Morbidity and mortality of very low birth weight multiples compared with singletons

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.

Comparison of neonatal outcomes between multiples and singletons among very low birth weight infants: the Korean Neonatal Network cohort study

OBJECTIVE

To compare neonatal outcomes between multiples and singletons among very low birth weight infants, this was a prospective cohort study that was conducted by collecting data registered in the Korean Neonatal Network database.

METHODS

From January 2013 to December 2016, there were 8265 infants in the Korean Neonatal Network database, and 2958 of them were from multiples. Among them, 2636 infants were twins, 308 infants were triplets, and 14 infants were quadruplets. Maternal and neonatal variables including and mortality major morbidity were compared. Finally, the predicted rates of major morbidity between singletons and multiples.

RESULTS

Multiples had higher gestational age, birth weight, Apgar score at 5 min, rates of cesarean section and artificial reproductive technology but lower maternal hypertension, oligohydramnios, chorioamnionitis rates and Clinical Risk Index for Babies scores II without base excess than the singletons. In univariate analysis, multiples had a lower incidence of respiratory distress syndrome, bronchopulmonary dysplasia, and sepsis. The mortality rate was not significantly different for overall gestational ages except for those born at ≤26 weeks of gestation. In multivariate logistic analysis, the incidences of intraventricular hemorrhage (grade ≥3), and retinopathy of prematurity requiring treatment were significantly higher than the singletons.

CONCLUSIONS

Mortality was not significantly different between multiples and singletons according to overall gestational age, except for multiples born at ≤26 weeks. A significant higher risk of intraventricular hemorrhage and retinopathy of prematurity requiring treatment was found in multiples. A new strategy to improve the mortality of immature multiples born at ≤26 weeks of gestation should be developed.

To be born twin: effects on long-term neurodevelopment of very preterm infants-a cohort study

Objective

To examine the effect of twin birth on long-term neurodevelopmental outcomes in a cohort of Italian preterm infants with very low birth weight.

Study design

We performed a retrospective cohort study on children born in a tertiary care centre. We included children born between 1 January 2007 and 31 December 2013 with a gestational age (GA) of ≤32 weeks and birth weight of <1,500 g. The infants born from twin pregnancies complicated by twin-to-twin transfusion syndrome and from higher-order multiple pregnancies were excluded. The children were evaluated both at 2 years corrected age and 5 years chronological age with Griffiths mental development scales revised (GMDS-R). The linear mixed effects models were used to study the effect of being a twin vs. being a singleton on GMDS-R scores, adjusting for GA, being born small for gestational age, sex, length of NICU stay, socio-economic status, and comorbidity score (CS) calculated as the sum of the weights associated with each of the major morbidities of the infants.

Results

A total of 301 children were included in the study, of which 189 (62.8%) were singletons and 112 (37.2%) were twins; 23 out of 112 twins were monochorionic (MC). No statistically significant differences were observed between twins and singletons in terms of mean general quotient and subscales at both 2 and 5 years. No effect of chorionicity was found when comparing scores of MC and dichorionic twins vs. singletons; however, after adjusting for the CS, the MC twins showed lower scores in the hearing and language and performance subscales at 5 years.

Conclusion

Overall, in our cohort of children born very preterm, twin infants were not at higher risk of neurodevelopmental impairment compared with singletons at pre-school age.

The Trace Element Concentrations and Oxidative Stress Parameters in Afterbirths from Women with Multiple Pregnancies

The aim of this study was to evaluate the intensity of oxidative stress by measuring the concentrations of lipid peroxidation products (LPO) in fetal membrane, umbilical cord, and placenta samples obtained from women with multiple pregnancies. Additionally, the effectiveness of protection against oxidative stress was assessed by measuring the activity of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), and glutathione reductase (GR). Due to the role of iron (Fe), copper (Cu), and zinc (Zn) as cofactors for antioxidant enzymes, the concentrations of these elements were also analyzed in the studied afterbirths. The obtained data were compared with newborn parameters, selected environmental factors, and the health status of women during pregnancy to determine the relationship between oxidative stress and the health of women and their offspring during pregnancy. The study involved women (n = 22) with multiple pregnancies and their newborns (n = 45). The Fe, Zn, and Cu levels in the placenta, umbilical cord, and fetal membrane were determined using inductively coupled plasma atomic emission spectroscopy (ICP-OES) using an ICAP 7400 Duo system. Commercial assays were used to determine SOD, GPx, GR, CAT, and LPO activity levels. The determinations were made spectrophotometrically. The present study also investigated the relationships between trace element concentrations in fetal membrane, placenta, and umbilical cord samples and various maternal and infant parameters in women. Notably, a strong positive correlation was observed between Cu and Zn concentrations in the fetal membrane (p = 0.66) and between Zn and Fe concentrations in the placenta (p = 0.61). The fetal membrane Zn concentration exhibited a negative correlation with shoulder width (p = -0.35), while the placenta Cu concentration was positively correlated with placenta weight (p = 0.46) and shoulder width (p = 0.36). The umbilical cord Cu level was positively correlated with head circumference (p = 0.36) and birth weight (p = 0.35), while the placenta Fe concentration was positively correlated with placenta weight (p = 0.33). Furthermore, correlations were determined between the parameters of antioxidative stress (GPx, GR, CAT, SOD) and oxidative stress (LPO) and the parameters of infants and maternal characteristics. A negative correlation was observed between Fe and LPO product concentrations in the fetal membrane (p = -0.50) and placenta (p = -0.58), while the Cu concentration positively correlated with SOD activity in the umbilical cord (p = 0.55). Given that multiple pregnancies are associated with various complications, such as preterm birth, gestational hypertension, gestational diabetes, and placental and umbilical cord abnormalities, research in this area is crucial for preventing obstetric failures. Our results could serve as comparative data for future studies. However, we advise caution when interpreting our results, despite achieving statistical significance.

Perinatal characteristics and neonatal outcomes of singletons and twins in Chinese very preterm infants: a cohort study

BACKGROUND

The prevalence of preterm birth has been rising, and there is a paucity of nationwide data on the perinatal characteristics and neonatal outcomes of twin deliveries of very preterm infants (VPIs) in China. This study compared the perinatal characteristics and outcomes of singletons and twins admitted to neonatal intensive care units (NICUs) in China.

METHODS

The study population comprised all infants born before 32 weeks in the Chinese Neonatal Network (CHNN) between January 2019 and December 2019. Three-level and population-average generalized estimating equation (GEE)/alternating logistic regression (ALR) models were used to determine the association of twins with neonatal morbidities and the use of NICU resources.

RESULTS

During the study period, there were 6634 (71.2%) singletons and 2680 (28.8%) twins, with mean birth weights of 1333.70 g and 1294.63 g, respectively. Twins were significantly more likely to be delivered by caesarean section (p < 0.01), have antenatal steroid usage (p = 0.048), have been conceived by assisted reproductive technology (ART) (p < 0.01), have a higher prevalence of maternal diabetes (p < 0.01) and be inborn (p < 0.01) than singletons. In addition, twins had a lower prevalence of small for gestational age, maternal hypertension, and primigravida mothers than singletons (all p < 0.01). After adjusting for potential confounders, twins had higher mortality rates (adjusted odds ratio [AOR] 1.28, 95% confidence interval [CI] 1.10-1.49), higher incidences of short-term composite outcomes (AOR 1.28, 95% CI 1.09-1.50), respiratory distress syndrome (RDS) (AOR 1.30, 95% CI 1.12-1.50), and bronchopulmonary dysplasia (BPD) (AOR 1.10, 95% CI 1.01-1.21), more surfactant usage (AOR 1.22, 95% CI 1.05-1.41) and prolonged hospital stays (adjusted mean ratio 1.03, 95% CI 1.00-1.06), compared to singletons.

CONCLUSION

Our work suggests that twins have a greater risk of mortality, a higher incidence of RDS and BPD, more surfactant usage, and longer NICU stays than singletons among VPIs in China.

Determinants of very low birth weight in India: The National Family Health Survey – 4

Background

Low birth weight (LBW) is susceptible to neonatal complications, chronic medical conditions, and neurodevelopmental disabilities. We aim to describe the determinants of very low birth weight (VLBW) in India and compare it with the determinants of LBW based on the National Family Health Survey – 4 (NHFS-4)

Methods

Data from the NFHS-4 on birthweight and other socio-demographic characteristics for the youngest child born in the family during the five years preceding the survey were used. Data of 147,762 infant–mother pairs were included. Multiple logistic regression models were employed to delineate the independent predictors of VLBW (birth weight<1500 g) or LBW  (birth weight: 1500-2499 g).

Results

Of the 147,762 children included in the study, VLBW and LBW were observed in 1.2% and 15.8% of children, respectively. The odds of VLBW were higher in female children (aOR: 1.36, 95% CI: 1.15–1.60), among mothers aged 13–19 years (aOR: 1.58, 95% CI: 1.22–2.07), mothers with severe or moderate anaemia (aOR: 1.61, 95% CI: 1.34–1.94), mothers without recommended antenatal care (aOR: 1.47, 95% CI: 1.31–1.90), maternal height less than 150 cm (aOR: 1.54, 95% CI: 1.29–1.85) and among mothers with multiple pregnancy (aOR: 21.34, 95% CI: 14.70–30.96) in comparison to their corresponding counterparts. In addition to the variables associated with VLBW, educational status of mothers (no education; aOR: 1.08, 95% CI: 1.02–1.15 and primary education; aOR: 1.16, 95% CI: 1.08–1.25), caste of the children (scheduled tribe; aOR: 1.13, 95% CI: 1.03–1.24), and wealthiness of the family (poorest wealth quintiles; aOR: 1.11, 95% CI: 1.03–1.19) were associated with LBW.

Conclusions

Interventions targeting improvements in antenatal care access, maternal health, and nutritional status may reduce the number of VLBW infants. Social determinants of LBW require further detailed study to understand the high propensity of low birth-weight phenotypes in the disadvantaged communities in India.

Determinants of very low birth weight in India: The National Family Health Survey – 4

Background Low birth weight (LBW) is susceptible to neonatal complications, chronic medical conditions, and neurodevelopmental disabilities. We aim to describe the determinants of very low birth weight (VLBW) in India based on the National Family Health Survey – 4 (NHFS-4). Methods Data from the NFHS 4 on birthweight and other socio-demographic characteristics for the youngest child born in the family during the five years preceding the survey were used. Data of 147,762 infant–mother pairs were included. Multiple logistic regression models were employed to delineate the independent predictors of VLBW (birth weight<1500 g) or LBW (birth weight <2500 g). Results Of the 147,762 children included in the study, VLBW and LBW were observed in 1.2% and 15.8% of children, respectively. The odds of VLBW were higher in female children (aOR: 1.36, 95% CI: 1.15–1.60), among mothers aged 13–19 years (aOR: 1.58, 95% CI: 1.22–2.07), mothers with severe or moderate anaemia (aOR: 1.61, 95% CI: 1.34–1.94), mothers without recommended antenatal care (aOR: 1.47, 95% CI: 1.31–1.90), maternal height less than 150 cm (aOR: 1.54, 95% CI: 1.29–1.85) and among mothers with multiple pregnancy (aOR: 21.34, 95% CI: 14.70–30.96) in comparison to their corresponding counterparts. In addition to the variables associated with VLBW, educational status of mothers (no education; aOR: 1.08, 95% CI: 1.02–1.15 and primary education; aOR: 1.16, 95% CI: 1.08–1.25), caste of the children (scheduled tribe; aOR: 1.13, 95% CI: 1.03–1.24), and wealthiness of the family (poorest wealth quintiles; aOR: 1.11, 95% CI: 1.03–1.19) were associated with LBW. Conclusions Interventions targeting improvements in antenatal care access, maternal health, and nutritional status may reduce the number of VLBW infants. Social determinants of LBW require further detailed study to understand the high propensity of low birth-weight phenotypes in the disadvantaged communities in India.

Feeding Twins with Human Milk and Factors Associated with Its Duration: A Qualitative and Quantitative Study in Southern Italy

BACKGROUND

Over the past year, there has been a rise in twin births. The current scientific consensus recommended breast-feed milk for all newborns for at least 6 months. They stated that it is possible to meet the nutritional needs of two or more newborns with only one mother's milk. More information would be desirable about the factors that influence or lead to the initiation and interruption of breastfeeding. The quality of the evidence available from multiple studies has been inconclusive and therefore led to controversial interpretations and practices.

AIMS

The first aim of this study was to analyze the extent of the feeding of multiples with breast milk in the experience of our clinical unit in terms of incidence and duration. The second objective was to evaluate the correlation between maternal, perinatal and neonatal variables with breast milk feeding rates and duration.

METHODS

The study was conducted between 2015 and 2020, in a NICU in Southern Italy (San Giovanni Rotondo, Foggia). Sixty-one women who have given birth to multiples were enrolled into the study. Newborn data were retrospectively collected by informatic database and breastfeeding information were collected by a questionnaire.

RESULTS

In our centre, the percentage of twins out of the total number of births over the years has almost doubled from 1.28% in 2015 to 2.48% in 2020 and the 88% of twins are premature. 18.1% received breast milk for more than 6 months and 6.3% received it for more than 12 months. Infants of lower gestational age and weight, born to multiparous, more mature and medium-high schooling mothers received breast milk for a longer period. 35% of women explained that the interruption of breastfeeding was due to the insufficient milk production and 41% to the stress and difficulties in managing the twins. Qualitative analysis of maternal narrative revealed, for many of them, the awareness of the importance of breastfeeding and the efforts made to try to give breast milk, but also fears about the quantity of milk and satiety of their children.

CONCLUSIONS

It is important to identify the factors both favoring and obstructing maternal milk feeding of multiples and it would be desirable the activation of a network of training and support for mothers after discharge, with particular regard to the categories found to be less inclined.

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.

Neurodevelopmental Outcome and Adaptive Behavior in Preterm Multiples and Singletons at 1 and 2 Years of Corrected Age

Background

Recent literature has investigated the role of multiple birth on neurodevelopmental outcomes of premature infants, especially extremely preterm ones. Multiple gestations are often associated to increased neurodevelopmental disability. Actually, research findings are controversial.

Objective

To compare the neurodevelopmental and behavioral outcomes of multiples and singletons in a cohort of preterm infants ≤28 weeks gestational age at 1 and 2 years of corrected age.

Methods

The study included 86 infants, born from January 2014 to September 2017 and enrolled in the follow-up program provided at authors’ Institution. Exclusion criteria included: major brain lesions and malformations, severe neuro-sensorial deficits, genetic syndromes, single-twin survivors. Thirty four multiples were compared to 52 singletons, using the Griffiths Mental Development Scales and the Child Behavior Checklist 1½–5. Statistical analysis was based on ANOVA techniques to test group differences. A p < 0.05 was considered statistically significant.

Results

The neurodevelopmental outcomes of multiples and singletons at 1 and 2 years of corrected age did not significantly differ at a general level (p > 0.05). Multiples showed significantly lower mean scores than singletons at 1 year in Locomotor (87.15 ± 11.94 vs. 92.48 ± 11.59) and Personal-Social (84.88 ± 10.25 vs. 89.63 ± 8.19) subscales. Considering the behavioral outcomes, higher rates of externalizing problems were observed in multiples at 2 years (54.27 ± 9.64 vs. 49.31 ± 10.39).

Conclusion

The slightly lower neurodevelopmental outcome showed by multiples, especially in the gross-motor and personal-social domains at 1 year, might be related to the specific environmental condition they experience. Multiple birth may affect mother’s sensitivity to infant’s needs and infant’s acquisition of emotional and behavioral regulation. This affects the separation process and the acquisition of the independent walking and other gross-motor skills. Being multiples might also induce an hyperstimulation and this could explain their higher vulnerability to externalizing problems (impulsiveness, hyperactivity, attention deficits). Additionally, males are more affected by the multiple condition than females.

Breastfeeding Disparities between Multiples and Singletons by NICU Discharge

Multiple pregnancy increases the risk of a range of adverse perinatal outcomes, including breastfeeding failure. However, studies on predictive factors of breastfeeding duration in preterm twin infants have a conflicting result. The purpose of this observational study was to compare feeding practices, at hospital discharge, of twin and singleton very low birth weight infants. The study is part of a prospective survey of a national Spanish cohort of very low birth weight infants (SEN1500) that includes 62 neonatal units. The study population comprised all infants registered in the network from 2002 to 2013. They were grouped into singletons and multiples. The explanatory variables were first analyzed using univariate models; subsequently, significant variables were analyzed simultaneously in a multiple stepwise backward model. During the twelve-year period, 32,770 very low birth weight infants were included in the database, of which 26.957 were discharged alive and included in this analysis. Nine thousand seven hundred and fifty-eight neonates were multiples, and 17,199 were singletons. At discharge, 31% of singleton infants were being exclusively breastfed, 43% were bottle-fed, and 26% were fed a combination of both. In comparison, at discharge, only 24% of multiple infants were exclusively breastfed, 43% were bottle-fed, and 33% were fed a combination of both (p < 0.001). On multivariable analysis, twin pregnancy had a statistically significant, but small effect, on cessation of breastfeeding before discharge (OR 1.10; 95% CI: 1.02, 1.19). Risks of early in-hospital breastfeeding cessation were also independently associated with multiple mother-infant stress factors, such as sepsis, intraventricular hemorrhage, retinopathy, necrotizing enterocolitis, intubation, and use of inotropes. Instead, antibiotic treatment at delivery, In vitro fertilization and prenatal steroids were associated with a decreased risk for shorter in-hospital breastfeeding duration. Multiple pregnancy, even in the absence of pathological conditions associated to very low birth weight twin infants, may be an impeding factor for in-hospital breastfeeding.