUDY DESIGN

A secondary analysis of all deliveries >23 gestational weeks from the U.S. Consortium on Safe Labor (CSL) study. The primary exposure was a clinical diagnosis of chorioamnionitis, and the outcome was a diagnosis of PDA. Generalized estimating equations with estimated error variance for women with multiple deliveries were utilized. Models adjusted for age, race, region, delivery year, body mass index, infant sex, multiple gestation, mode of delivery, and antenatal corticosteroid exposure.

RESULTS

Among 228,438 deliveries, a diagnosis of PDA was more frequent with chorioamnionitis exposure versus without (9.2% vs. 3.0%; OR: 3.25; 95% CI: 2.92-3.62). Chorioamnionitis was associated with higher adjusted odds of PDA (AOR: 2.18; 95% CI: 1.93-2.45). In sensitivity analyses, the association between chorioamnionitis and PDA held after adjustment for gestational age at delivery (AOR: 1.28; 95% CI: 1.13-1.44).

CONCLUSIONS

Chorioamnionitis was associated with increased odds of PDA. Robust exposure and outcome ascertainment with careful assessment of confounding is needed to further investigate this epidemiologic association.

Perinatal risk factors of symptomatic preterm patent ductus arteriosus and secondary ligation

BACKGROUND

There has been conflicting evidence for the association between antenatal factors and the development of symptomatic patent ductus arteriosus (PDA) or failure of pharmacologic treatment, especially for maternal pregnancy-induced hypertension (PIH) or chorioamnionitis. We assessed the perinatal risk factors of symptomatic PDA in preterm infants and those of secondary ligation in infants with pharmacologic treatment for symptomatic PDA using a national cohort.

METHODS

A total of 2961 infants with 22-29 weeks of gestation with symptomatic PDA or no PDA were included from the Korean Neonatal Network database. To identify significant perinatal risk factors associated with symptomatic PDA or secondary ligation, all perinatal factors were included in the univariate and multivariate generalized estimating equation analysis and final model was selected using backward elimination method based on Quasi-likelihood Information Criterion.

RESULTS

Lower gestational age (GA), female gender, maternal PIH and surfactant use were significant risk factors of symptomatic PDA. Antenatal corticosteroid use decreased the risk of symptomatic PDA. For secondary ligation, lower GA and cesarean section were significant risk factors. Adjusted odds ratio (aOR) of PIH as a risk factor of symptomatic PDA was 1.56 [95% confidence interval 1.17-2.08]. In the subgroup analysis according to the GA, lower GA, female gender, multiple pregnancy, maternal PIH and surfactant use increased the risk of symptomatic PDA, and histologic chorioamnionitis and antenatal corticosteroid use decreased the risk of symptomatic PDA only in GA 26-29 weeks group.

CONCLUSION

Lower GA increased the risk of symptomatic PDA and secondary ligation. Maternal PIH and surfactant use increased the risk of symptomatic PDA; however, antenatal corticosteroid use decreased it. Close observation of the clinical symptoms of PDA is needed in preterm infants with maternal PIH.

Plasma B-type natriuretic peptide cannot predict treatment response to ibuprofen in preterm infants with patent ductus arteriosus

Plasma B-type natriuretic peptide (BNP) is a useful marker for diagnosis of hemodynamically significant PDA (hsPDA) and serial BNP measurement is also valuable for monitoring treatment response. This retrospective study was performed to evaluate whether plasma BNP level can predict treatment response to ibuprofen in preterm infants born at <30 weeks of gestation with hsPDA. Plasma BNP was measured before (baseline) and 12 to 24 h after (post-treatment) completion of the first (IBU1) and second (IBU2) course of ibuprofen. We compared the BNP levels of responders (closed or insignificant PDA) with those of non-responders (hsPDA requiring further pharmacologic or surgical closure) to each course of ibuprofen. The treatment response rates for IBU1 (n = 92) and IBU2 (n = 19) were 74% and 26%, respectively. In IBU1, non-responders had lower gestational age and birth weight than responders (both, P = 0.004), while in IBU2, non-responders had lower birth weight (P = 0.014) and platelet counts (P = 0.005) than responders; however, baseline BNP levels did not differ significantly between responders and non-responders in either IBU1 (median 1,434 vs. 1,750 pg/mL) or IBU2 (415 vs. 596 pg/mL). Post-treatment BNP was a useful marker for monitoring treatment efficacy of IBU1 and IBU2 for hsPDA with a cut-off value of 331 pg/mL (P < 0.001) and 423 pg/mL(P < 0.010), respectively. We did not identify a cut-off baseline BNP level that could predict treatment response to ibuprofen in preterm infants with hsPDA.

Base excess and hematocrit predict response to indomethacin in very low birth weight infants with patent ductus arteriosus

Background

The treatment of patent ductus arteriosus (PDA) in very low birth weight (VLBW) infants remains a challenge. The ability to predict which infants will respond to indomethacin could spare some from the risks of unnecessary medications. Our objective was to determine if indicators of acid-base homeostasis could predict response to indomethacin treatment for ductal closure, and thus help guide treatment decisions.

Methods

We performed a retrospective analysis of medical records of VLBW (< 1500 g) neonates with hemodynamically significant PDA born at our institution between January 2009 and December 2012; all infants included in the study were treated with indomethacin for ductal closure within the first 2 weeks of life. We extracted data for a number of clinical variables including gestational age, birth weight, blood chemistries, surfactant use, hematocrit, and blood gas parameters. Our primary outcome measure was successful closure of PDA following the first round of indomethacin. Using variables that were significant on initial testing, we created multivariable regression models to determine the independent association of selected variables with indomethacin response.

Results

Of the 91 infants included in the study, 62 (68%) responded to the first course of indomethacin with successful ductal closure. Multivariable regression modeling revealed that both base excess and hematocrit were independently associated with indomethacin response; odds of PDA closure increased with increasing base excess (OR [odds ratio]: 1.81; 95% confidence interval [CI]: 1.36–2.60) and increasing hematocrit (OR: 1.21; 95% CI: 1.01–1.45). The optimal cutoff value for base excess was − 4.56, with a sensitivity of 96.8% (95% CI: 89–100) and specificity of 79.3% (95% CI: 60–92); optimal cutoff value for hematocrit was 40, with 69.4% sensitivity (95% CI: 56–80) and 65.5% specificity (95% CI: 46–82).

Conclusions

Base excess and hematocrit may be independent predictors of indomethacin response in VLBW infants with PDA. Low-cost and readily accessible, acid-base indicators such as base excess could help guide treatment decisions.

Electronic supplementary material

The online version of this article (10.1186/s13052-019-0706-y) contains supplementary material, which is available to authorized users.

CYP2C9*2 is associated with indomethacin treatment failure for patent ductus arteriosus

Aims: To identify clinical andgenetic factors associated with indomethacin treatment failure in preterm neonates with patent ductus arteriosus (PDA). Patients & Methods: This is a multicenter cohort study of 144 preterm infants (22-32 weeks gestational age) at three centers who received at least one treatment course of indomethacin for PDA. Indomethacin failure was defined as requiring subsequent surgical intervention. Results: In multivariate analysis, gestational age (AOR 0.76, 95% CI 0.60-0.96), surfactant use (AOR 9.77, 95% CI 1.15-83.26), and CYP2C9*2 (AOR 3.74; 95% CI 1.34-10.44) were each associated with indomethacin failure. Conclusion: Age, surfactant use, and CYP2C9*2 influence indomethacin treatment outcome in preterm infants with PDA. This combination of clinical and genetic factors may facilitate targeted indomethacin use for PDA.

The Associations between Antenatal Corticosteroids and In-Hospital Outcomes of Preterm Singleton Appropriate for Gestational Age Neonates according to the Presence of Maternal Histologic Chorioamnionitis

INTRODUCTION

This study aimed to assess the association between antenatal corticosteroid (ACS) and in-hospital outcomes of preterm singleton appropriate for gestational age (AGA) infants according to the presence of maternal histologic chorioamnionitis (HCA).

METHODS

A retrospective study was performed with singleton AGA neonates of 23+0 to 33+6 weeks' gestation born between 2007 and 2014. We compared the clinical outcomes according to the presence of HCA and ACS use. We also divided the ACS group into 2 groups: infants who received ACS 2-7 days before birth (optimal ACS) or not (suboptimal ACS). Multivariate logistic regression with Firth's penalized likelihood was performed.

RESULTS

In total, 254 neonates were eligible with 109 neonates with HCA (42.9%). In multivariate analysis adjusting for GA, sex, and cesarean section, ACS use was associated with reduced severe bronchopulmonary dysplasia (BPD) or death and hypotension within 7 postnatal days among the neonates with HCA. However, it was associated with increased patent ductus arteriosus (PDA) treatment. In the optimal ACS group, severe BPD or death (aOR 0.03, 95% CI 0.01-0.42), hypotension (aOR 0.02, 95% CI 0.01-0.26), and inhaled nitric oxide use (aOR 0.06, 95% CI 0.00-0.81) were lower, however, PDA treatment (aOR 8.14, 95% CI 1.20-55.24) and sepsis (aOR 6.85, 95% CI 1.02-46.07) were higher when compared with the no ACS group among HCA+ infants. Among HCA- infants, only PDA treatment was lower in the ACS group.

CONCLUSION

In neonates with HCA, ACS treatment was associated with reduced morbidities. However, increased sepsis was associated with optimal ACS use.

Turkish Neonatal Society guideline on the management of patent ductus arteriosus in preterm infants

Ductus arteriosus is a physiologic phenomenon in utero and it closes spontaneously in term babies. The closure is problematic in preterm infants due to the intrinsic properties of the preterm ductus arteriosus tissue. Although patent ductus arteriosus has been reported to be associated with many adverse outcomes in this population, treatment has not led to a decrease in outcomes such as bronchopulmonary dysplasia. Treatment modalities also have their own risks and restrictions. The aim of the "Turkish Neonatal Society guidelines for the management of patent ductus arteriosus in preterm babies" is to standardize the diagnosis and treatment of patent ductus arteriosus in preterm infants by combining the current scientific data and the resources of our country.

A promising, novel index in the diagnosis and follow-up of patent ductus arteriosus: Red cell distribution width-to-platelet ratio

BACKGROUND

The role of red cell distribution width-to-platelet ratio (RPR) has not previously been mentioned in reports on patent ductus arteriosus (PDA). Our objective was to evaluate whether RPR would have a role in the diagnosis and/or prediction of pharmacological closure of PDA.

METHODS

Preterm infants' gestational age ≤30 weeks and ≤1500 g who were given first ibuprofen treatment in the first week of life for hemodynamically significant PDA (hsPDA) were included in the study. The patients were matched for gestational age, birthweight, and sex. Patients were subdivided into two groups based on the response to medical treatment (open and closed PDA). Hemogram parameters were recorded before and after medical therapy. Groups were compared with regard to demographic and clinical characteristics and for three sequential hematological parameters. RPR was calculated. Patients with sepsis, anemia, perinatal asphyxia, and congenital/chromosomal anomaly were not included in the study.

RESULTS

A total of 112 infants had medically treated hsPDA. Of those, ductus closed in 70 neonates (closed PDA). A total of 96 infants constituted the control group. Mean gestational age and birthweight of the patients were 28.9 ± 2.4 weeks and 1207 ± 372 g. While RPR was significantly increased, PCT was lower in both hsPDA and open PDA groups (P < 0.05 and P < 0.05, respectively). In multivariate analysis, high RPR (OR 3.3, 95% CI 1.438-5.872, P < 0.05) and RDS (OR 2.9, 95% CI 1.903-4.811, P < 0.01) were detected as independent risk factors for hsPDA.

CONCLUSION

Red cell distribution width-to-platelet ratio and PCT may be promising supportive tools for the diagnosis and prediction of pharmacotherapy success.

Prediction of Therapeutic Response to Cyclooxygenase Inhibitors in Preterm Infants with Patent Ductus Arteriosus

Patent ductus arteriosus (PDA) is a morbid condition commonly seen in premature infants. Cyclooxygenase (COX) inhibitors, such as indomethacin and ibuprofen, are often used for the treatment of PDA in preterm infants, and they work by reducing the production of prostaglandin. However, as observed in clinical practice, not all PDAs in preterm infants can be closed using COX inhibitors. Some studies have demonstrated that gestational age, birth weight, B-type natriuretic peptide (BNP), and ductal diameter can predict the therapeutic responsiveness to COX inhibitors. This paper reviews the factors that can predict successful closure of the PDA in preterm infants using indomethacin or ibuprofen and presents new opinions and recent findings on this topic, including the predictive roles of intrauterine growth restriction, timing of the treatment, and the importance of platelet count and arterial pH. We also discuss the prospects for future studies to improve the individualized therapy of PDA in premature neonates.

IL-17 in neonatal health and disease

Over the last few years, scientific interest in the cytokine IL-17A has intensified as its role in human health and disease has been elucidated. Discovered almost a quarter century ago, IL-17A is known to have poor biologic activity when acting alone, but attains robust actions when working synergistically with potent mediators of proinflammatory immune responses, such as IL-6 and IL-8. IL-17A is produced by specialized innate immune cells that protect host barriers from the outside world. Like sentries, these innate immune cells can "sound the alarm" through increased production of IL-17A, causing activation and recruitment of primed neutrophils and monocytes when pathogens escape initial host defenses. In this way, IL-17A promulgates mechanisms responsible for pathogen death and clearance. However, when IL-17A pathways are triggered during fetal development, due to chorioamnionitis or in utero inflammatory conditions, IL-17A can instigate and/or exacerbate fetal inflammatory responses that increase neonatal morbidities and mortality associated with common neonatal conditions such as sepsis, bronchopulmonary dysplasia (BPD), patent ductus arteriosus (PDA), and necrotizing enterocolitis (NEC). This review details the ontogeny of IL-17A in the fetus and newborn, discusses how derangements in its production can lead to pathology, and describes known and evolving therapies that may attenuate IL-17A-mediated human conditions.

Efficacy of pharmacologic closure of patent ductus arteriosus in small-for-gestational-age extremely preterm infants

BACKGROUND

Optimal management of the patent ductus arteriosus (PDA) in preterm infants remains controversial. Therefore, studies identifying infants who are most likely to benefit from PDA treatment are needed.

AIM

We sought to examine if significant intrauterine growth restriction, defined by birth weight z-score, reduces the efficacy of PDA closure with indomethacin or ibuprofen and thereby increases the need for surgical closure of PDA after pharmacologic treatment.

STUDY DESIGN, SUBJECTS, AND OUTCOME MEASURES

We studied infants 23-28weeks' gestation born 2006-2013 at NICHD Neonatal Research Network centers. We examined the responses to PDA treatment with indomethacin and/or ibuprofen and whether the PDA was subsequently closed surgically. Logistic regression generated adjusted odds ratios (ORs) for the associations between the z-score groups (<-2, -2 to -0.5, and >-0.5) and PDA surgery following pharmacologic treatment.

RESULTS

5606 infants were diagnosed with PDA; 3587 (64.0%) received indomethacin or ibuprofen or both, and 909 (25.3%) underwent PDA surgery. Mothers of infants with PDA non-closure were less likely to have hypertension (19% vs. 28%). Infants with non-closure were more likely to be female (53% vs. 49%), have lower gestational age and birth weight and to develop sepsis (42% vs. 31%). Compared to infants with z-score>-0.5, PDA surgery was increased among infants with z-score -2 to -0.5 (OR=1.23; 95% CI 1.02-1.47) but not among infants with z-score<-2.

CONCLUSION

Infants with birth weight z-score -2 to -0.5 are more likely than normally grown infants to require PDA surgery following pharmacologic treatment.

Paracetamol in Patent Ductus Arteriosus Treatment: Efficacious and Safe?

In preterm infants, failure or delay in spontaneous closure of Ductus Arteriosus (DA), resulting in the condition of Patent Ductus Arteriosus (PDA), represents a significant issue. A prolonged situation of PDA can be associated with several short- and long-term complications. Despite years of researches and clinical experience on PDA management, unresolved questions about the treatment and heterogeneity of clinical practices in different centers still remain, in particular regarding timing and modality of intervention. Nowadays, the most reasonable strategy seems to be reserving the treatment only to hemodynamically significant PDA. The first-line therapy is medical, and ibuprofen, related to several side effects especially in terms of nephrotoxicity, is the drug of choice. Administration of oral or intravenous paracetamol (acetaminophen) recently gained attention, appearing effective as traditional nonsteroidal anti-inflammatory drugs (NSAIDs) in PDA closure, with lower toxicity. The results of the studies analyzed in this review mostly support paracetamol efficacy in ductal closure, with inconstant low and transient elevation of liver enzymes as reported side effect. However, more studies are needed to confirm if this therapy shows a real safety profile and to evaluate its long-term outcomes, before considering paracetamol as first-choice drug in PDA treatment.

Persistent Ductus Arteriosus in Critically Ill Preterm Infants

Introduction

Persistent ductus arteriosus (PDA) is found with increased incidence in preterm infants, significantly affecting neonatal morbidity and mortality rates.

Aim

To evaluate the association between the presence of PDA and the severity of clinical condition at birth in critically ill preterm infants, with gestational ages (GA) ≤ 32 weeks and severe respiratory distress.

Methods

All preterm infants with GA ≤ 32 weeks admitted to the neonatal intensive care unit (NICU) of the Clinical County Emergency Hospital, Sibiu between 1 January 2010 and 31 December 2015 were included in the study. These were categorized as Group 1 [Preterm infants with PDA; n=154] and Group 2 [Preterm infants without PDA; n=186]. Epidemiological and clinical data were collected in the National Registry for Respiratory Distress Syndrome for all children, and data related to prenatal period, clinical characteristics at birth i.e GA, weight, gender, Apgar scores, and clinical features such as resuscitation at birth, surfactant administration, need and duration of respiratory support, neonatal sepsis, complications associated with prematurity, and death, were analyzed.

Results

Group 1 infants had significantly lower GA and birth weights, were more often out born (p=0.049, HR 1.69), and had significantly lower Apgar scores at 1 and 10 minutes (p=0.022, p=0.000). They presented a significantly higher need for surfactant administration (42.9% vs 24.7%, p<0.0001) and respiratory support (96.8% vs 90.3%, HR 3.19, p=0.019 for need of CPAP and 22.1% vs 10.8%, HR 2.35, p=0.004 for mechanical ventilation). Duration of respiratory support was also significantly higher in the Group 1 (7.6%±7.5 vs. 5.1±3.8 days, p<0.0001 for CPAP and 20.1±22.5 vs. 12.0±15.7 days, p<0.0001 for mechanical ventilation).

Conclusion

In very preterm infants, PDA may be associated with a critical clinical condition leading to serious complications. The presence of PDA after the seventh day of life was associated with an increased need for respiratory support, both CPAP and mechanical ventilation, increased severity of the respiratory distress syndrome, requiring a longer duration of respiratory support, and increased the hospitalization length. In very preterm infants, PDA presence was also associated with a higher rate of severe complications and death, indicating the need for a careful and proper management of these critical cases in neonatal intensive care units.

[Risk factors for patent ductus arteriosus in early preterm infants: a case-control study]

OBJECTIVE

To investigate the risk factors for the occurrence of patent ductus arteriosus (PDA) and to provide a clinical basis for reducing the occurrence of PDA in early preterm infants.

METHODS

A total of 136 early preterm infants (gestational age≤32 weeks) who were hospitalized between January 2013 and December 2014 and diagnosed with hemodynamicalhy significant PDA (hs-PDA) were enrolled as the case group. Based on the matched case-control principle, 136 early preterm infants without hs-PDA were selected among those who were hospitalized within the same period at a ratio of 1:1 and enrolled as the control group. The two groups were matched for sex and gestational age. The basic information of neonates and maternal conditions during the pregnancy and perinatal periods were collected. Logistic regression analysis was performed to identify the risk factors for the development of PDA.

RESULTS

Univariate analysis showed that neonatal infectious diseases, neonatal respiratory distress syndrome, decreased platelet count within 24 hours after birth, and low birth weight were associated with the development of hs-PDA (P<0.05). Multivariate conditional logistic regression analysis revealed that neonatal infectious diseases (OR=2.368) and decreased platelet count within 24 hours after birth (OR=0.996) were independent risk factors for hs-PDA.

CONCLUSIONS

Neonatal infectious diseases and decreased platelet count within 24 hours after birth increase the risk of hs-PDA in early preterm infants.

Chorioamnionitis and Patent Ductus Arteriosus: A Systematic Review and Meta-Analysis

Background

Chorioamnionitis has recently been reported as a risk factor for various neonatal diseases, including cerebral palsy, bronchopulmonary dysplasia, and necrotizing enterocolitis, but its effect on patent ductus arteriosus (PDA) is unclear. We performed a systematic review and meta-analysis to evaluate the effect of chorioamnionitis on PDA.

Methods

We searched PubMed, EMBASE, Cochrane Library, and KoreaMed databases using the terms: “intrauterine infection” or “maternal infection” or “antenatal infection” or “chorioamnionitis” or “placenta inflammation” or “placenta pathology” or “neonatal outcome” or “neonatal morbidity” or “PDA or patent ductus arteriosus” or “ductus arteriosus,” and “prematurity” or “very low birth weight infant.” Studies were included if they were randomized controlled trials, case–control studies, or cohort studies that included information relating to chorioamnionitis and PDA.

Results

Among 1,571 studies, a total of 23 studies (17,708 cases) were included in the meta-analysis to analyze the relationship between chorioamnionitis and PDA, except one study that only included PDA requiring surgical ligation. The association between chorioamnionitis and PDA was statistically significant (odds ratio [OR] 1.43; 95% confidence interval [CI] 1.19, 1.72; P < 0.0001). In subgroup analysis, clinical chorioamnionitis was not associated with PDA (OR 1.28; 95% CI 1.00, 1.64, 1.790; P = 0.05), whereas histologic chorioamnionitis (OR 1.54; 95% CI 1.10, 2.15; P = 0.01) and chorioamnionitis diagnosed from both clinical and histologic findings (OR 1.75; 95% CI 1.07, 2.86; P = 0.03) showed significant associations with PDA. Chorioamnionitis did not increase the risk of PDA requiring surgical ligation (OR 1.23; 95% CI 0.69, 2.17; P = 0.48), and antenatal steroid use reduced the risk of PDA (OR 0.62; 95% CI 0.42, 0.90; P = 0.01) after chorioamnionitis.

Conclusions

The results from this meta-analysis support an association between maternal chorioamnionitis and PDA in offspring.

Predictors of successful closure of patent ductus arteriosus with indomethacin

OBJECTIVE

To determine whether platelet counts can predict the likelihood of successful closure of patent ductus arteriosus (PDA) with indomethacin.

STUDY DESIGN

This was a retrospective cohort study of infants <32 weeks' gestational age (GA) and birth weight <1500 g with PDA. Clinical characteristics between infants who achieved ductal closure with indomethacin and those who failed were compared. Multivariable logistic regression was used to identify predictors of successful ductal closure.

RESULTS

In infants with hemodynamically significant PDA, older GA (odds ratio=1.54; 95% confidence interval: 1.12 to 2.13), male gender (odds ratio=3.02; 95% confidence interval: 1.08 to 8.49) and higher platelet count (odds ratio=1.5; 95% confidence interval: 1.04 to 2.17) prior to indomethacin treatment were associated with successful ductal closure with indomethacin.

CONCLUSION

Older GA, male gender and higher platelet count at time of treatment of hemodynamically significant PDA are predictors of successful ductal closure with indomethacin.

Cord blood and consecutive chitotriosidase activity: Relationship to prematurity and early prognosis

BACKGROUND

The aim of this study was to investigate the relationship between plasma chitotriosidase activity, an inflammatory protein secreted mainly from macrophages, and neonatal morbidity and mortality in premature infants.

METHODS

Cord blood chitotriosidase activity was studied in healthy control infants (53 term, group 1; 26 late preterm [33-37 gestational weeks], group 2) and 35 preterm infants (≤ 32 weeks; group 3). In group 3, consecutive samples at 3 h, 24 h, 72 h, 7 days, 14 days, and 36 weeks after conception were also analyzed. Group 3 was also evaluated for mortality, respiratory treatment and bronchopulmonary dysplasia (BPD), patent ductus arteriosus (PDA), intraventricular hemorrhage (IVH) and retinopathy of prematurity (ROP) and necrotizing enterocolitis (NEC).

RESULTS

Cord blood chitotriosidase activity was positively correlated with gestational age and birthweight. SNAPPE-II score was correlated with chitotriosidase activity at 24 h. Consecutive chitotriosidase activity for group 3 was non-significantly higher in infants who died in the early neonatal period. Higher chitotriosidase activity was observed in mechanically ventilated infants than infants treated with non-invasive assisted ventilation. BPD, PDA, IVH and ROP, but not NEC, were related to higher chitotriosidase activity, being significant at some of the time points.

CONCLUSION

Neonatal stress such as invasive ventilation may create a risk for the development of BPD, PDA, IVH, and ROP by increasing macrophage activation in preterm infants as reflected in the higher chitotriosidase activity. High chitotriosidase activity may also be associated with disease severity and mortality.

Aminoglycoside-mediated relaxation of the ductus arteriosus in sepsis-associated PDA

Sepsis is strongly associated with patency of the ductus arteriosus (PDA) in critically ill newborns. Inflammation and the aminoglycoside antibiotics used to treat neonatal sepsis cause smooth muscle relaxation, but their contribution to PDA is unknown. We examined whether: 1) lipopolysaccharide (LPS) or inflammatory cytokines cause relaxation of the ex vivo mouse DA; 2) the aminoglycosides gentamicin, tobramycin, or amikacin causes DA relaxation; and 3) newborn infants treated with aminoglycosides have an increased risk of symptomatic PDA (sPDA). Changes in fetal mouse DA tone were measured by pressure myography in response to LPS, TNF-α, IFN-γ, macrophage-inflammatory protein 2, IL-15, IL-13, CXC chemokine ligand 12, or three aminoglycosides. A clinical database of inborn patients of all gestations was analyzed for association between sPDA and aminoglycoside treatment. Contrary to expectation, neither LPS nor any of the inflammatory mediators caused DA relaxation. However, each of the aminoglycosides caused concentration-dependent vasodilation in term and preterm mouse DAs. Pretreatment with indomethacin and N-(G)-nitro-L-arginine methyl ester did not prevent gentamicin-induced DA relaxation. Gentamicin-exposed DAs developed less oxygen-induced constriction than unexposed DAs. Among 488,349 infants who met the study criteria, 40,472 (8.3%) had sPDA. Confounder-adjusted odds of sPDA were higher in gentamicin-exposed infants, <25 wk and >32 wk. Together, these findings suggest that factors other than inflammation contribute to PDA. Aminoglycoside-induced vasorelaxation and inhibition of oxygen-induced DA constriction support the paradox that antibiotic treatment of sepsis may contribute to DA relaxation. This association was also found in newborn infants, suggesting that antibiotic selection may be an important consideration in efforts to reduce sepsis-associated PDA.

Hemodynamic changes in preterm neonates with septic shock: a prospective observational study*

OBJECTIVE

We evaluated hemodynamic changes in preterm neonates with septic shock using functional echocardiography and studied the effects of vasoactive drugs on hemodynamic variables.

DESIGN

Prospective observational study.

SETTING

Level III neonatal ICU.

SUBJECTS AND PATIENTS

We enrolled 52 preterm neonates with septic shock (shock group) and an equal number of gestation and postnatal age-matched healthy neonates (control group).

INTERVENTIONS

We measured functional hemodynamic variables (left and right ventricular output, ejection fraction, isovolumetric relaxation time, and early passive to late active peak velocity ratio) by echocardiography in the shock group during initial fluid resuscitation, before initiation of vasoactive drugs, and again 30-40 minutes after initiation of vasoactive drug infusion. Control group underwent a single assessment after enrollment. We compared various hemodynamic variables between shock group and control group using paired t test or Wilcoxon signed-rank test.

MEASUREMENTS AND MAIN RESULTS

The baseline left ventricular output was significantly higher in neonates with septic shock as compared with controls (median [interquartile range], 305 mL/kg/min [204, 393] vs 233 mL/kg/min [204, 302]; p < 0.001), but ejection fraction was similar between the two groups (55% ± 12% vs 55% ± 5%, p = 0.54). Other hemodynamic variables were comparable between the two groups. After vasoactive drug infusion, there was a significant increase in heart rate (152 ± 18 to 161 ± 18 beats/min, p ≤ 0.001) and right ventricular output (median [interquartile range], 376 [286, 468] to 407 [323, 538] mL/kg/min; p = 0.018) compared with the baseline, but left ventricular output and ejection fraction did not change significantly.

CONCLUSIONS

We found an elevated left ventricular output but normal ejection fraction in preterm neonates with septic shock. This suggests that septic shock in preterm neonates is predominantly due to vasoregulatory failure. Vasoactive drugs significantly increased right ventricular output, which was predominantly due to increase in heart rate.

Cord blood levels of osteopontin as a phenotype marker of gestational age and neonatal morbidities

OBJECTIVES

Osteopontin (OPN) is a proinflammatory cytokine associated with metabolic syndrome. Extreme birth weight categories including small for gestational age (SGA), and large for gestational age (LGA) are risk factors for metabolic syndrome. However normal levels of plasma OPN in neonates and the relationship of OPN to fetal growth remain unknown. We evaluated the association of umbilical cord blood OPN with gestational age, birth weight, and neonatal outcomes.

METHODS

A cross-sectional study of 261 newborns of all gestational ages beginning at week 26, and 26 adults for comparison was performed. Umbilical cord blood from newborns and analyzed plasma for OPN by ELISA was collected.

RESULTS

Plasma OPN was significantly higher in neonates (414.65 ± 136.72 ng/mL) compared to adults (33.37 ± 14.66 ng/mL, P < 0.001). There was an inverse correlation between OPN and gestational age (r = -0.48, P < 0.0001). LGA infants had lower OPN than appropriate for gestational age (AGA) infants, but LGA was not an independent predictor of OPN in multivariate analysis. Among preterm infants, patent ductus arteriosus (PDA) was independently associated with higher OPN (OR = 2.49, P = 0.02).

CONCLUSION

Our results raise the possibility that OPN has a physiologic role in fetal growth and development, and may be a useful biomarker for PDA.

Evidence-based use of indomethacin and ibuprofen in the neonatal intensive care unit

Indomethacin and ibuprofen are potent inhibitors of prostaglandin synthesis. Neonates have been exposed to these compounds for more than 3 decades. Indomethacin is commonly used to prevent intraventricular hemorrhage (IVH), and both drugs are prescribed for the treatment or prevention of patent ductus arteriosus (PDA). This review examines the basis for indomethacin and ibuprofen use in the neonatal intensive care population. Despite the call for restrained use of each drug, the most immature infants are likely to need pharmacologic approaches to reduce high-grade IVH, avoid the need for PDA ligation, and preserve the opportunity for an optimal outcome.

Outcomes of small for gestational age micropremies depending on how young or how small they are

Purpose

The outcomes of small for gestational age (SGA) infants especially in extremely low birth weight infants (ELBWIs) are controversial. This study evaluated the mortality and morbidity of ELBWIs, focusing on whether or not they were also SGA.

Methods

The medical records of 415 ELBWIs (birth weight <1,000 g), who were inborn and admitted to the Samsung Medical Center neonatal intensive care unit from January 2000 to December 2008, were reviewed retrospectively. Mortality and morbidities were compared by body size groups: very SGA (VSGA), birth weight ≤3rd percentile; SGA, 3rd to 10th percentile; and appropriate for gestational age (AGA) infants, >10th percentile for gestational age. For gestational subgroup analysis, groups were divided into infants with gestational age ≤24⁺⁶ weeks (subgroup I), 25⁺⁰ to 26⁺⁶ weeks (subgroup II), and ≥27⁺⁰ weeks (subgroup III).

Results

Gestational age was 29⁺²±2⁺⁶ weeks in the VSGA infants (n=49), 27⁺⁵±2⁺² weeks in the SGA infants (n=45), and 25⁺⁴±1⁺⁴ weeks in AGA infants (n=321). Birth weight was 692±186.6 g, 768±132.9 g, and 780±142.5 g in the VSGA, SGA, and AGA groups, respectively. Cesarean section rate and maternal pregnancy-induced hypertension were more common in the VSGA and SGA than in AGA pregnancies. However, chorioamnionitis was more common in the AGA group. The mortalities of the lowest gestational group (subgroup I), and also of the lower gestational group (subgroup I+II) were significantly higher in the VSGA group than the SGA or AGA groups (P=0.020 and P=0.012, respectively). VSGA and SGA infants showed lower incidence in respiratory distress syndrome, ductal ligation, bronchopulmonary dysplasia, intraventricular hemorrhage than AGA group did. However, by multiple logistic regression analysis of each gestational subgroup, the differences were not significant.

Conclusion

Of ELBWIs, extremely SGA in the lower gestational subgroups, had an impact on mortality, which may provide information useful for prenatal counseling.