UNASSIGNED: Preterm birth and fetal growth restriction are the main determinants of perinatal mortality. In the absence of therapeutic interventions, management is restricted to the observation of fetal growth and fetoplacental perfusion to determine the timing of delivery. Fetal circulatory redistribution, known as \"brain sparing,\" represents a sign of fetal hypoxia and has been implemented in algorithms for when to deliver. In the absence of any other option, the nitric oxide donor pentaerythrityl tetranitrate (PETN), which has been shown to improve fetoplacental flow and reduce preterm birth in high-risk patients, is offered to patients as a personal therapy attempt. The aim of this study was to evaluate determinants related to pregnancy, including PETN intake during pregnancy, on immediate neonatal outcomes in a cohort of growth-restricted infants born before 32 completed weeks of gestation.
UNASSIGNED: We performed a retrospective cohort study of 98 infants born with a birth weight below the 10th percentile before 32 completed weeks of gestation at our tertiary care center between 2010 and 2019. PETN was offered to all mothers with a history of severe adverse pregnancy outcomes who were at high risk of developing fetal growth restriction as an individual therapy attempt.
UNASSIGNED: The mean gestational age at birth was 188.5 days, and the mean birth weight was 549 g, corresponding to a median percentile of three. In 73 (79.3%) cases, brain sparing occurred during pregnancy. A total of 22 (22.4%) neonates were stillborn, 20 died postnatally, and 37.3% developed a severe complication. Multivariable analysis revealed birth weight percentile, gestational age at birth, and gestational age when brain sparing first occurred to be robust predictors of mortality or severe neonatal morbidity. In 39 neonates of mothers taking PETN, this impact of brain sparing was not observed.
UNASSIGNED: Our study is the first to demonstrate a significant association between the early occurrence of brain-sparing and severe neonatal outcomes in a cohort of very early preterm, growth-restricted newborns. The data suggest that PETN intake may ameliorate the effect of brain sparing in the affected neonates.

BACKGROUND: Processing speed is a foundational skill supporting intelligence and executive function, areas often delayed in preterm-born children. The impact of early-life nutrition on gray matter facilitating processing speed for this vulnerable population is unknown.
METHODS: Magnetic resonance imaging and the Wechsler Preschool and Primary Scale of Intelligence-IV Processing Speed Index were acquired in forty 5-year-old children born preterm with very low birth weight. Macronutrient (grams per kilogram per day) and mother\'s milk (percentage of feeds) intakes were prospectively collected in the first postnatal month and associations between early-life nutrition and the primary outcome of brain regions supporting processing speed were investigated.
RESULTS: Children had a mean (SD) gestational age of 27.8 (1.8) weeks and 45% were male. Macronutrient intakes were unrelated, but mother\'s milk was positively related, to greater volumes in brain regions, including total cortical gray matter, cingulate gyri, and occipital gyri.
CONCLUSIONS: First postnatal month macronutrient intakes showed no association, but mother\'s milk was positively associated, with volumetric measures of total and regional cortical gray matter related to processing speed in preterm-born children. This exploratory analysis suggests early-life mother\'s milk supports processing speed by impacting structural underpinnings. Further research is needed on this potential strategy to improve preterm outcomes.

BACKGROUND: Adverse intrauterine environment was believed to have deleterious effects on the gonadal function. However, the association between impaired intrauterine growth and fertility in adult males has not been established.
OBJECTIVE: To compare the reproductive rates of males born small for gestational age (SGA), with low birth weight (LBW) or very low birth weight (VLBW) with control groups.
METHODS: The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement was followed to search PubMed, Web of Science, Cochrane Library, and Embase databases from inception to June 16, 2023. Cohort studies investigating the reproductive rates of males born SGA, with LBW or VLBW were included. A random or fixed effects model was used for different exposures.
RESULTS: A total of 10 studies out of 3,801 records were included. Males born SGA showed a higher risk of infertility than the control group (odds ratio, OR = 0.91, 95% confidence interval, 95% CI 0.89-0.93, p = 0.000). The reproductive rates of individuals born with LBW or VLBW were lower than the control group (OR = 0.86, 95% CI 0.78-0.94, p = 0.001; OR = 0.57, 95% CI 0.40-0.81, p = 0.002, respectively). Participants were further divided into two age groups of 18-35 and 35-45 years. In both subgroups, the reproductive rates were lower in males born SGA, with LBW or VLBW compared with controls. Sensitivity analysis showed the robustness of the pooled estimates among LBW and VLBW.
CONCLUSIONS: In summary, SGA, LBW, and VLBW were associated with a higher risk of male infertility in both early and middle adulthood. Achieving optimal intrauterine growth would be helpful to prevent male infertility.

BACKGROUND: Preterm birth is the leading cause of mortality in newborns, with very-low-birth-weight infants usually experiencing several complications. Breast milk is considered the gold standard of nutrition, especially for preterm infants with delayed gut colonization, because it contains beneficial microorganisms, such as Lactobacilli and Bifidobacteria.
OBJECTIVE: To analyze the gut microbiota of breastfed preterm infants with a birth weight of 1500 g or less.
METHODS: An observational study was performed on preterm infants with up to 36.6 wk of gestation and a birth weight of 1500 g or less, born at the University Hospital Dr. José Eleuterio González at Monterrey, Mexico. A total of 40 preterm neonates were classified into breast milk feeding (BM) and mixed feeding (MF) groups (21 in the BM group and 19 in the MF group), from October 2017 to June 2019. Fecal samples were collected before they were introduced to any feeding type. After full enteral feeding was achieved, the composition of the gut microbiota was analyzed using 16S rRNA gene sequencing. Numerical variables were compared using Student\'s t-test or using the Mann-Whitney U test for nonparametric variables. Dominance, evenness, equitability, Margalef\'s index, Fisher\'s alpha, Chao-1 index, and Shannon\'s diversity index were also calculated.
RESULTS: No significant differences were observed at the genus level between the groups. Class comparison indicated higher counts of Alphaproteobacteria and Betaproteobacteria in the initial compared to the final sample of the BM group (P < 0.011). In addition, higher counts of Gammaproteobacteria were detected in the final than in the initial sample (P = 0.040). According to the Margalef index, Fisher\'s alpha, and Chao-1 index, a decrease in species richness from the initial to the final sample, regardless of the feeding type, was observed (P < 0.050). The four predominant phyla were Bacteroidetes, Actinobacteria, Firmicutes, and Proteobacteria, with Proteobacteria being the most abundant. However, no significant differences were observed between the initial and final samples at the phylum level.
CONCLUSIONS: Breastfeeding is associated with a decrease in Alphaproteobacteria and Betaproteobacteria and an increase of Gammaproteobacteria, contributing to the literature of the gut microbiota structure of very low-birth-weight, preterm.

OBJECTIVE: To study the association between Ureaplasma colonization and bronchopulmonary dysplasia (BPD) with different definitions in very low birth weight (VLBW) infants.
METHODS: A retrospective cohort study was performed with VLBW infants admitted from January 2019 to October 2021. Neonates with a positive respiratory tract Ureaplasma culture were included in the study group. Control group infants, matched for gestational age (±1 week), birth weight (±100 g), and birth year, had a negative respiratory tract Ureaplasma culture during the same period. The primary outcomes included the incidence and severity of BPD, defined by various criteria.
RESULTS: The study included 302 neonates (151 in the study group and 151 in the control group). After adjusting for confounders, Ureaplasma colonization was not associated with BPD as defined by the National Institutes of Health (NIH) in 2001 (adjusted odds ratio [aOR]: 0.820, 95% confidence interval [CI]: 0.362-1.860, p = .635). However, it was associated with BPD as defined by the NIH in 2018 (aOR: 2.490, 95% CI: 1.128-5.497, p = .024) and the Neonatal Research Network (NRN) in 2019 (aOR: 2.352, 95% CI: 1.077-5.134, p = .032). Additionally, VLBW infants with Ureaplasma colonization had a higher risk of moderate-severe BPD according to the NIH 2001 (aOR: 2.352, 95% CI: 1.077-5.134, p = .032), NIH 2018 (aOR: 6.339, 95% CI: 1.686-23.836, p = .006), and NRN 2019 definitions (aOR: 3.542, 95% CI: 1.267-9.904, p = .016).
CONCLUSIONS: Ureaplasma colonization is not associated with BPD by the NIH 2001 definition, but is associated with an increased incidence by the NIH 2018 or NRN 2019 definitions.

UNASSIGNED: Scientific evidence provides a widened view of differences in immune response between male and female neonates. The X-chromosome codes for several genes important in the innate immune response and neonatal innate immune cells express receptors for, and are inhibited by, maternal sex hormones. We hypothesized that sex differences in innate immune responses may be present in the neonatal population which may contribute to the increased susceptibility of premature males to sepsis. We aimed to examine the in vitro effect of pro-inflammatory stimuli and hormones in neutrophils and monocytes of male and female neonates, to examine the expression of X-linked genes involved in innate immunity and the miRNA profiles in these populations.
UNASSIGNED: Preterm infants (n = 21) and term control (n = 19) infants were recruited from the Coombe Women and Infants University Hospital Dublin with ethical approval and explicit consent. The preterm neonates (eight female, 13 male) were recruited with a mean gestation at birth (mean ± SD) of 28 ± 2 weeks and corrected gestation at the time of sampling was 30 + 2.6 weeks. The mean birth weight of preterm neonates was 1084 ± 246 g. Peripheral blood samples were used to analyze immune cell phenotypes, miRNA human panel, and RNA profiles for inflammasome and inflammatory genes.
UNASSIGNED: Dividing neutrophil results by sex showed no differences in baseline CD11b between sexes among either term or preterm neonates. Examining monocyte CD11b by sex shows, that at baseline, total and classical monocytes have higher CD11b in preterm females than preterm males. Neutrophil TLR2 did not differ between sexes at baseline or following lipopolysaccharide (LPS) exposure. CD11b expression was higher in preterm male non-classical monocytes following Pam3CSK treatment when compared to females, a finding which is unique to our study. Preterm neonates had higher TLR2 expression at baseline in total monocytes, classical monocytes and non-classical monocytes than term. A sex difference was evident between preterm females and term females in TLR2 expression only. Hormone treatment showed no sex differences and there was no detectable difference between males and females in X-linked gene expression. Two miRNAs, miR-212-3p and miR-218-2-3p had significantly higher expression in preterm female than preterm male neonates.
UNASSIGNED: This study examined immune cell phenotypes and x-linked gene expression in preterm neonates and stratified according to gender. Our findings suggest that the responses of females mature with advancing gestation, whereas male term and preterm neonates have very similar responses. Female preterm neonates have improved monocyte activation than males, which likely reflects improved innate immune function as reflected clinically by their lower risk of sepsis. Dividing results by sex showed changes in preterm and term infants at baseline and following LPS stimulation, a difference which is reflected clinically by infection susceptibility. The sex difference noted is novel and may be limited to the preterm or early neonatal population as TLR2 expression on monocytes of older children does not differ between males and females. The differences shown in female and male innate immune cells likely reflect a superior innate immune defense system in females with sex differences in immune cell maturation. Existing human studies on sex differences in miRNA expression do not include preterm patients, and most frequently use either adult blood or cord blood. Our findings suggest that miRNA profiles are similar in neonates of opposite sexes at term but require further investigation in the preterm population. Our findings, while novel, provide only very limited insights into sex differences in infection susceptibility in the preterm population leaving many areas that require further study. These represent important areas for ongoing clinical and laboratory study and our findings represent an important contribution to exiting literature.

BACKGROUND: Patent ductus arteriosus (PDA) is commonly encountered morbidity which often occurs as up to 60% of extremely preterm infants born at < 29 weeks gestational age (GA).
OBJECTIVE: This study aims to assess the clinical risk factors associated with PDA ligation among very low birth weight infants (VLBWI) and evaluate the neurodevelopmental outcomes of those who underwent PDA ligation.
METHODS: A total of 540 VLBWI were initially diagnosed with PDA in our 50-bed level IV NICU at Seoul St. Mary\'s Hospital, The Catholic University of Korea, between January 2015 and June 2023. Among these 540 VLBWI with PDA, only 221 had consistent hemodynamically significant (hs) PDA which required intervention including fluid restriction, medical treatment, or surgical ligation. In this study, only those 221 VLBWI with hsPDA who underwent neurodevelopmental assessment at corrected 18-24 months of age were included in this study analysis.
RESULTS: Out of 221 VLBWI diagnosed with hemodynamically significant (hs) PDA, 133 (60.2%) underwent PDA ligation, while the remaining 88 (39.8%) had their hs PDAs closed either medically or with fluid restriction. The mean gestational age and birth weight were significantly lower in PDA ligation group compared to no PDA ligation group (27.02 ± 2.17 vs. 27.98 ± 2.36, 907.31 ± 258.36 vs. 1006.07 ± 283.65, p = 0.001, 0.008). Resuscitation including intubation at delivery and intraventricular hemorrhage (IVH) (grade ≥ 3) were significantly higher in PDA ligation group. The clinical outcomes in the PDA ligation group revealed significantly worse oucomes compared to the no PDA ligation group. Both resuscitation, including intubation at delivery, and IVH (grade ≥ 3), consistently exhibited an increased risk for PDA ligation in a multivariable logistic regression analysis. Concerning neurodevelopmental outcomes, infants who underwent PDA ligation demonstrated significantly lower cognitive scores. However, only IVH (grade ≥ 3) and PVL were consistently associated with an increased risk of abnormal neurodevelopment at the corrected age of 18-24 months.
CONCLUSIONS: In our study, despite the consistent association between cognitive developmental delays in VLBWI who underwent PDA ligation, we observed that sicker and more vulnerable VLBWIs, specifically those experincing severe IVH, consistently exhibited an increased risk for both PDA ligation and abnormal neurodevelopment at the corrected age of 18-24 months.

OBJECTIVE: Cerebral tissue oxygen saturation (SctO2) and cerebral fractional tissue oxygen extraction (cFTOE) changes with GA in preterm infants. This study examines changes in frequency, duration, and severity of SctO2 desaturation and increased cFTOE with GA.
METHODS: The lower limit of normal SctO2, the event threshold, was calculated using a tolerance interval method with 95% confidence interval (CI) and 90% probability. Cerebral desaturation events were defined as: 1) a drop below event threshold for at least 30 s (s), 2) preceded by a period above the event threshold for at least 30s, and 3) followed by a period above the threshold for at least 60s.
RESULTS: 86% of infants <28 wk experienced one or more SctO2 desaturation event compared to 57% in >28 wk, odds ratios (OR) 4.5 (CI:1.3-15.3, p = 0.016). The severity of SctO2 desaturation events decreases at a rate of 77.9 units per wk increase in GA (p < 0.001). 39.3% of infants <28 wk experienced one or more increased cFTOE events compared to 28.6% in >28 wk, OR 1.6 (CI:0.6-4.4, p = 0.35). The severity of increasing cFTOE events decreased by 69.7 units per wk increase in GA (p < 0.001).
CONCLUSIONS: Cerebral tissue oxygen desaturation events decrease in frequency and severity with increasing GA. The severity of increased cFTOE episodes decrease with GA.

OBJECTIVE: To explore foveal and parafoveal thickness in adults born preterm with very low birth weight (VLBW) and its association with best-corrected visual acuity (BCVA) and gestational age (GA) compared to adults born at term.
METHODS: In a joint study of the Helsinki Study of Very Low Birth Weight Adults (Finland) and the NTNU Low Birth Weight Life study (Norway), 106 VLBW and 143 term-born controls were examined with spectral-domain optical coherence tomography and BCVA at age 31-43 years. Thickness of retinal layers was segmented in the foveal and parafoveal areas of the macula.
RESULTS: The total retinal thickness in the foveal area was thicker in VLBW adults compared with controls; mean (SD): 292.5 μm (28.2) and 272.4 μm (20.2); p < 0.001, and thinner in the parafoveal areas of the macula. These findings could be explained by a thicker inner retinal layer in the foveal area found in VLBW adults compared with controls (mean difference 20.4 μm; CI: 15.0 to 25.9), where a thicker fovea was associated with lower GA, but not BCVA.
CONCLUSIONS: Adults born preterm with VLBW had a thicker retina in the foveal area than controls and this was associated with GA, but not with BCVA. These changes seem to be related to a thicker inner retinal layer in VLBW adults. The findings imply that signs of macular underdevelopment are still present in adulthood, but not necessarily related to reduced visual function.

BACKGROUND: Time to full enteral feeding is the time when neonates start to receive all of their prescribed nutrition as milk feeds. Delayed to achieve full enteral feeding had resulted in short- and long-term physical and neurological sequelae. However, there are limited studies to assess the time to full enteral feeding and its predictors among very low birth-weight neonates in Ethiopia. Therefore, this study aimed to assess the time to full enteral feeding and its predictors among very low birth-weight neonates admitted to comprehensive specialized hospitals in Northwest Ethiopia.
METHODS: A multi-center institutional-based retrospective follow-up study was conducted among 409 VLBW neonates from March 1, 2019 to February 30, 2023. A simple random sampling method was used to select study participants. Data were entered into EpiData version 4.2 and then exported into STATA version 16 for analysis. The Kaplan-Meier survival curve together with the log-rank test was fitted to test for the presence of differences among groups. Proportional hazard assumptions were checked using a global test. Variables having a p- value < 0.25 in the bivariable Cox-proportional hazard model were candidates for multivariable analysis. An adjusted Hazard Ratio (AHR) with 95% Confidence Intervals (CI) was computed to report the strength of association, and variables having a P-value < 0.05 at the 95% confidence interval were considered statistically significant predictor variables.
RESULTS: The median time to full enteral feeding was 10 (CI: 10-11) days. Very Low Birth-Weight (VLBW) neonates who received a formula feeding (AHR: 0.71, 95% CI: 0.53, 0.96), gestational age of 32-37 weeks (AHR: 1.66, 95% CI: 1.23, 2.23), without Necrotizing Enterocolitis (NEC) (AHR: 2.16, 95% CI: 1.65, 2.84), and single birth outcome (AHR: 1.42, 95% CI: 1.07, 1.88) were statistically significant variables with time to full enteral feeding.
CONCLUSIONS: This study found that the median time to full enteral feeding was high. Type of feeding, Necrotizing Enterocolitis (NEC), Gestational Age (GA) at birth, and birth outcome were predictor variables. Special attention and follow-up are needed for those VLBW neonates with NEC, had a GA of less than 32 weeks, and had multiple birth outcomes.