Association of Antenatal Corticosteroids With Mortality, Morbidity, and Neurodevelopmental Outcomes in Extremely Preterm Multiple Gestation Infants

Association of different doses of antenatal corticosteroids exposure with early major outcomes and early weight loss percentage in extremely preterm infants or extremely low birthweight infants: a multicentre cohort study

OBJECTIVES

To determine the dose-dependent associations between antenatal corticosteroids (ANS) exposure and the rates of major morbidities, and the early weight loss percentage (EWLP) in hospital among extremely preterm infants (EPI) or extremely low birthweight infants (ELBWI).

METHODS

A multicentre, retrospective cohort study of EPI or ELBWI born between 2017 and 2018 was conducted. Infants were classified into no ANS, partial ANS and complete ANS exposure group; three subgroups were generated by gestational age and birth weight. Multiple logistic regression and multiple linear regression were performed.

RESULTS

There were 725 infants included from 32 centres. Among no ANS, partial ANS and complete ANS exposure, there were significant differences in the proportions of bronchopulmonary dysplasia (BPD) (24.5%, 25.4% and 16.1%), necrotising enterocolitis (NEC) (6.7%, 2.0% and 2.0%) and death (29.6%, 18.5% and 13.5%), and insignificant differences in the proportions of intraventricular haemorrhage (IVH) (12.5%, 13.2% and 12.2%), and extrauterine growth restriction (EUGR) (50.0%, 56.6% and 59.5%). In the logistic regression, compared with no ANS exposure, complete ANS reduced the risk of BPD (OR 0.58, 95% CI 0.37 to 0.91), NEC (OR 0.21, 95% CI 0.08 to 0.57) and death (OR 0.36, 95% CI 0.23 to 0.56), and partial ANS reduced the risk of NEC (OR 0.23, 95% CI 0.07 to 0.72) and death (OR 0.54, 95% CI 0.34 to 0.87). Compared with partial ANS exposure, complete ANS decreased the risk of BPD (OR 0.58, 95% CI 0.37 to 0.91). There were insignificant associations between ANS exposure and IVH, EUGR. In the multiple linear regression, partial and complete ANS exposure increased EWLP only in the ≥28 weeks (w) and <1000 g subgroup (p<0.05).

CONCLUSIONS

Different doses of ANS (dexamethasone) exposure were protectively associated with BPD, NEC, death in hospital, but not EUGR at discharge among EPI or ELBWI. Beneficial dose-dependent associations between ANS (dexamethasone) exposure and BPD existed. ANS exposure increased EWLP only in the ≥28 w and<1000 g subgroup. ANS administration, especially complete ANS, is encouraged before preterm birth.

TRIAL REGISTRATION NUMBER

NCT06082414.

Predicting early mortality and severe intraventricular hemorrhage in very-low birth weight preterm infants: a nationwide, multicenter study using machine learning

Our aim was to develop a machine learning-based predictor for early mortality and severe intraventricular hemorrhage (IVH) in very-low birth weight (VLBW) preterm infants in Taiwan. We collected retrospective data from VLBW infants, dividing them into two cohorts: one for model development and internal validation (Cohort 1, 2016-2021), and another for external validation (Cohort 2, 2022). Primary outcomes included early mortality, severe IVH, and early poor outcomes (a combination of both). Data preprocessing involved 23 variables, with the top four predictors identified as gestational age, birth body weight, 5-min Apgar score, and endotracheal tube ventilation. Six machine learning algorithms were employed. Among 7471 infants analyzed, the selected predictors consistently performed well across all outcomes. Logistic regression and neural network models showed the highest predictive performance (AUC 0.81-0.90 in both internal and external validation) and were well-calibrated, confirmed by calibration plots and the lowest two mean Brier scores (0.0685 and 0.0691). We developed a robust machine learning-based outcome predictor using only four accessible variables, offering valuable prognostic information for parents and aiding healthcare providers in decision-making.

Antenatal Corticosteroids at 21-23 Weeks of Gestation

Neonates born at the cusp of viability are at particularly high risk of severe morbidity and mortality. With advances in medicine and technology, the ability to resuscitate smaller, more premature neonates has become possible, and survival as early as 21 weeks of gestation has been reported. Although administration of antenatal corticosteroids has been shown to reduce the risk of morbidity and mortality at later gestational ages, neonates born before 24 weeks of gestation have not been included in randomized clinical trials. Changing clinical practices surrounding neonatal resuscitation with intervention offered after birth at earlier gestational ages has prompted re-evaluation of the use of antenatal corticosteroids at these very early gestational ages. Recent observational data demonstrate that antenatal corticosteroids administered before deliveries at or after 22 weeks of gestation are associated with lower risks of neonatal mortality, although survival with severe morbidity remains high. Future research is needed to determine the efficacy of antenatal corticosteroids for deliveries before 22 weeks of gestation and should evaluate the timing of corticosteroid administration. Furthermore, efforts should be made to include diverse populations and clinically meaningful long-term outcomes. At this time, the decision surrounding antenatal corticosteroids for threatened periviable deliveries should incorporate multidisciplinary counseling with the goal of achieving concordant prenatal and postnatal management aligned with the patient's desires.

Development and validation of a model to predict mortality risk among extremely preterm infants during the early postnatal period: a multicentre prospective cohort study

BACKGROUND

Recently, with the rapid development of the perinatal medical system and related life-saving techniques, both the short-term and long-term prognoses of extremely preterm infants (EPIs) have improved significantly. In rapidly industrialising countries like China, the survival rates of EPIs have notably increased due to the swift socioeconomic development. However, there is still a reasonably lower positive response towards the treatment of EPIs than we expected, and the current situation of withdrawing care is an urgent task for perinatal medical practitioners.

OBJECTIVE

To develop and validate a model that is practicable for EPIs as soon as possible after birth by regression analysis, to assess the risk of mortality and chance of survival.

METHODS

This multicentre prospective cohort study used datasets from the Sino-Northern Neonatal Network, including 46 neonatal intensive care units (NICUs). Risk factors including maternal and neonatal variables were collected within 1 hour post-childbirth. The training set consisted of data from 41 NICUs located within the Shandong Province of China, while the validation set included data from 5 NICUs outside Shandong Province. A total of 1363 neonates were included in the study.

RESULTS

Gestational age, birth weight, pH and lactic acid in blood gas analysis within the first hour of birth, moderate-to-severe hypothermia on admission and adequate antenatal corticosteroids were influencing factors for EPIs' mortality with important predictive ability. The area under the curve values for internal validation of our prediction model and Clinical Risk Index for Babies-II scores were 0.81 and 0.76, and for external validation, 0.80 and 0.51, respectively. Moreover, the Hosmer-Lemeshow test showed that our model has a constant degree of calibration.

CONCLUSIONS

There was good predictive accuracy for mortality of EPIs based on influencing factors prenatally and within 1 hour after delivery. Predicting the risk of mortality of EPIs as soon as possible after birth can effectively guide parents to be proactive in treating more EPIs with life-saving value.

TRIAL REGISTRATION NUMBER

ChiCTR1900025234.

Management of preterm labor: Clinical practice guideline and recommendation by the WAPM-World Association of Perinatal Medicine and the PMF-Perinatal Medicine Foundation

This practice guideline follows the mission of the World Association of Perinatal Medicine in collaboration with the Perinatal Medicine Foundation, bringing together groups and individuals throughout the world, with the goal of improving the management of preterm labor. In fact, this document provides further guidance for healthcare practitioners on the appropriate use of examinations with the aim to improve the accuracy in diagnosing preterm labor and allow timely and appropriate administration of tocolytics, antenatal corticosteroids and magnesium sulphate and avoid unnecessary or excessive interventions. Therefore, it is not intended to establish a legal standard of care. This document is based on consensus among perinatal experts throughout the world in the light of scientific literature and serves as a guideline for use in clinical practice.

Intracranial hemorrhages in infants of diabetic mothers: A national cohort study

OBJECTIVE

To assess the association of maternal diabetes mellitus (DM) with intraventricular hemorrhage (IVH) and other intracranial hemorrhages (ICH) in newborns.

STUDY DESIGN

We analyzed the National Inpatient Sample dataset and compared prevalence of IVH and other subtypes of ICH in infants of diabetic mothers (IDMs) vs. those born to mothers without DM. Regression models were used to control for demographic and clinical confounding variables.

RESULT

A total of 11,318,691 infants were included. Compared to controls, IDMs had increased prevalence of IVH (aOR = 1.18, CI: 1.12-1.23, p < 0.001) and other ICH (aOR = 1.18, CI: 1.07-1.31, p = 0.001). Severe IVH (grades 3 & 4) was encountered less frequently in IDMs (aOR = 0.75, CI: 0.66-0.85, p < 0.001) than controls. Gestational DM was not associated with increased IVH after controlling for the demographic, clinical and perinatal confounders in the logistic regression model (aOR = 1.04, CI: 0.98-1.11, p = 0.22).

CONCLUSION

Chronic maternal DM is associated with increased neonatal IVH and other ICH but not severe IVH. This association needs to be confirmed in further studies.

Effects of antenatal corticosteroids on neonatal outcomes in twin and singleton pregnancies: a Korean national cohort study

OBJECTIVE

To investigate whether effects of antenatal corticosteroids on neonatal outcomes in preterm infants with very low birth weight were different by plurality.

DESIGN

Nationwide prospective cohort study.

PATIENTS

Twins and singletons with very low birth weight (<1500 g) who were born between 23+0 and 33+6 weeks of gestation and registered in the Korean Neonatal Network from January 2014 to December 2019.

MAIN OUTCOME MEASURES

Morbidity and mortality before discharge from neonatal intensive care unit.

RESULTS

Among a total of 9531 preterm infants with very low birth weight, there were 2364 (24.8%) twins and 7167 (75.2%) singletons. While 83.9% of singletons were exposed to at least one dose of antenatal corticosteroids, so were 87.9% of twins.Interaction analysis demonstrated that there was no significant difference in the effect of antenatal corticosteroids on morbidities or mortality between twins and singletons in either gestational age group (23-28 weeks or 29-33 weeks).Antenatal corticosteroids significantly decreased the risk of surfactant use (adjusted relative risk (aRR): 0.972 (95% CI: 0.961 to 0.984)), high-grade intraventricular haemorrhage (aRR: 0.621 (95% CI: 0.487 to 0.794)), periventricular leucomalacia (aRR: 0.728 (95% CI: 0.556 to 0.954)) and mortality (aRR: 0.758 (95% CI: 0.679 to 0.846)) in the gestational age group of 23-28 weeks. In the gestational age group of 29-33 weeks, antenatal corticosteroids significantly decreased the risk of surfactant use (aRR: 0.914 (95% CI: 0.862 to 0.970)) and mortality (aRR: 0.409 (95% CI: 0.269 to 0.624)) but increased the risk of sepsis (aRR: 1.416 (95% CI: 1.018 to 1.969)).

CONCLUSION

This study demonstrates that effect of antenatal corticosteroids on neonatal outcomes of preterm infants with very low birth weight does not differ significantly by plurality (twin or singleton pregnancy).

Care practices and short-term clinical outcomes of very low birth weight infants in Yangtze River Delta in China

BACKGROUND

Intensive care is of great significance for very low birth weight infants (VLBWI). The Yangtze River Delta is the most ecomonically developed area in China. However, there are few data on the care practices and survival of VLBWI in this region.

OBJECTIVES

To investigate the prevalence, care practices and motality of VLBWI in Yangtze River Delta in China.

METHODS

A multi-center retrospective investigation study was conducted at five tertiary hospitals within the Yangtze River Delta in China from January to December 2017. Clinical data included the general characteristics of the infants and the mothers, clinical prognosis, care practices in NICUs was collected by trained research members.

RESULTS

During the study period, 1059 VLBWIs were included. Infants with birth weight < 750 g, 750-1000 g, 1000-1250 g and 1250-1500 g accounted for 2.3, 14.9, 34.8 and 47.8%, respectively. Premature rupture of membranes (17.8%) was the main cause of premature delivery. The catheterization rates of umbilical vein catheterization (UVC) and peripherally inserted central catheter (PICC) were 25.0 and 64.4%, respectively. The duration of parenteral nutrition was 27.0 ± 19.5 d, the meantime of feeding tube indwelling was 36.2 ± 24.2 d. The corrected gestational age of the infants who reached full oral feeding was 35.8 ± 2.7 weeks. The breast feeding rate in the investigated infants was 61.9%. The mortality rate of preterm infants was 3.4%. The incidence of main complications BPD, PDA, ROP, NEC and sepsis were 24.9, 29.9, 21.7, 9.4 and 13.3% respectively.

CONCLUSIONS

Maternal and infant care practices need to be improved in the very preterm births. This study provides a baseline for the improvement in the further study.

Perinatal management: Lessons learned from the neonatal research network

Recent contributions of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network (NRN) regarding obstetrical perinatal interventions and neonatal delivery room practices include the following: the impact of multiple antepartum factors including maternal diabetes, hypertension, obesity and mode of delivery on outcomes of extremely preterm newborns, effects of delayed delivery interval for extremely preterm multiples, effects of antenatal steroids on preterm newborn outcomes and the impact of antenatal magnesium sulfate therapy on neurodevelopmental outcomes for extremely preterm infants. NRN studies also contribute important evidence for neonatal delivery room resuscitation guidelines including umbilical cord management and maintenance of euthermia immediately after birth. The updated NRN outcome calculator helps better counsel families regarding possible outcomes for the most immature newborns if resuscitation is attempted at birth. Thus, the NRN provides substantial information regarding effects of perinatal management on newborn infants.

The variation of antenatal corticosteroids administration for the singleton preterm birth in China, 2017 to 2018

Background

The administration of antenatal corticosteroids (ACS) to women who are at risk of preterm birth has been proven to reduce not only the mortality, but also the major morbidities of the preterm infants. The rate of ACS and the risk factors associated with ACS use in Chinese population is unclear. This study aimed to investigate the rate of ACS use and the associated perinatal factors in the tertiary maternal centers of China.

Methods

Data for this retrospective observational study came from a clinical database of preterm infants established by REIN-EPIQ trial. All infants born at < 34 weeks of gestation and admitted to 18 tertiary maternal centers in China from 2017 to 2018 were enrolled. Any dose of dexamethasone was given prior to preterm delivery was recorded and the associated perinatal factors were analyzed.

Results

The rate of ACS exposure in this population was 71.2% (range 20.2 – 92%) and the ACS use in these 18 maternal centers varied from 20.2 to 92.0% in this period. ACS exposure was higher among women with preeclampsia, caesarean section delivery, antibiotic treatment and who delivered infants with lower gestational age and small for gestational age. ACS use was highest in the 28–31 weeks gestational age group, and lowest in the under 26 weeks of gestational age group (x² = 65.478, P < 0.001). ACS exposure was associated with lower odds of bronchopulmonary dysplasia or death (OR, 0.778; 95% CI 0.661 to 0.916) and invasive respiration requirement (OR, 0.668; 95% CI 0.585 to 0.762) in this population.

Conclusion

The ACS exposure was variable among maternity hospitals and quality improvement of ACS administration is warranted.

Serial Short-Term Outcomes of Very-Low-Birth-Weight Infants in the Korean Neonatal Network From 2013 to 2020

BACKGROUND

We aimed to determine the current survival rate and short-term outcomes of very-low-birth-weight infants (VLBWIs) in Korea, as well as whether the survival rate and short-term outcomes have improved over time since 2013, which was when the Korean Neonatal Network (KNN) was launched.

METHODS

This study used data from the annual reports of the KNN from 2013 to 2020. A total of 16,351 VLBWIs born at gestational age (GA) ≥ 22 weeks between January 1, 2013, and December 31, 2020, and who were registered in the KNN were enrolled. Serial outcomes were analyzed according to era (2013-14, 2015-16, 2017-18, and 2019-20).

RESULTS

More mothers delivered by cesarean section, had diabetes or hypertension during their pregnancy, and received antenatal steroids when analyzed by era. Fewer infants were intubated at birth and had air leaks when analyzed by era. The overall survival rate of VLBWIs between 2013 and 2020 was 87%. The rate of respiratory distress syndrome was 77% and that of bronchopulmonary dysplasia was 32% between 2013 and 2020. The rates of intraventricular hemorrhage (grade ≥ 3), periventricular leukomalacia, and sepsis decreased over time. The survival rate of infants with a GA of 26 weeks has improved serially according to era.

CONCLUSION

Since the launch of the KNN in 2013, the survival rates of infants with GA 26 weeks and short-term outcomes have improved, which implies a quality improvement in antenatal and delivery room care. Further studies on the long-term neurodevelopmental outcomes of these KNN registrants are warranted.

Short term outcomes of extremely low birth weight infants from a multicenter cohort study in Guangdong of China

With the increase in extremely low birth weight (ELBW) infants, their outcome attracted worldwide attention. However, in China, the related studies are rare. The hospitalized records of ELBW infants discharged from twenty-six neonatal intensive care units in Guangdong Province of China during 2008-2017 were analyzed. A total of 2575 ELBW infants were enrolled and the overall survival rate was 55.11%. From 2008 to 2017, the number of ELBW infants increased rapidly from 91 to 466, and the survival rate improved steadily from 41.76% to 62.02%. Increased survival is closely related to birth weight (BW), regional economic development, and specialized hospital. The incidence of complications was neonatal respiratory distress syndrome (85.2%), oxygen dependency at 28 days (63.7%), retinopathy of prematurity (39.3%), intraventricular hemorrhage (29.4%), necrotizing enterocolitis (12.0%), and periventricular leukomalacia (8.0%). Among the 1156 nonsurvivors, 90.0% of infants died during the neonatal period (≤ 28 days). A total of 768 ELBW infants died after treatment withdrawal, for reasons of economic and/or poor outcome. The number of ELBW infants is increasing in Guangdong Province of China, and the overall survival rate is improving steadily.

Preterm Labor: A Comprehensive Review of Guidelines on Diagnosis, Management, Prediction and Prevention

Importance

Preterm labor (PTL) is one of the most common and serious pregnancy complications associated with significant perinatal morbidity and mortality, as well as long-term neurologic impairment in the offspring.

Objective

The aim of this study was to review and compare the most recently published major guidelines on diagnosis, management, prediction, and prevention of this severe complication of pregnancy.

Evidence Acquisition

A descriptive review of guidelines from the National Institute for Health and Care Excellence (NICE), the World Health Organization, the American College of Obstetricians and Gynecologists, the New South Wales Government, and the European Association of Perinatal Medicine (EAPM) on PTL was carried out.

Results

There is a consensus among the reviewed guidelines that the diagnosis of PTL is based on clinical criteria, physical examination, measurement of cervical length (CL) with transvaginal ultrasound (TVUS) and use of biomarkers, although there is disagreement on the first-line diagnostic test. The NICE and the EAPM are in favor of TVUS CL measurement, whereas the New South Wales Government mentions that fetal fibronectin testing is the mainstay for PTL diagnosis. Moreover, there is consistency among the guidelines regarding the importance of treating PTL up to 34 weeks of gestation, to delay delivery for 48 hours, for the administration of antenatal corticosteroids, magnesium sulfate, and in utero transfer to higher care facility, although several discrepancies exist regarding the tocolytic drugs of choice and the administration of corticosteroids and magnesium sulfate after 34 and 30 gestational weeks, respectively. Routine cesarean delivery in case of PTL is unanimously not recommended. Finally, the NICE, the American College of Obstetricians and Gynecologists, and the EAPM highlight the significance of screening for PTL by TVUS CL measurement between 16 and 24 weeks of gestation and suggest the use of either vaginal progesterone or cervical cerclage for the prevention of PTL, based on specific indications. Cervical pessary is not recommended as a preventive measure.

Conclusions

Preterm labor is a significant contributor of perinatal morbidity and mortality with a substantial impact on health care systems. Thus, it seems of paramount importance to develop consistent international practice protocols for timely diagnosis and effective management of this major obstetric complication and subsequently improve pregnancy outcomes.

The Relationship between Antenatal Corticosteroid Administration-to-Delivery Intervals and Neonatal Respiratory Distress Syndrome and Respiratory Support

Background

Administration of antenatal corticosteroids (ACSs) is an effective strategy for managing preterm infants, which improves neonatal respiratory distress syndrome (NRDS) and attenuates the risk of neonatal mortality. However, many preterm infants are not exposed to a complete course of ACS administration, and the effects of different ACS-to-delivery intervals on NRDS and respiratory support remain unclear. Therefore, this study explored the relationship between ACS-to-birth intervals and NRDS and respiratory support in preterm infants.

Methods

In this retrospective cohort study, the preterm infants born between 240/7 and 316/7 wks of gestation were recruited from January 2015 to July 2021. All participants were categorised based on the time interval from the first ACS dose to delivery: <24 h, 1-2 d, 2–7 d, and >7 d. Multivariable logistic regression analysis examined the relationships between the ACS-to-birth interval and primary or secondary outcome while adjusting for potential confounders.

Results

Of the 706 eligible neonates, 264, 83, 292, and 67 received ACS-to-delivery intervals of <24 h, 1-2 d, 2–7 d, and >7 d, respectively. After adjusting these confounding factors, the multivariable logistic analysis showed a significantly increased risk of NRDS (aOR: 1.8, 95% CI: 1.2–2.7), neonatal mortality (aOR: 2.8, 95% CI: 1.1–6.8), the need for surfactant use (aOR: 2.7, 95% CI: 1.7–4.4), endotracheal intubation in the delivery room (aOR: 1.9, 95% CI: 1.0–3.7), and mechanical ventilation (aOR: 1.9, 95% CI: 1.1–3.4) in the ACS-to-delivery interval of <24 h group when compared with the ACS-to-birth interval of 2–7 d group.

Conclusions

Neonatal outcomes such as NRDS, neonatal mortality, the need for surfactant use, intubation in the delivery room, and the risk of mechanical ventilation are higher when the neonates are exposed to an ACS interval for less than 24 h before delivery.

Association between antenatal corticosteroids use and perinatal mortality among preterm singletons and twins in Mwanza, Tanzania: an observational study

OBJECTIVES

To examine the association between antenatal corticosteroids (ACS) use and perinatal mortality in singletons and twins delivered before 35 weeks of gestation.

DESIGN

Secondary analysis of data from an observational prospective chart review study that investigated if exposure to ACS was associated with lower rates of perinatal mortality in preterm infants.

SETTING

This study was conducted in four hospitals located in Mwanza region, Tanzania.

PARTICIPANTS

The study population included all preterm singletons and twins delivered at these hospitals between 24 weeks 0 days and 34 weeks 6 days of gestation from July 2019 to February 2020.

OUTCOME MEASURES

The primary outcome was perinatal mortality; the secondary outcome was respiratory distress syndrome (RDS).

RESULTS

The study included 844 singletons and 210 twin infants. Three hundred and fourteen singletons (37.2%) and 52 twins (24.8%) were exposed to at least one dose of ACS. Adjusted multivariate analyses revealed that among singletons' exposure to ACS was significantly associated with a lower likelihood of perinatal mortality, adjusted relative risk (aRR) 0.30 (95% CI 0.22 to 0.40) and RDS, aRR 0.92 (95% CI 0.87 to 0.97). In twin infants, exposure to ACS was associated with a reduced risk of RDS only, aRR 0.87 (95% CI 0.78 to 0.98).

CONCLUSION

The use of ACS between 24 weeks 0 days and 34 weeks 6 days of gestation in both singletons and twins in low-resource settings is associated with positive infant outcomes. No adverse effects were noted. Further research that examines the benefits of ACS for twin infants is needed.

A Critical Review of Statistical Methods for Twin Studies Relating Exposure to Early Life Health Conditions

When investigating disease etiology, twin data provide a unique opportunity to control for confounding and disentangling the role of the human genome and exposome. However, using appropriate statistical methods is fundamental for exploiting such potential. We aimed to critically review the statistical approaches used in twin studies relating exposure to early life health conditions. We searched PubMed, Scopus, Web of Science, and Embase (2011–2021). We identified 32 studies and nine classes of methods. Five were conditional approaches (within-pair analyses): additive-common-erratic (ACE) models (11 studies), generalized linear mixed models (GLMMs, five studies), generalized linear models (GLMs) with fixed pair effects (four studies), within-pair difference analyses (three studies), and paired-sample tests (two studies). Four were marginal approaches (unpaired analyses): generalized estimating equations (GEE) models (five studies), GLMs with cluster-robust standard errors (six studies), GLMs (one study), and independent-sample tests (one study). ACE models are suitable for assessing heritability but require adaptations for binary outcomes and repeated measurements. Conditional models can adjust by design for shared confounders, and GLMMs are suitable for repeated measurements. Marginal models may lead to invalid inference. By highlighting the strengths and limitations of commonly applied statistical methods, this review may be helpful for researchers using twin designs.

Association of antenatal corticosteroids with morbidity and mortality among preterm multiple gestations: meta-analysis of observational studies

OBJECTIVE

This meta-analysis aimed to assess the efficacy of antenatal corticosteroids (ACS) on morbidity and mortality among preterm multiple pregnancies.

METHODS

The PubMed, Embase, Web of Science and Cochrane Library databases were searched for studies investigating the outcomes among preterm multiple gestations following to ACS, from their inception to 1 November 2020. Two authors independently performed the study selection, risk of bias assessment and data extraction. The primary outcomes were respiratory distress syndrome (RDS) and mortality and secondary outcomes included intraventricular haemorrhage (IVH), periventricular leukomalacia (PVL), necrotising enterocolitis, retinopathy of prematurity and bronchopulmonary dysplasia. Pooled ORs were obtained using random effects models. Subgroup analyses were performed to explain heterogeneity by ACS completeness, administration-to-delivery intervals (≤7 days) and single or multicentre.

RESULTS

A total of 16 observational studies with 36 973 newborns were included in the meta-analysis. ACS treatment was associated with a reduction in RDS (OR 0.66; 95% CI 0.54 to 0.82; I2=91.4%; p<0.001), mortality (OR 0.64; 95% CI 0.50 to 0.81; I2=85.9%; p<0.001), IVH (OR 0.67; 95% CI 0.54 to 0.83; I2=77.4%; p<0.001) and PVL (OR 0.65; 95% CI 0.47 to 0.92; I2=75.5%; p<0.001). Subgroup analyses showed ACS completeness, administration-to-delivery interval and multicentre study affected these associations.

DISCUSSION

ACS may be beneficial for reducing the risks of RDS, mortality, IVH and PVL among preterm multiple gestations. The efficacy of ACS could be affected by ACS completeness and administration-to-delivery. More robust evidence on the efficacy of ACS treatment among multiple gestations is warranted.

Evaluation of the effectiveness of antenatal corticoid in preterm twin and single pregnancies: a multicenter cohort study

BACKGROUND

The effects of antenatal corticosteroids (ANSs) on twins are not well established.

OBJECTIVE

To determine the impact of ANS use according to the number of fetuses.

METHODS

Retrospective cohort study of newborns between 23 and 33 weeks of gestational age, birth weight from 400 to 1499 g, without malformations, delivered at 20 public university hospitals from 2010 to 2014.Exposed group: Received ANS (any time, any dose) and no exposed group: no received ANS. Analysis of birth conditions and clinical outcomes. Association of variables, relative risks, and 95% confidence intervals estimated from the adjustment of log-binomial regression models.

RESULTS

About 7165 premature infants were analyzed: 5167 singleton, 937 twins, and 104 triplets. Characteristics of gestations with one, two, or three fetuses not receiving ANS were similar. Reduced hemodynamic instability in single and twins gestations in the first 72 h were observed (Adj R² Twins = 0.78; 95% CI = 0.69-0.86) (Adj R² Singles = 0.79; 95% CI = 0.62-0.99). Reduced peri-intraventricular hemorrhage (Adj R² Twins = 0.54; 95% CI = 0.36-0.78) (Adj R² singles = 0.54; 95% CI = 0.36-0.78); and early sepsis reduction on single and triplex gestations (Adj R² triplex = 0.51; 95% CI = 0.27-0.94) (Adj single R² = 0.51; 95% CI = 0.27-0.94) were observed.

CONCLUSIONS

This study demonstrates ANS produces an important protective factor for severe intraventricular hemorrhage and hemodynamic instability in single and multiple pregnancies. ANS had a protective effect on death and birth conditions improvement just in single gestations. Regarding respiratory aspects was not observed the protective effect in the single or multiple gestations.

Prediction of In-Hospital Mortality After 24 Hours in Very Low Birth Weight Infants

BACKGROUND AND OBJECTIVES

The existing prediction formulas for in-hospital mortality of very low birth weight (VLBW) infants were mostly developed in the 1990s or 2000s and thus may not reflect the recently improved levels of neonatal care. We conducted this study to build a model for predicting the in-hospital mortality using perinatal factors available soon after birth.

METHODS

We gathered data on VLBW infants from the Korean Neonatal Network, a nationwide, prospective, Web-based registry that enrolled patients from 2013 to 2017. Perinatal variables that were significantly associated with mortality in univariate logistic regression or those with apparent clinical importance were included in the multivariable logistic regression model. The final formula was constructed by considering the collinearity, parsimony, goodness of fit, and clinical interpretation.

RESULTS

A total of 9248 VLBW infants were analyzed, including 1105 (11.9%) who died during hospitalization. The mean gestational age was 29.0 ± 2.9 weeks and the mean birth weight was 1096 ± 280 g. Significant variables used in the final equation included polyhydramnios, oligohydramnios, gestational age, Apgar score at 1 minute, intubation at birth, birth weight, and base excess. In internal validation, the area under the curve (AUC) for the prediction of in-hospital mortality was 0.870 and the optimism-corrected AUC was 0.867. The prediction equation revealed good discrimination and calibration in the external validation as well (AUC: 0.876).

CONCLUSIONS

The newly developed Korean Neonatal Network prediction formula for in-hospital mortality could be a useful tool in counseling by providing a reliable prediction for the in-hospital mortality of VLBW infants.

Frühgeborene an der Grenze der Lebensfähigkeit (Entwicklungsstufe S2k, AWMF-Leitlinien-Register Nr. 024/019, Juni 2020)

Redaktionskomitee Federführende Fachgesellschaft

Association of pre-pregnancy body mass index with adverse pregnancy outcome among first-time mothers

Background

Studies have reported an increased risk of adverse pregnancy outcome associated with pre-pregnancy body mass index (BMI). However, the data on such associations in urban areas of southern Chinese women is limited, which drive us to clarify the associations of pre-pregnancy BMI and the risks of adverse pregnancy outcomes (preterm birth (PTB) and low birth weight (LBW)) and maternal health outcomes (gestational hypertension and cesarean delivery).

Methods

We performed a hospital-based case-control study including 3,864 Southern Chinese women who gave first birth to a live singleton infant from January 2015 to December 2015. PTB was stratified into three subgroups according to gestational age (extremely PTB, very PTB and moderate PTB). Besides, we combined birth weight and gestational age to dichotomise as being small for gestational age (SGA, less than the tenth percentile of weight for gestation) and non-small for gestational age (NSGA, large than the tenth percentile of weight for gestation), gestational week was also classified into categories of term, 34-36 week and below 34 week.. We then divided newborns into six groups: (1) term and NSGA; (2) 34–36 week gestation and NSGA; (3) below 34 week gestation and NSGA; (4) term and SAG; (5) 34–36 week gestation and SAG; (6) below 34 week gestation and SAG. Adjusted logistic regression models was used to estimate the odds ratios of adverse outcomes.

Results

Underweight women were more likely to give LBW (AOR = 1.44, 95% CI [1.11–1.89]), the similar result was seen in term and SAG as compared with term and NSAG (AOR = 1.78, 95% CI [1.45–2.17]), whereas underweight was significantly associated with a lower risk of gestational hypertension (AOR = 0.45, 95% CI [0.25–0.82) and caesarean delivery (AOR = 0.74, 95% CI [0.62–0.90]). The risk of extremely PTB is relatively higher among overweight and obese mothers in a subgroup analysis of PTB (AOR = 8.12, 95% CI [1.11–59.44]; AOR = 15.06, 95% CI [1.32–172.13], respectively). Both maternal overweight and obesity were associated with a greater risk of gestational hypertension (AOR = 1.71, 95% CI [1.06–2.77]; AOR = 5.54, 95% CI [3.02–10.17], respectively) and caesarean delivery (AOR = 1.91, 95% CI [1.53–2.38]; AOR = 1.85, 95% CI [1.21–2.82], respectively).

Conclusions

Our study suggested that maternal overweight and obesity were associated with a significantly higher risk of gestational hypertension, caesarean delivery and extremely PTB. Underweight was correlated with an increased risk of LBW and conferred a protective effect regarding the risk for gestational hypertension and caesarean delivery for the first-time mothers among Southern Chinese.

Mortality rate-dependent variations in antenatal corticosteroid-associated outcomes in very low birth weight infants with 23-34 weeks of gestation: A nationwide cohort study

Antenatal corticosteroid (ACS) administration has been known as one of the most effective treatment in perinatal medicine, but the beneficial effects of ACS may vary not only gestational age, but also the quality of perinatal and neonatal care of the institution. This nationwide cohort study of the Korean Neonatal Network (KNN) data was consisted of <1,500g infants born at 23–34 weeks at 67 KNN hospitals between 2013 and 2017. The 9,142 eligible infants were assigned into two groups–group 1 and 2 <50% and ≥50% mortality rate, respectively, for 23–24 weeks’ gestation–reflecting the quality of perinatal and neonatal care. Each group of infants were further stratified into 23–24, 25–26, 27–28, and 29–34 weeks of gestation age. Despite comparable ACS usage between group 1 (82%) and group 2 (81%), the benefits of ACS were only observed in group 1. In the multivariable analyses, infants of group 1 showed significant decrease in mortality and IVH at gestational age 23–24 weeks with ACS use, and the decrease was also seen in early-onset sepsis and respiratory distress syndrome at gestational age of 29–34 weeks while there were no significant decrease in group 2. In this study the overall data was congruent with the previous findings stating that ACS use decreases mortality and morbidity. These results indicate that the improved mortality of infants at 23–24 weeks’ gestation reflects the quality improvement of perinatal and neonatal intensive care, which is a prerequisite to the benefits of ACS.

Determinants and effects of fluid status changes in caesarean delivered neonates

AIM

Evidence suggests that caesarean section is associated with a reduced placental transfusion and poor iron-related haematological indices, both in cord and peripheral blood, compared with vaginal delivery. We assessed determinants and effects of fluid status changes on placental transfusion in neonates delivered by elective (ElCD) and emergency (EmCD) caesarean section.

METHODS

Placental transfusion was estimated by ∆ haematocrit (Hct) increase from birth to 48 hours of life, accounting for contemporaneous ∆ body weight decrease, in 143 women/infant pairs, 62 who underwent ElCD and 81 EmCD, respectively.

RESULTS

Cord blood Hct levels at birth of ElCS neonates were significantly lower than those of EmCD neonates (44.58 + 4.87vs 49.93 + 4.29, P = .01). At 48 hours of life, capillary heel Hct levels of ElCD and of EmCD neonates were comparable. ElCD had a higher ∆ body weight decrease (ElCD -7.25 ± 1.74% vs EmCD -6.31 ± 2.34% [P: .011]) and ∆ Hct increase ([ElCD + 5.93 ± 4.92 vs EmCD + 3.59 ± 5.29, [P: .011]). In a linear regression model analysis, gestational age in ElCD neonates had a significant effect on the differences in arterial cord blood Hct, body weight at birth and body weight decrease at 48 hours after birth.

CONCLUSION

Early-term surgical delivery is a determinant of transient dilutional anaemia in ElCD neonates, lacking neuroendocrine response of labour and delivery.

Strategies for optimising antenatal corticosteroid administration for women with anticipated preterm birth

BACKGROUND

Preterm birth is a serious and common pregnancy complication. The burden is particularly high in low- and middle-income countries where available care is often inadequate to ensure preterm newborn survival. Administration of antenatal corticosteroids (ACS) is recommended as the standard care for the management of women at risk of imminent preterm birth but its coverage varies globally. Efforts to improve preterm newborn survival have largely been focused on optimising the coverage of ACS use. However, the benefits and harms of such strategies are unclear.

OBJECTIVES

To determine the relative benefits and risks of individual patient protocols, health service policies, educational interventions or other strategies which aim to optimise the use of ACS for anticipated preterm birth.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (26 September 2019), and reference lists of retrieved studies.

SELECTION CRITERIA

We planned to include randomised controlled trials (RCTs), randomised at individual or cluster level, and quasi-randomised trials that assessed strategies to optimise (either by increasing or restricting) the administration of ACS compared with usual care amongst women at risk of preterm birth. Our primary outcomes were perinatal death and a composite outcome of offspring mortality and early or late neurodevelopmental morbidity.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion. All three review authors independently extracted data and assessed risk of bias. We used narrative synthesis to analyse results, as we were unable to pool data from the included studies. We assessed the certainty of evidence using the GRADE approach.

MAIN RESULTS

We included three cluster-RCTs, all assessing the effects of a multifaceted strategy aiming to promote the use of ACS among women at risk of preterm birth. We did not identify any trials assessing strategies to restrict the use of ACS versus usual care. Two of the included trials assessed use of ACS in high-resource hospital settings. The third trial, the Antenatal Corticosteroid Trial (ACT) was a multi-site trial conducted in rural and semi-urban settings of six low- and middle-income countries in South Asia, sub-Saharan Africa and Central and South America. In two trials, promoting the use of ACS resulted in increased use of ACS, whereas one trial did not find a difference in the rate of ACS administration compared to usual care. Whilst we included three studies, we were unable to pool the data in meta-analysis due to outcomes not being reported across all studies, or outcome results being reported in different ways. The main source of data in this review is from the ACT trial. We assessed the ACT trial as high risk for performance and selective reporting bias. In the protocol for this review, we planned to report all settings and subgroup by low-middle versus high-income countries; these planned analyses were not possible in this version of the review, although adding further studies in future updates may allow us to carry out planned subgroup analyses. The ACT trial was conducted in low-resource settings and reported data on appropriate ACS treatment and inappropriate ACS treatment. Although a strategy of promoting the administration of ACS compared to routine care may increase appropriate ACS treatment (RR 4.34, 95%CI 3.59 to 5.25; 1 study; n = 4389; low-certainty evidence), it may also increase inappropriate ACS treatment (RR 9.11 95%CI 8.04 to 10.33, 1 study, n = 89,237; low-certainty evidence). In low-resource settings, a strategy of promoting the administration of ACS probably increases population level perinatal death by 3 per 1000 infants (risk ratio (RR) 1.11, 95% confidence interval (CI) 1.04 to 1.19; 1 study; n = 100,705; moderate-certainty evidence); stillbirth by 2 per 1000 infants (RR 1.11, 95% CI 1.02 to 1.21; 1 study; n = 100,705; moderate-certainty evidence); and neonatal death before 28 days by 2 per 1000 infants (RR 1.12, 95% CI 1.02 to 1.23; 1 study; n = 100,705; moderate-certainty evidence); may increase the risk for 'suspected' maternal infection or inflammation (RR 1.49, 95% CI 1.32 to 1.68; 1 study; n = 99,742; low-certainty evidence); and make little or no difference to the risk of maternal mortality (RR 1.11, 95% CI 0.64 to 1.92; 1 study; n = 99,742; low-certainty evidence) compared to routine care. Included trials did not report on the composite outcomes offspring mortality, early neurodevelopmental morbidity or late neurodevelopmental morbidity; and offspring mortality or severe neonatal morbidity.

AUTHORS' CONCLUSIONS

In low-resource settings, a strategy of actively promoting the use of ACS in women at risk of preterm birth may increase ACS use in the target population, but may also carry a substantial risk of unnecessary exposure of ACS to women in whom ACS is not indicated. At the population level, these effects are probably associated with increased risks of stillbirth, perinatal death, neonatal death before 28 days, and maternal infection. The findings of this review support a more conservative approach to clinical protocols and clinical decision-making particularly in low-resource settings, along the lines of the World Health Organization's ACS 2015 recommendations, which take into account both the established clinical efficacy of ACS when used in the correct situation and context, and the possibility of important adverse effects when certain conditions are not met. Given the unanticipated results of the ACT trial, further research on strategies to optimise the use of ACS in low-resource settings is justified.

Mortality and Neurodevelopmental Outcomes in the Heart Rate Characteristics Monitoring Randomized Controlled Trial

OBJECTIVE

To test whether the composite outcome of death or neurodevelopmental impairment (NDI) at 18-22 months corrected age for infants ≤1000 g at birth is decreased by continuous monitoring of heart rate characteristics during neonatal intensive care.

STUDY DESIGN

We studied a subset of participants enrolled in a multicenter randomized trial of heart rate characteristics monitoring. Survivors were evaluated at 18-22 months corrected age with a standardized neurologic examination and the Bayley Scales of Infant Development-III (BSID-III). NDI was defined as Gross Motor Function Classification System of >2 (moderate or severe cerebral palsy), BSID-III language or cognitive scores of <70, severe bilateral hearing impairment, and/or bilateral blindness.

RESULTS

The composite outcome, death or NDI, was obtained for 628 of 884 study infants (72%). The prevalence of this outcome was 44.4% (136/306) among controls (infants randomized to heart rate characteristics monitored but not displayed) and 38.9% (125/322) among infants randomized to heart rate characteristics monitoring displayed (relative risk, 0.87; 95% CI, 0.73-1.05; P = .17). Mortality was reduced from 32.0% (99/307) among controls to 24.8% (81/326) among monitoring displayed infants (relative risk, 0.75; 95% CI, 0.59 to 0.97; P = .028). The composite outcomes of death or severe CP and death or mildly low Bayley cognitive score occurred less frequently in the displayed group (P < .05).

CONCLUSIONS

We found no difference in the composite outcome of death or NDI for extremely preterm infants whose heart rate characteristics were and were not displayed during neonatal intensive care. Two outcomes that included mortality or a specific NDI were less frequent in the displayed group.

Care Practices, Morbidity and Mortality of Preterm Neonates in China, 2013-2014: a Retrospective study

This retrospective cohort study aimed to investigate the prevalence, morbidity, mortality and the maternal/neonatal care of preterm neonates and the perinatal risk factors for mortality. We included data on 13,701 preterm neonates born in 15 hospitals for the period 2013–2014 in China. Results showed a prevalence of preterm neonates of 9.9%. Most infants at 24–27 weeks who survived more than 12 hours were mechanically ventilated (56.1%). Few infants born before 28 weeks received CPAP without first receiving mechanical ventilation (8.1%). Few preterm neonates received antenatal steroid(35.8% at 24–27 weeks, 57.9% at 28–31 weeks, 57.0% at 32–33 weeks and 32.7% at 34–36 weeks). Overall mortality was 1.9%. Most of the deaths at 24–27 weeks of gestation occurred within 12 hours after birth, accounting for 68.1%(32/47), and within 12–72 hours after birth at 28–36 weeks of gestation, accounting for 47.4%(99/209). Rates of survival to discharge increased from 68.2% at 24–27 weeks, 93.3% at 28–31 weeks, 99.2% at 32–33 weeks to 99.4% at 34–36 weeks. The smaller of the GA, there was a greater risk of morbidities due to prematurity. Preterm birth weight (OR = 0.407, 95% CI 0.346–0.478), antenatal steroid (OR = 0.680, 95% CI 0.493–0.938), and neonatal asphyxia (OR = 3.215, 95% CI 2.180–4.741) proved to significantly influence the odds of preterm neonatal death. Overall, our results support that most of the preterm neonates at 28–36 weeks of gestation survived without major morbidity. Rate of survival of GAs less than 28 weeks was still low. Maternal and infant care practices need to be improved in the very preterm births.

No. 364-Antenatal Corticosteroid Therapy for Improving Neonatal Outcomes

OBJECTIVE

To assess the benefits and risks of antenatal corticosteroid therapy for women at risk of preterm birth or undergoing pre-labour Caesarean section at term and to make recommendations for improving neonatal and long-term outcomes.

OPTIONS

To administer or withhold antenatal corticosteroid therapy for women at high risk of preterm birth or women undergoing pre-labour Caesarean section at term.

OUTCOMES

Perinatal morbidity, including respiratory distress syndrome, intraventricular hemorrhage, bronchopulmonary dysplasia, infection, hypoglycemia, somatic and brain growth, and neurodevelopment; perinatal mortality; and maternal morbidity, including infection and adrenal suppression.

INTENDED USERS

Maternity care providers including midwives, family physicians, and obstetricians.

TARGET POPULATION

Pregnant women.

EVIDENCE

Medline, PubMed, Embase, and the Cochrane Library were searched from inception to September 2017. Medical Subject Heading (MeSH) terms and key words related to pregnancy, prematurity, corticosteroids, and perinatal and neonatal mortality and morbidity were used. Statements from professional organizations including that of the National Institutes of Health, the American College of Obstetricians and Gynecologists, the Society for Maternal Fetal Medicine, the Royal College of Obstetricians and Gynaecologists, and the Canadian Pediatric Society were reviewed for additional references. Randomized controlled trials conducted in pregnant women evaluating antenatal corticosteroid therapy and previous systematic reviews on the topic were eligible. Evidence from systematic reviews of non-experimental (cohort) studies was also eligible.

VALIDATION METHODS

This Committee Opinion has been reviewed and approved by the Maternal-Fetal Medicine Committee of the SOGC and approved by SOGC Council.

BENEFITS, HARMS, AND/OR COSTS

A course of antenatal corticosteroid therapy administered within 7 days of delivery significantly reduces perinatal morbidity/mortality associated with preterm birth between 24 + 0 and 34 + 6 weeks gestation. When antenatal corticosteroid therapy is given more than 7 days prior to delivery or after 34 + 6 weeks gestation, the adverse effects may outweigh the benefits. Evidence on long-term effects is scarce, and potential neurodevelopment harms are unquantified in cases of late preterm, term, and repeated exposure to antenatal corticosteroid therapy.

GUIDELINE UPDATE

Evidence will be reviewed 5 years after publication to evaluate the need for a complete or partial update of the guideline. If important evidence is published prior to the 5-year time point, an update will be issued to reflect new knowledge and recommendations.

SPONSORS

The guideline was developed with resources provided by the Society of Obstetricians and Gynaecologists of Canada with support from the Canadian Institutes of Health Research (APR-126338).

SUMMARY STATEMENTS

RECOMMENDATIONS: Gestational Age Considerations Agents, Dosage, Regimen, and Target Timing Subpopulations and Special Consideration.

Neurodevelopmental disorders among term infants exposed to antenatal corticosteroids during pregnancy: a population-based study

OBJECTIVE

An increasing proportion of fetuses are exposed to antenatal corticosteroids (ACS). Despite their immediate beneficial effects, the long-term safety of ACS has been an ongoing source of concern. In the current study, we assessed the likelihood of neurodevelopmental problems among term infants exposed to ACS earlier in pregnancy compared with non-exposed term infants.

DESIGN

Retrospective cohort study (2006-2011). Median duration of follow-up was 7.8 (IQR 6.4-9.2) years.

SETTING

Population-based study, Ontario, Canada.

PARTICIPANTS

All live singleton infants born at term (≥37^0/7 weeks gestation) (n=529 205).

EXPOSURE

ACS during pregnancy.

PRIMARY AND SECONDARY OUTCOME MEASURES

A composite of diagnostic or billing codes reflecting proven or suspected neurodevelopmental problems during childhood including audiometry testing, visual testing or physician service claim with a diagnosis code related to a suspected neurocognitive disorder.

RESULTS

At 5 years of age, the cumulative rate for the primary outcome was higher among infants exposed to ACS compared with non-exposed infants: 61.7% (3346/5423) vs 57.8% (302 520/523 782), respectively (p<0.001; number needed to harm (NNH)=25, 95% CI 19 to 38; adjusted HR (aHR) 1.12, 95% CI 1.08 to 1.16). Similar findings were observed for each of the individual components of the primary outcome: 15.3% vs 12.7% for audiometry testing (p<0.001; NNH=39, 95% CI 29 to 63; aHR 1.18, 95% CI 1.11 to 1.25); 45.4% vs 43.5% for visual testing (p=0.006; NNH=54, 95% CI 31 to 200; aHR 1.08, 95% CI 1.04 to 1.12) and 25.8% vs 21.6% for suspected neurocognitive disorder (p<0.001; NNH=24, 95% CI 19 to 33; aHR 1.16, 95% CI 1.10 to 1.21).

CONCLUSIONS

We found an association among term infants between exposure to ACS during pregnancy and healthcare utilisation during childhood related to suspected neurocognitive and neurosensory disorders.

Early prediction of spontaneous Patent Ductus Arteriosus (PDA) closure and PDA-associated outcomes: a prospective cohort investigation

BACKGROUND

Patent ductus arteriosus (PDA), the most commonly diagnosed cardiovascular condition in preterm infants, is associated with increased mortality and harmful long-term outcomes (chronic lung disease, neurodevelopmental delay). Although pharmacologic and/or interventional treatments to close PDA likely benefit some infants, widespread routine treatment of all preterm infants with PDA may not improve outcomes. Most PDAs close spontaneously by 44-weeks postmenstrual age; treatment is increasingly controversial, varying markedly between institutions and providers. Because treatment detriments may outweigh benefits, especially in infants destined for early, spontaneous PDA closure, the relevant unanswered clinical question is not whether to treat all preterm infants with PDA, but whom to treat (and when). Clinicians cannot currently predict in the first month which infants are at highest risk for persistent PDA, nor which combination of clinical risk factors, echocardiographic measurements, and biomarkers best predict PDA-associated harm.

METHODS

Prospective cohort of untreated infants with PDA (n=450) will be used to predict spontaneous ductal closure timing. Clinical measures, serum (brain natriuretic peptide, N-terminal pro-brain natriuretic peptide) and urine (neutrophil gelatinase-associated lipocalin, heart-type fatty acid-binding protein) biomarkers, and echocardiographic variables collected during each of first 4 postnatal weeks will be analyzed to identify those associated with long-term impairment. Myocardial deformation imaging and tissue Doppler imaging, innovative echocardiographic techniques, will facilitate quantitative evaluation of myocardial performance. Aim1 will estimate probability of spontaneous PDA closure and predict timing of ductal closure using echocardiographic, biomarker, and clinical predictors. Aim2 will specify which echocardiographic predictors and biomarkers are associated with mortality and respiratory illness severity at 36-weeks postmenstrual age. Aim3 will identify which echocardiographic predictors and biomarkers are associated with 22 to 26-month neurodevelopmental delay. Models will be validated in a separate cohort of infants (n=225) enrolled subsequent to primary study cohort.

DISCUSSION

The current study will make significant contributions to scientific knowledge and effective PDA management. Study results will reduce unnecessary and harmful overtreatment of infants with a high probability of early spontaneous PDA closure and facilitate development of outcomes-focused trials to examine effectiveness of PDA closure in "high-risk" infants most likely to receive benefit.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03782610. Registered 20 December 2018.

Importance of early elevated maternal HbA1c levels in identifying adverse fetal and neonatal events

AIMS

The aims of this study were to explore factors that associated with gestational diabetes mellitus (GDM), and to determine the relationship between early maternal HbA1c levels and adverse fetal or neonatal events, and to determine an optimal maternal glucose testing method in order to decrease the potential health risk for their offspring.

METHODS

From December 2015 to May 2016, a total of 6744 pregnant women were enrolled from Shanghai First Maternal and Infant Hospital affiliated to Tongji University prospectively in the nested case-control study. Each GDM case was matched with a healthy pregnant woman and followed up. Outcome analyses were conducted between GDM case and control groups, as well as elevated and normal maternal HbA1c levels, respectively.

RESULTS

A total of 1836 women were included in the adverse fetal and neonatal events examination. For pregnant women with early HbA1c ≥ 5.2%, the adjusted risk ratios (RR) of respiratory distress syndrome (RDS), pneumonia and jaundice were 4.37 (95%CI 1.54-12.35), 2.03 (95%CI 1.24-3.33) and 1.49 (95%CI 1.01-2.20), respectively. After treatments, the frequency for the majority of events in GDM group was similar to that of healthy pregnant women. Moreover, the area under the curve (AUC) of early maternal HbA1c in predicting potential RDS is 0.734. HbA1c ≤ 4.9% excluded for RDS.

CONCLUSIONS

Compared with women with normal HbA1c, those with an early elevated HbA1c level were more likely to develop adverse events, including RDS, pneumonia and jaundice. Early HbA1c testing can be used as an auxiliary method identifying potential RDS.

Iron Metabolism and Brain Development in Premature Infants

Iron is important for a remarkable array of essential functions during brain development, and it needs to be provided in adequate amounts, especially to preterm infants. In this review article, we provide an overview of iron metabolism and homeostasis at the cellular level, as well as its regulation at the mRNA translation level, and we emphasize the importance of iron for brain development in fetal and early life in preterm infants. We also review the risk factors for disrupted iron metabolism that lead to high risk of developing iron deficiency and subsequent adverse effects on neurodevelopment in preterm infants. At the other extreme, iron overload, which is usually caused by excess iron supplementation in iron-replete preterm infants, might negatively impact brain development or even induce brain injury. Maintaining the balance of iron during the fetal and neonatal periods is important, and thus iron status should be monitored routinely and evaluated thoroughly during the neonatal period or before discharge of preterm infants so that iron supplementation can be individualized.

Neonatal outcomes of antenatal corticosteroids in preterm multiple pregnancies compared to singletons

BACKGROUND

Antenatal corticosteroids (ACS) during preterm labour reduce neonatal mortality and morbidity. Evidence on preterm multiple pregnancies is limited and contradictory.

OBJECTIVE

Compare the effect of ACS on very low birth weight infant's (VLBW) mortality and morbidity among singleton and multiple pregnancies.

STUDY DESIGN

Retrospective cohort study, employing prospectively collected data, of infants 23 to 34 weeks' gestation and 500 to 1500 g born at the Neocosur Neonatal Network centers during 2007-2016. Neonatal outcomes were compared among singleton and multiple pregnancies exposed to at least one dose of ACS to those not exposed using logistic regression analyses controlled for birthweight, gestational age, sex, small for gestational age (SGA) and mode of delivery.

RESULTS

A total of 13,864 infants were studied; 2948 multiple (21.3%) and 10,904 singleton pregnancies (78.7%). Overall, 11,218 (81.4%) received at least one dose of ACS with a significant reduction in the risk of death, RDS and grade III or IV IVH compared to those not exposed. Both singleton and multiple pregnancies exposed to ACS showed similar reduced risk of death (aRR 0.41 [95% CI, 0.36-0.47] vs. aRR 0.46 [95% CI, 0.34-0.64]). However, ACS were not associated with reduced odds of RDS (aRR 0.89 [95% CI, 0.66-1.23]) or grade III or IV IVH (aRR 0.99 [95% CI, 0.67-1.48]) in multiple pregnancies.

CONCLUSION

The benefit of administration of at least one dose of ACS in VLBW multiple and singleton pregnancies is comparable in terms of death. However, ACS showed no relevant impact in short-term morbidity in multiple pregnancies.

Exposure to antenatal corticosteroids and reduced respiratory sinus arrhythmia in adult survivors of extremely low birth weight

Purpose/aim: Antenatal corticosteroid (ACS) therapy has dramatically increased survival rates among extremely low birth weight (ELBW) infants. However, the long-term effects of ACS on autonomic nervous system function have not been explored. Using the world's oldest longitudinally followed cohort of ELBW infants we compared respiratory sinus arrhythmia (RSA) among ELBW survivors whose mothers received ACS (ELBW-S), those who did not (ELBW-NS) and normal birth weight (NBW) controls in their 20 and 30 s. Methods: Resting electrocardiogram (ECG) was recorded from ELBW-S (n = 28), ELBW-NS (n = 36), and matched NBW controls (n = 79) at 22-26 and 29-36 years. Resting RSA was compared across groups via analyses of covariance (ANCOVA), adjusting for sex, medication use, postnatal steroid exposure and the presence of chronic health conditions. RSA was also compared across assessments for each group. Results: At 29-36 years, resting RSA in ELBW-S was significantly lower than in NBW controls. RSA in the ELBW-NS group was intermediate between ELBW-S and NBW groups. Although the ELBW-S group also showed nominally reduced RSA compared to NBW controls at the 22-26-year visit, this difference was not statistically significant. Conclusions: ELBW survivors exposed to ACS had lower RSA than NBW controls during their 30 s, suggestive of a decline in parasympathetic input to heart. ELBW survivors who received ACS may be particularly vulnerable to cardiovascular problems in later life.

[Antenatal corticosteroids and incidence of neonatal respiratory distress after elective caesarean section in late preterm and term neonates]

INTRODUCTION

Birth by elective caesarean section in late preterm and early term newborn increases the risk of respiratory distress. Administration of antenatal corticosteroids in these cases could reduce the respiratory distress and its severity.

OBJECTIVES

To determine the influence of antenatal corticosteroids use in elective caesarean sections in the respiratory distress of the newborn from 35+0 to 38+6 weeks of gestational age.

PATIENTS AND METHODS

Retrospective analytical study of caesarean sections from 35+0 to 38+6 gestational age was conducted in a tertiary hospital from January 2013 to April 2017. Data were collected from medical records of pregnant women and newborns after an implementation of new protocol of betamethasone administration to these elective caesarean sections. Analysis was performed on 2newborn subgroups: preterm newborn (PTN) 35-36 gestational age and term (TN) 37-38 weeks.

RESULTS

A total of 208 elective caesarean sections were performed in the study period. Corticosteroids were administered in 97 (46.6%) of cases. The percentage of respiratory distress was higher in the group of preterm newborn compared to term newborn (29% vs. 8.8%, P<.001) and in term newborn higher at a lower gestational age. Between treated with corticosteroids or not, no significant differences were found in the treated and non-treated in the development of respiratory distress (PTN 30 vs. 30%, TN 9.1 vs. 6.9%, P=.6).

CONCLUSIONS

No statistically significant differences were found in this study in favour of the administration of an antenatal dose of betamethasone in the reduction of respiratory distress in the elective caesarean sections from 35+0 to 38+6 gestational age. The delay in the indication of elective caesarean sections, whenever possible, could help reduce the incidence of newborn respiratory distress.

N° 364 - La Corticothérapie Prénatale Pour Améliorer Les Issues Néonatales

OBJECTIF

Évaluer les avantages et les risques de la corticothérapie prénatale chez les femmes qui présentent un risque d'accouchement prématuré ou qui subissent une césarienne à terme avant début de travail, et formuler des recommandations visant l'amélioration des issues néonatales et des issues à long terme.

OPTIONS

Administrer ou ne pas administrer une corticothérapie prénatale aux femmes qui présentent un risque élevé d'accouchement prématuré ou qui subissent une césarienne avant travail à terme. RéSULTATS: Morbidité périnatale, notamment le syndrome de détresse respiratoire, l'hémorragie intraventriculaire, la dysplasie bronchopulmonaire, l'infection, l'hypoglycémie, ainsi que les troubles de la croissance somatique et cérébrale et du neurodéveloppement; mortalité périnatale; et morbidité maternelle, notamment l'infection et la suppression surrénalienne.

UTILISATEURS CIBLES

Fournisseurs de soins de maternité, notamment les sages-femmes, les médecins de famille et les obstétriciens.

POPULATION CIBLE

Femmes enceintes. ÉVIDENCE: Nous avons interrogé les bases de données Medline, PubMed et Embase ainsi que la Bibliothèque Cochrane, de leur création au mois de septembre 2017. Nous nous sommes servis de Medical Subjet Headings (MeSH) et de mots clés en lien avec la grossesse, la prématurité, les corticostéroïdes ainsi que la mortalité et la morbidité périnatales et néonatales. Nous avons également consulté les déclarations d'organismes professionnels tels que les National Institutes of Health, l'American College of Obstetricians and Gynecologists, la Society for Maternal-Fetal Medicine, le Royal College of Obstetricians and Gynaecologists et la Société canadienne de pédiatrie pour obtenir des références additionnelles. Les essais cliniques randomisés évaluant la corticothérapie prénatale menés sur des femmes enceintes et les revues systématiques antérieures sur le sujet étaient admissibles, tout comme les données venant de revues systématiques d'études non expérimentales (études de cohorte).

VALEURS

La présente opinion de comité a été révisée et approuvée par le Comité de médecine fœto-maternelle de la SOGC, et approuvée par le Conseil de la SOGC. AVANTAGES, INCONVéNIENTS ET COûTS: L'administration d'une corticothérapie prénatale dans les sept jours précédant l'accouchement réduit significativement la morbidité et la mortalité périnatales associées à la naissance prématurée survenant entre 24+0 et 34+6 semaines de grossesse. Si la corticothérapie prénatale est administrée plus de sept jours avant l'accouchement ou après 34+6 semaines de grossesse, les effets indésirables peuvent surpasser les avantages. Les données probantes sur l'impact à long terme de la corticothérapie prénatale sont rares. Par ailleurs, les effets neurodéveloppementaux néfastes potentiels de l'exposition répétée à la corticothérapie prénatale ou de l'administration de corticostéroïdes en période préterme tardive ou à terme n'ont pas été quantifiés. MIS-à-JOUR à LA DIRECTIVE: Une revue des données probantes sera menée cinq ans après la publication de la présente directive clinique afin d'évaluer si une mise à jour complète ou partielle s'impose. Si de nouvelles données probantes importantes sont publiées avant la fin de ces cinq ans, une mise à jour tenant compte des nouvelles connaissances et recommandations sera publiée.

COMMANDITAIRES

La présente directive clinique a été élaborée à l'aide de ressources fournies par la Société des obstétriciens et gynécologues du Canada et avec l'appui des Instituts de recherche en santé du Canada (APR-126338). MOTS CLéS: Corticothérapie prénatale, maturation fœtale, prématurité, période préterme tardive, césarienne avant travail DÉCLARATION SOMMAIRES: RECOMMANDATIONS: Considérations relatives à l'âge gestationnel.

Antenatal Corticosteroids: Who Should We Be Treating?

Antenatal corticosteroids remain one of the crucial interventions in those at risk for imminent preterm birth. Therapeutic benefits include reducing major complications of prematurity such as respiratory distress syndrome, intraventricular hemorrhage, and necrotizing enterocolitis, as well as an overall decrease in neonatal deaths. Optimal reductions in neonatal morbidity and mortality require a thoughtful review of the timing of administration. In addition, a thorough understanding is required of which patients maximally benefit from this intervention in the management and counseling of those at risk for preterm birth.

Association of induced abortion with preterm birth risk in first-time mothers

Women who have previously had an induced abortion (IA) before their first birth have been associated with preterm birth (PTB). However, previous studies on the PTB are inconsistent. Therefore, the aim of this study was to clarify the association between IA and PTB and low birth weight (LBW) for first-time mothers. A total of 3,684 Southern Chinese women who gave birth for the first time to a live singleton infants were recruited between January 2015 and December 2015 in the province of Guangdong, China. Univariable and multivariable analyses were conducted to determine whether IA was associated with PTB and LBW. Previous IA was not associated with increased risks of PTB or LBW, adjusted odds ratios were 0.80 (95% CI = 0.53 to 1.20) and 0.86 (95% CI = 0.57 to 1.31), respectively. Additionally, no significant associations were observed for infants born at before 37, before 32, and before 28 gestational weeks. And no significant associations were also observed for LBW measuring lower than 2500 grams and also measuring lower than 1500 grams. Our study suggested that a previous IA, as compared with women who reported no previous IA, does not increase the risk of PTB or LBW in subsequent pregnancy for the first-time mothers among Southern Chinese women.

Extremely preterm fetal sheep lung responses to antenatal steroids and inflammation

BACKGROUND

The efficacy of antenatal steroids for fetal lung maturation in the periviable period is not fully understood.

OBJECTIVE

We sought to determine the lung maturational effects of antenatal steroids and inflammation in early gestation sheep fetuses, similar to the periviable period in human beings.

STUDY DESIGN

Date-mated ewes with singleton fetuses were randomly assigned to 1 of 4 treatment groups (n = 8/group): (1) maternal intramuscular injection of betamethasone; (2) intraamniotic lipopolysaccharide; (3) betamethasone + lipopolysaccharide; and (4) intraamniotic + intramuscular saline (controls). Fetuses were delivered surgically 48 hours later at 94 days' gestation (63% term gestation) for comprehensive evaluations of lung maturation, and lung and systemic inflammation.

RESULTS

Relative to controls, first, betamethasone increased the fetal lung air space to mesenchymal area ratio by 47% but did not increase the messenger RNAs for the surfactant proteins-B and -C that are important for surfactant function or increase the expression of pro-surfactant protein-C in the alveolar type II cells. Second, betamethasone increased expression of 1 of the 4 genes in surfactant lipid synthetic pathways. Third, betamethasone increased genes involved in epithelium sodium channel transport, but not sodium-potassium adenosine triphosphatase or Aquaporin 5. Fourth, lipopolysaccharide increased proinflammatory genes in the lung but did not effectively recruit activated inflammatory cells. Last, betamethasone incompletely suppressed lipopolysaccharide-induced lung inflammation. In the liver, betamethasone when given alone increased the expression of serum amyloid A3 and C-reactive protein messenger RNAs.

CONCLUSION

Compared the more mature 125-day gestation sheep, antenatal steroids do not induce pulmonary surfactants during the periviable period, indicating a different response.

Efficacy of Antenatal Corticosteroid Treatment on Neurodevelopmental Outcome according to Head Circumference at Birth

BACKGROUND

There are concerns about the efficacy of antenatal corticosteroid treatment (ACT) in the growth-restricted fetus.

OBJECTIVE

To evaluate the effect of ACT on neurodevelopmental outcome at 2 years of corrected age according to the z score of birth head circumference (ZS HC) in a large prospective cohort of preterm infants.

METHODS

This study was conducted as a population-based, prospective, multicenter study, including 4,965 infants born between 24 and 33 weeks' gestation and whose status regarding ACT and the measurement of head circumference at birth were available. They were evaluated at 2 years of corrected age to assess neurological outcome. Three approaches were considered to estimate the effect of ACT on neurodevelopment: (i) logistic regression with adjustment on propensity score, (ii) weighted logistic regression using the inverse probability of treatment weighting method, and (iii) 1:1 matching of gestational age, ZS HC, and propensity score between treated and nontreated infants.

RESULTS

ACT was documented in 60% of infants. Three groups of infants were considered according to their ZS HC: between -3 and -1 standard deviation (SD), -1 and +1 SD, and +1 and +3 SD, respectively. ACT was associated with a significant improvement of neurodevelopmental outcome only for infants with an ZS HC of between +1 and +3 SD (adjusted OR 1.72; 95% CI 1.06-2.79). Moreover, ORs estimated in the -3 to -1 and +1 to +3 categories were significantly different.

CONCLUSION

We found beneficial effects of ACT on neurodevelopmental outcomes at 2 years of corrected age only in preterm infants with a ZS HC >1 SD.

Risk of Mortality into Adulthood According to Gestational Age at Birth

OBJECTIVES

To quantify the independent risks of neonatal (0-28 days), postneonatal (29-364 days), 1- to 5- and 6- to 30-year mortality by gestational age and investigate changes in survival over time in an Australian birth cohort.

STUDY DESIGN

Maternal and birth related Western Australian population data (1980-2010) were linked to the state mortality data using a retrospective cohort study design involving 722 399 live-born singletons infants.

RESULTS

When compared with 39- to 41-week born infants, the adjusted risk ratio for neonatal mortality was 124.8 (95% CI 102.9-151.3) for 24-31 weeks of gestation, 3.4 (95% CI 2.4-4.7) for 35-36 weeks of gestation, and 1.4 (95% CI 1.1-1.8) for 37-38 weeks of gestation. For 24-31 weeks of gestation infants, the adjusted hazard ratio for postneonatal mortality (29-364 days) was 13.9 (95% CI 10.9-17.6), for 1- to 5-year mortality 1.4 (95% CI 0.7-3.0) and for 6- to 30-year mortality 1.3 (95% CI 0.8-2.3). The risk of neonatal and postneonatal mortality for those born preterm decreased over time.

CONCLUSIONS

In Western Australia, late preterm and early term infants experienced higher risk of neonatal and postneonatal mortality when compared with their full-term peers. There was insufficient evidence to show that gestational length was independently associated with mortality beyond 1 year of age. Neonatal and postneonatal mortality improved with each decade of the study period.

Antenatal Corticosteroid Prophylaxis in Singleton and Multiple Pregnancies

BACKGROUND

The effects of antenatal corticosteroids (ANS) in multiple pregnancies are disputed. In this article, we examined whether estimated effects differ in singletons and multiples and in small for gestational age (SGA) preterm infants.

METHODS

We studied 17 073 singletons (81% treated with ANS) and 8274 multiples (86% treated) born at 24-33 weeks from the Italian Neonatal Network (2005-2013). We used Poisson regression models with robust variance to estimate adjusted risk ratios (RR) of in-hospital death, severe intraventricular haemorrhage (IVH), periventricular leukomalacia (PVL), and the composite outcome of severe IVH and death.

RESULTS

Mortality was lower among ANS-treated vs. ANS-untreated infants, both in singletons (RR 0.63, 95% confidence interval (CI) 0.58, 0.68) and in multiples (RR 0.85, 95% CI 0.73, 0.98). IVH and the composite outcome of IVH and death, but not PVL, also occurred less frequently among ANS-treated infants. For these outcomes, the effect of ANS was stronger in singletons than in multiples (+35%, +32%, and +22% for death, IVH, and the composite outcome, respectively). Also among SGA infants, singletons, and multiples, ANS-treated infants had lower risk of death, IVH and of composite outcome than untreated ones.

CONCLUSIONS

In this large cohort of preterm infants, both multiples and singletons treated with ANS had a lower risk of mortality, of severe IVH, and of composite outcome of IVH and death, both in the overall sample and in SGA infants. Although ANS effect was weaker in multiples, our results support current recommendations to administer ANS prophylaxis in multiple pregnancies at risk of preterm delivery.

European Consensus Guidelines on the Management of Respiratory Distress Syndrome - 2016 Update

Advances in the management of respiratory distress syndrome (RDS) ensure that clinicians must continue to revise current practice. We report the third update of the European Guidelines for the Management of RDS by a European panel of expert neonatologists including input from an expert perinatal obstetrician based on available literature up to the beginning of 2016. Optimizing the outcome for babies with RDS includes consideration of when to use antenatal steroids, and good obstetric practice includes methods of predicting the risk of preterm delivery and also consideration of whether transfer to a perinatal centre is necessary and safe. Methods for optimal delivery room management have become more evidence based, and protocols for lung protection, including initiation of continuous positive airway pressure and titration of oxygen, should be implemented from soon after birth. Surfactant replacement therapy is a crucial part of the management of RDS, and newer protocols for surfactant administration are aimed at avoiding exposure to mechanical ventilation, and there is more evidence of differences among various surfactants in clinical use. Newer methods of maintaining babies on non-invasive respiratory support have been developed and offer potential for greater comfort and less chronic lung disease. As technology for delivering mechanical ventilation improves, the risk of causing lung injury should decrease although minimizing the time spent on mechanical ventilation using caffeine and if necessary postnatal steroids are also important considerations. Protocols for optimizing the general care of infants with RDS are also essential with good temperature control, careful fluid and nutritional management, maintenance of perfusion and judicious use of antibiotics all being important determinants of best outcome.