Search Results (928)

Background: Late-onset neonatal sepsis (LONS) remains a major cause of morbidity in preterm neonates admitted to the neonatal intensive care unit (NICU), yet the contribution of vitamin D status to neonatal infectious susceptibility remains uncertain. Objective: To evaluate clinical and demographic variables and serum vitamin D levels assessed at birth in preterm neonates with and without LONS. Methods: A retrospective observational cohort study was conducted in a tertiary NICU in northeastern Mexico between May 2023 and October 2024. Preterm neonates (<37 weeks of gestation) with serum 25(OH)D measured within the first hour of life were included. Vitamin D status was classified as sufficient (≥30 ng/mL), insufficient (20–29 ng/mL), or deficient (<20 ng/mL). LONS was defined as sepsis occurring after 72 h of life. Comparisons between neonates with and without LONS were performed using Fisher’s exact test for categorical variables and Student’s t-test or Mann–Whitney U test for continuous variables, as appropriate. Results: Twenty-nine preterm neonates were included (mean gestational age: 32.0 ± 2.6 weeks; mean birth weight: 1748 ± 545 g). The mean serum 25(OH)D level at birth was 35.5 ± 13.0 ng/mL. LONS occurred in 31% (9/29) of neonates, of which 55% were microbiologically confirmed. No significant differences were observed in vitamin D levels between neonates with and without LONS (35.0 ± 12.0 vs. 35.7 ± 13.7 ng/mL; p = 0.899). Vitamin D deficiency was not associated with LONS (OR 1.13, 95% CI 0.09–14.28). The prevalence of vitamin D deficiency was low (10%) in this cohort. Conclusions: A clear association between serum 25(OH)D levels at birth and the development of LONS could not be demonstrated in this small exploratory cohort. Given the limited sample size and low prevalence of vitamin D deficiency, further multicenter prospective studies are required to better understand the potential relationship between vitamin D status and neonatal infectious outcomes. Full article

Background/Objectives: Accurate identification of neonatal malnutrition is essential for optimizing perinatal care and reducing adverse outcomes. Traditional birthweight-based methods fail to account for body proportionality, limiting their ability to distinguish constitutionally small or large neonates from those with true nutritional abnormalities. We previously developed a customized fetal body mass index (cFBMI) percentile model that incorporates both weight and length, adjusted for maternal and fetal characteristics. This study aims to perform a temporal external validation of the cFBMI model following the Riley et al. framework, comparing its performance against the GROW customized birthweight model and the INTERGROWTH-21st population-based standard. Methods: A temporal validation study was conducted using singleton deliveries from Hospital Universitario de Puerto Real, Cádiz, Spain. The development cohort comprised 7864 deliveries (2002–2021); the validation cohort comprised 4441 deliveries (2022–2025). Inclusion criteria: singleton pregnancy, gestational age of 33–42 + 6 weeks, birthweight of 500–6000 g, known neonatal sex and length, and complete maternal data. The Ponderal Index (PI = weight/length³ × 100) stratified by sex and gestational age served as the gold standard (undernutrition: PI < p10; overnutrition: PI > p90). Discrimination was assessed using the area under the receiver operating characteristic curve (AUC) with bootstrap 95% confidence intervals (2000 iterations) and DeLong tests. Calibration was evaluated by comparing observed versus expected proportions across percentile categories. Clinical utility was assessed using decision curve analysis (DCA). Temporal stability was quantified by comparing AUCs and Brier scores between the development and validation cohorts. Results: In the validation cohort (n = 4441), cFBMI demonstrated superior discrimination for both undernutrition (AUC: 0.962) and overnutrition (AUC: 0.961) compared with GROW (AUC: 0.751 and 0.676, respectively) and INTERGROWTH-21st (AUC: 0.756 and 0.682, respectively); all DeLong comparisons p < 0.0001. The cFBMI exhibited excellent temporal stability (ΔAUC = −0.004 for undernutrition, +0.002 for overnutrition) and superior calibration (observed proportions: 9.6%/81.7%/8.8% vs. expected 10%/80%/10%; χ² = 9.22, p = 0.010). The decision curve analysis confirmed the superior net benefit of cFBMI across all threshold probabilities. Conclusions: The customized fetal BMI percentile model demonstrates excellent and temporally stable discriminative performance in this single-institution temporal validation study, with superior calibration and apparent advantages in clinical utility as determined by decision curve analysis compared with existing methods. Its integration of body proportionality provides conceptual alignment with the Ponderal Index gold standard. These findings are promising but require confirmation through external multicenter validation before clinical implementation can be recommended. Although the mathematical relationship between the index test (weight/length²) and the reference standard (weight/length³) should be considered when interpreting the magnitude of discrimination metrics, validation against independent clinical outcomes is an essential next step. The cFBMI thus provides a proportionality-aware nutritional metric whose primary discriminative advantage over weight-based methods is realized at and beyond the moment of birth, and which is forward-compatible with emerging modalities for independent prenatal fetal length estimation. Full article

Bronchopulmonary dysplasia (BPD) remains a major complication of extreme prematurity, driven in part by persistent inflammation. Interleukin (IL)-1–mediated signaling plays a central role in sustaining lung injury, making IL-1 blockade a potential therapeutic target. Evidence on the use of anakinra, a recombinant IL-1 receptor antagonist, in neonatal BPD is still limited. We report the case of a female preterm infant (28⁺² weeks’ gestation, birth weight 800 g, −1.41 zs) affected by BPD requiring prolonged respiratory support. Due to persistent respiratory failure despite standard therapies, off-label treatment with subcutaneous anakinra (5 mg/kg twice daily) was initiated at 150 days of life. Clinical respiratory parameters and exploratory salivary inflammatory biomarkers (IL-6 and soluble urokinase plasminogen activator receptor, suPAR) were longitudinally monitored. Following anakinra initiation, the patient showed a gradual improvement in respiratory parameters, with reduction in oxygen requirement, mean airway pressure, and improved gas exchange. Respiratory support was gradually de-escalated from nasal intermittent positive pressure ventilation to continuous positive airway pressure and subsequently to high-flow nasal cannula. Salivary suPAR levels demonstrated a decreasing trend, while IL-6 showed transient fluctuations, partly associated with intercurrent infections. Treatment was generally well tolerated during the observation period. The infant was discharged on minimal respiratory support, with continued improvement during follow-up. This case suggests a possible role of IL-1 blockade in the modulation of persistent inflammation in BPD with a refractory clinical course, although the observed clinical course may also reflect the natural evolution of the disease. Longitudinal salivary biomarkers may represent a feasible, exploratory, non-invasive approach to describe inflammatory dynamics over time. Larger prospective studies are needed to evaluate the efficacy, safety, and optimal treatment protocols of anakinra. Full article

Tuberculosis remains one of the leading infectious causes of morbidity and mortality worldwide, disproportionately affecting women of reproductive age, particularly in low- and middle-income countries. Tuberculosis during pregnancy represents a major clinical challenge, as physiological and immunological changes associated with pregnancy may obscure symptoms, delay diagnosis, and contribute to adverse maternal and perinatal outcomes. This narrative review provides an updated and clinically oriented overview of tuberculosis during pregnancy, with particular emphasis on diagnostic challenges, imaging strategies, microbiological testing, maternal–fetal complications, and therapeutic management. Key topics include symptom-based screening, tuberculin skin test and interferon gamma release assays, as well as molecular diagnostic methods such as GeneXpert Mycobacterium tuberculosis/Rifampicin (MTB/RIF) and Xpert MTB/RIF Ultra, chest radiography, computed tomography, and emerging biomarkers. We also discuss the impact of tuberculosis on pregnancy outcomes, including prematurity, low birth weight, maternal morbidity, and neonatal complications, as well as the particular challenges posed by human immunodeficiency virus HIV coinfection and multidrug-resistant tuberculosis. Current treatment strategies, preventive approaches, postpartum care, neonatal management, and Bacille Calmette–Guérin vaccination are reviewed in light of contemporary evidence and international recommendations. Finally, we highlight practical diagnostic algorithms, current evidence gaps, and priorities for future research aimed at improving maternal and neonatal outcomes in both high- and low-resource settings. Full article

Background/Objectives: Children born very preterm (VP) are at increased risk of later emotional and cognitive difficulties, including anxiety symptoms during childhood. Altered early brain development, particularly within subcortical circuits involved in emotional regulation, may contribute to this vulnerability. This study aimed to assess anxiety symptoms in preschool-aged children born VP, examine their relationship with cognitive performance, and determine whether neonatal brain volumes at term-equivalent age (TEA) were associated with later anxiety symptoms. We also explored whether cognition mediated the association between neonatal striatal volumes and anxiety. Methods: We conducted a longitudinal cohort study of infants born at ≤32 weeks of gestation and/or with a birth weight ≤1500 g admitted to a tertiary neonatal intensive care unit between 2018 and 2021. At 4–6 years of age, anxiety symptoms were assessed using the Child Behavior Checklist (CBCL) Anxiety Problems subscale, and cognitive performance was evaluated with the Wechsler Preschool and Primary Scale of Intelligence-IV (WPPSI-IV). Neonatal magnetic resonance imaging performed at TEA was used to obtain regional brain volumetric measures. Associations were analyzed using adjusted linear regression, interaction-based volumetric modeling, path analysis, and receiver operating characteristic analysis. Results: Ninety-five children were included, and 24 (25.3%) showed clinically relevant anxiety symptoms according to the CBCL Anxiety Problems subscale. Higher WPPSI-IV scores were associated with lower anxiety scores (β = −0.183; p = 0.042). The best-fitting MRI model included caudate volume, putamen volume, and their interaction, with a significant association between the putamen–caudate interaction and anxiety symptoms (β = −17.807; p < 0.001). In the path model, both cognition and the putamen–caudate interaction were directly associated with anxiety, whereas the indirect effect through cognition was not significant. The final MRI model showed acceptable discrimination for clinically relevant anxiety (AUC = 0.796). Conclusions: Anxiety symptoms were frequent in preschool-aged children born VP and were associated with lower cognitive performance. Neonatal striatal volumetric organization, particularly the interaction between the putamen and caudate volumes, was independently associated with later anxiety symptoms, suggesting that cognitive and early neural factors may contribute to anxiety risk through parallel rather than mediated pathways. Full article

Electronic waste (e-waste) recycling releases heavy metals into surrounding environments, creating potential health risks for nearby populations, particularly pregnant women and developing fetuses. This systematic review evaluated human evidence linking prenatal exposure to heavy metals originating from informal e-waste recycling with adverse pregnancy and neonatal outcomes. Electronic databases, including PubMed and Scopus, were searched through 23 September 2025, for studies measuring heavy metal exposure among pregnant women or neonates living in e-waste–affected communities. Following the Navigation Guide methodology, eight observational studies met the inclusion criteria and were assessed for risk of bias and strength of evidence. Across studies, concentrations of heavy metals were higher in exposed populations and were detected in maternal blood, placenta, cord blood, urine, and meconium samples from exposed populations. Prenatal exposure was consistently associated with adverse outcomes, with many studies reporting statistically significant associations between heavy metal exposure and reduced birth weight, length, head circumference, gestational age, neonatal body mass index, lower Apgar scores, impaired neonatal neurobehavioral development, placental molecular alterations, endocrine disruption, and increased neonatal DNA damage. Overall, the evidence was rated as moderate quality with sufficient evidence linking prenatal heavy-metal exposure from e-waste to impaired fetal growth and neonatal development, and limited evidence for pregnancy complications. These findings highlight the need for improved regulation of e-waste recycling and strengthened public health protections for vulnerable populations. Full article

Backgroud and Objectives: To evaluate conventional Doppler indices and the novel middle cerebral artery (MCA) diastolic deceleration area (DDA) in pregnancies complicated by gestational diabetes mellitus (GDM), and to explore their associations with perinatal outcomes. Prospective case–control study conducted at a tertiary referral perinatology center. Materials and Methods: The study included 83 women with GDM and 92 healthy controls. Standard fetal biometric and Doppler parameters—umbilical artery, MCA, ductus venosus, cerebroplacental ratio, and umbilicocerebral ratio—were assessed, alongside calculation of MCA DDA. Perinatal outcomes were recorded. Results: Most conventional Doppler indices did not differ between groups, except for lower MCA dicrotic notch velocity and higher ductus venosus time-averaged maximum velocity in the GDM group. MCA DDA values did not differ significantly between GDM and control groups (6.67 [5.02–8.20] vs. 7.05 [5.21–8.39] cm·s, p = 0.444) and showed no difference between insulin- and diet-controlled subgroups (p > 0.05). MCA DDA showed significant correlations with gestational age, MCA peak systolic velocity, and birth weight. However, after adjustment for potential confounders, gestational age remained the only independent determinant of MCA DDA. The multivariable analysis evaluating composite adverse neonatal outcomes was limited by the small number of adverse events (n = 14). Conclusions: MCA DDA did not differ between GDM and control pregnancies and primarily reflected gestational age-related physiological variation rather than diabetes specific hemodynamic changes. However, its relationship with adverse neonatal outcomes remains uncertain and requires further investigation in larger prospective studies. Full article

Background and Objectives: To evaluate maternal characteristics associated with placenta previa in comparison with breech cesarean controls, as well as maternal and neonatal outcomes. Materials and Methods: A retrospective case–control study was conducted at the Hospital of Lithuanian University of Health Sciences, Kaunas Clinics (2015–2022). A total of 150 cases of placenta previa were compared with a control group of participants who underwent cesarean delivery due to fetal breech presentation without placenta previa. Results: In multivariable analysis, higher parity, prior cesarean delivery, in vitro fertilization, prior surgical termination of pregnancy, and prior uterine surgery were independently associated with placenta previa compared with breech cesarean controls. Maternal complications were significantly more frequent in the placenta previa group and included placenta accreta spectrum disorders, second- and third-trimester hemorrhage, postpartum hemorrhage, and increased need for blood transfusion. The most severe outcomes, including cesarean hysterectomy, occurred exclusively in cases complicated by placenta accreta spectrum disorders. Neonatal outcomes in the placenta previa group were characterized by higher rates of preterm birth, low Apgar scores, and birth weight < 2500 g. Adverse neonatal outcomes were partly associated with earlier gestational age at delivery. However, placenta previa remained associated with low Apgar score after adjustment. Conclusions: Compared with breech cesarean controls, placenta previa was associated with multiple maternal characteristics, including higher parity, prior cesarean delivery, in vitro fertilization, prior surgical termination of pregnancy, and prior uterine surgery. The condition is linked to increased maternal hemorrhagic morbidity, particularly in cases complicated by placenta accreta spectrum disorders, as well as adverse neonatal outcomes mainly related to prematurity. These findings highlight the importance of careful antenatal monitoring and delivery planning in specialized centers. Full article

Background/Objectives: Peripheral(-muscle) oxygenation assessed with near-infrared spectroscopy might serve as an early marker of infection/inflammation; however, evidence of its clinical relevance is lacking so far. This study aimed to develop a peripheral(-muscle) oxygenation and perfusion score (POP-Score) using the peripheral(-muscle) tissue oxygenation index (pTOI) combined with non-invasive monitoring parameters within six hours after birth. The POP-Score was designed to explore associations with elevated C-reactive protein (CRP), as an early infection/inflammation marker, in term and late-preterm neonates. Methods: Secondary outcome parameters from a prospective observational study were analysed. Included neonates weighed ≥2000 g with respiratory distress, excluding those with umbilical artery pH < 7.20. Neonates with CRP ≥ 20 mg/L were 1:4-matched to those with CRP < 20 mg/L by gestational age (±2 weeks). For pTOI measurements, a sensor was placed for a duration of 30 s, followed by four further reapplications of the sensor, using the NIRO200NX within the first six hours after birth. The POP-Score was established using the following formula: (pTOI [%] × subcutaneous fat layer thickness [cm] × heart rate [bpm])/(arterial oxygen saturation [%] × systolic blood pressure [mmHg]). POP-Score was correlated with the highest CRP within 48 h. Results: Thirty neonates were included (median gestational age: 39.1 weeks [CRP < 20 mg/L group] vs. 37.3 weeks [CRP ≥ 20 mg/L group], p = 0.299; median birth weight: 3561 g vs. 3260 g, p = 0.058, respectively). Median POP-Scores were significantly different: 1.11 (CRP ≥ 20 mg/L) vs. 0.85 (CRP < 20 mg/L), p < 0.001. POP-Score correlated positively with CRP (r = 0.341; p = 0.070). In this small exploratory cohort, a POP-Score cut-off of 1.00 was associated with CRP ≥ 20 mg/L (100% sensitivity and 87% specificity); however, these estimates are uncertain due to the limited sample size. Conclusions: This study is the first to describe a new score for peripheral(-muscle) oxygenation and perfusion (POP-Score), which may represent a potential approach for early, non-invasive assessment but requires validation in adequately powered studies before any clinical application. Trial Registration: Clinicaltrials.gov, Trial registration number: NCT04818762, Date of Registration: 26 March 2021. Full article

Background: Neonatal birth weight is a key determinant of short- and long-term health outcomes. Pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) are important predictors of birth weight; however, their independent associations remain unclear, particularly in settings where national GWG guidelines are lacking. Methods: A prospective cohort study was conducted among 340 pregnant women in Ulaanbaatar, Mongolia in 2022. Data were collected using standardized questionnaires and anthropometric measurements. Pre-pregnancy BMI and GWG were classified according to World Health Organization criteria and the 2009 Institute of Medicine guidelines. Multivariable linear regression models were used to examine independent associations with neonatal birth weight. Results: The mean maternal age, pre-pregnancy BMI, and GWG were 30.3 ± 6.0 years, 23.5 ± 4.4 kg/m², and 14.3 ± 6.2 kg, respectively. Both BMI and GWG were independently associated with neonatal birth weight (p < 0.001), with no significant interaction observed (p = 0.147). Birth weight increased by 29.7 g (95% CI: 18.6–40.8) per 1 kg/m² increase in BMI and by 31.7 g (95% CI: 24.0–39.4) per 1 kg increase in GWG. Compared with normal BMI, overweight/obesity was associated with higher birth weight, while excessive GWG increased and inadequate GWG decreased birth weight (all p < 0.05). Conclusions: Pre-pregnancy BMI and GWG were independently associated with neonatal birth weight, with GWG showing a slightly stronger association. These findings highlight the importance of optimizing maternal weight before and during pregnancy. Countries undergoing rapid nutritional transitions may benefit from developing context-specific GWG guidelines, with Mongolia representing a relevant example. Full article

Background/Objectives: Neonatal sepsis remains a major contributor to neonatal morbidity and mortality worldwide, yet diagnostic uncertainty and heterogeneous clinical presentation continue to challenge early recognition and management. Early-onset sepsis (EOS), typically arising within the first 72 h of life, is strongly influenced by maternal and perinatal factors. Limited data exist on the temporal evolution of clinical system involvement during the first week of life. This study aimed to identify the predominant clinical systems involved in preterm and term neonates with suspected or confirmed sepsis and to determine maternal and neonatal risk factors associated with early disease severity, persistent sepsis, and adverse outcomes. Methods: A total of 297 neonates met the inclusion criteria. Most infants (99.3%) were admitted before 72 h of life. Clinical system involvement was recorded daily, and maternal–neonatal risk factors were analyzed to identify predictors of advanced sepsis at presentation, persistent sepsis at Day 7, and mortality. Results: Respiratory involvement was the predominant clinical system affected on Day 1 (57.2%) and remained common through Day 3. CNS, gastrointestinal, and skin involvement were infrequent. Lower gestational age (p = 0.035) and prolonged rupture of membranes >18 h (p = 0.043) independently predicted sepsis at Day 1. Advanced sepsis at admission was associated with lower birth weight, lower gestational age, older maternal age, and absence of intrapartum antibiotics (all p ≤ 0.001). Persistent sepsis at Day 7 was linked to prematurity (p = 0.008), higher mortality (p < 0.001), and prolonged hospitalization (p = 0.001). Conclusions: Respiratory involvement was the most common clinical system affected in neonates with EOS. Prematurity, low birth weight, prolonged rupture of membranes, and maternal intrapartum infection significantly increased the risk of severe disease. Understanding the evolution of clinical system involvement during the first days of life may support more precise risk stratification and reduce unnecessary antibiotic exposure. Full article

β-thalassemia minor, often referred to as the β-thalassemia trait, is among the most prevalent hemoglobinopathies globally, impacting around 80–90 million carriers, with a prevalence of up to 15% among Mediterranean, Middle Eastern, and Asian populations. Although traditionally regarded as clinically benign, pregnancy imposes hematologic and metabolic stressors that may unmask latent vulnerabilities. This review combines the latest data and findings about the pathophysiology of β-thalassemia minor during pregnancy, its short-term outcomes on the mother and fetus, and its long-term impact on the child, as well as management techniques. A narrative review of PubMed-indexed studies (2000–2025) was conducted, including cohort and case–control studies, systematic reviews, meta-analyses, and international guidelines. Outcomes were organized by theme, and quantitative findings (prevalence, relative risks, odds ratios) were combined when available. Anemia is a common health issue for mothers. Literature mentions that the pooled incidence is between 30% and 40% during the third trimester, with ~5%of carriers needing a blood transfusion (mainly in iron-deficient or baseline Hb 6–8 g/dL cases). Meta-analyses have shown elevated risks of pre-eclampsia (odds ratio (OR) ~ 1.4, 95% confidence interval (CI) 1.1–1.8) and postpartum hemorrhage (PPH); however, estimates differ by region. The odds of preterm delivery (OR ~ 1.4), small-for-gestational-age (SGA) (OR ~ 1.5), and low birth weight (LBW) are slightly increased for carriers, and neonatal intensive care unit (NICU) admission rates are also higher for carriers. However, the risk of stillbirth is not always increased. The usual approach is iron supplementation guided by ferritin levels to prevent overload, personalized transfusion thresholds, and regular folate support. There is not much evidence for long-term consequences for children of carrier mothers since no research has followed more than 200 children born to carrier mothers into adulthood. However, maternal anemia is linked to slower growth, neurodevelopmental issues, and a higher risk of cardiometabolic problems in larger groups of pregnant women. However, maternal anemia is associated with slower growth, neurodevelopment, and higher cardiometabolic risk in larger groups of pregnant women. β-thalassemia minor during pregnancy usually has a mild, though significant, impact. While most pregnancies proceed without complications, this condition is associated with a significantly higher prevalence of anemia and other adverse postnatal outcomes. Consequently, the implementation of risk-stratified monitoring, smart supplementation, and standardized management protocols is essential. Prospective registries, mechanistic placental research, and long-term offspring cohorts are necessary to better understand long-term trends. Full article

Low birth weight (LBW) is associated with neonatal morbidity, mortality and long-term health complications. Global studies report an association between air pollution, such as tropospheric ozone, and LBW. This study aims to analyze the association between ozone exposure during pregnancy and LBW in 130 municipalities in rural and semi-urban Spain. We conducted a retrospective population-based cohort study using data from the Instituto Nacional de Estadística (INE) and air quality data from the Spanish Government for the 2001–2017 period. We performed descriptive analysis, logistic regression and linear regression analyses adjusted for various covariates. In addition, we fitted generalized additive models (GAMs) to estimate non-linear relationships. An association between decreased neonatal weight and high ozone exposure was found, especially in the first and second trimester. An increase in ozone concentration could lower neonatal weight but not enough evidence demonstrates an association with LBW. More research is needed to understand the impact of ozone exposure on neonates during pregnancy. Full article

Background/Objectives: Preterm birth (PTB) is a major public health concern worldwide, which may lead to detrimental maternal and neonatal outcomes. Maternal nutritional status, gestational weight gain (GWG), and lifestyle factors are potentially modifiable determinants of adverse pregnancy outcomes. This study examined the association between PTB and maternal GWG and assessed whether maternal dietary habits and lifestyle factors were related to GWG in women delivering preterm versus at term. Methods: A retrospective case–control study was conducted at a tertiary center in Hungary (MANOR Study, 2019). The case group included n = 100 women with PTB, while n = 200 matched term deliveries served as controls (1:2 ratio). Data were collected using a self-administered questionnaire and medical records. Pre-pregnancy body mass index (BMI) was categorized using standard definitions, while GWG was classified as inadequate, recommended, or excessive according to the US 2009 Institute of Medicine guidelines. A 7-item dietary index score was calculated based on gestational dietary habits. Results: Pre-pregnancy BMI distribution did not considerably differ between groups (p > 0.05); over one-third of women in both groups were overweight or had obesity (38.7% vs. 36.7%). Previous PTB (p < 0.001) and gestational hypertension (GHT) (p = 0.003) were more common among current PTB cases, while smoking, alcohol consumption, and gestational diabetes mellitus (GDM) showed negligible differences (p > 0.05)—28.0% of cases, and 34.5% of controls were classified as having healthy dietary habits, based on the dietary index score calculated. Inadequate GWG was more prevalent among PTB cases (49.0% vs. 26.8%), whereas excessive GWG was less frequent among cases (21.9% vs. 38.4%). Being within the recommended GWG range and the manifestation of gestational hypertension were associated with lower (aOR: 0.39; 95% CI: 0.18–0.87; p = 0.020) and higher (aOR: 3.43; 95% CI: 1.44–8.19; p = 0.005) odds of PTB, respectively. Conclusions: Inadequate GWG was more common in PTB, while excessive GWG was more frequent in term pregnancies. Fast-food consumption was associated with excessive GWG among term births. Optimizing GWG and improving maternal diet quality should be included as key, cross-cutting interventions targeting the improvement of antenatal care. Full article

Background/Objectives: Preterm infants are particularly vulnerable to nutritional deficiencies and electrolyte imbalances during the early stages of extrauterine life. To ensure optimal metabolic support, they often require the early initiation of “aggressive” parenteral nutrition (PN), which is a known risk factor for Refeeding Syndrome (RS), a potentially serious metabolic condition characterized by fluid and electrolyte disturbances, the most significant of which is hypophosphatemia. Hypophosphatemia can impair the metabolism, survival, and function of red blood cells, leading to a reduction in key intracellular metabolites and the development of a metabolic block that alters their quality and decreases their stability. It is therefore hypothesized that RS may contribute to the development of anemia of prematurity (AOP). At the same time, early enteral nutrition (EN) may promote metabolic adaptation and reduce exposure to the complications of prolonged parenteral support, potentially protecting against AOP. The primary aim of this study was to determine whether preterm infants who develop RS are at increased risk of AOP. A secondary aim was to evaluate whether early EN may act as a protective factor against the development of AOP. Methods: This retrospective observational study was conducted on infants with a gestational age ≤ 34 weeks and/or birth weight ≤ 1500 g, admitted to the Neonatal Intensive Care Unit of Policlinico Umberto I—Sapienza University of Rome, between January 2015 and November 2022. Infants diagnosed with AOP were classified as cases, while those without AOP served as the control group. Results: A total of 412 preterm infants were enrolled (110 cases, 302 controls). Refeeding Syndrome was significantly more frequent in infants with AOP (30.9% vs. 11.6%, p < 0.001). In the logistic regression model adjusted for gestational age, RS was independently associated with AOP (OR = 2.81; 95% CI: 1.55–5.10; p < 0.001), along with gestational age ≤ 34 weeks (OR = 7.10; 95% CI: 2.13–24.0; p = 0.001). Early enteral nutrition during the first week of life was associated with a significantly lower risk of AOP (OR = 0.12; 95% CI: 0.029–0.52; p = 0.005). The association between RS and AOP was confirmed in the model adjusted for birth weight (OR = 2.06; 95% CI: 1.16–3.79; p = 0.021). Infants with AOP showed significantly higher parenteral nutrition intake, delayed initiation of enteral feeding, and later achievement of full enteral nutrition compared with controls (all p < 0.001). Conclusions: RS is significantly associated with AOP in preterm infants, likely through pathophysiological mechanisms related to hypophosphatemia. Importantly, early EN may be a protective factor against AOP, suggesting that timely initiation and advancement in enteral feeding may counteract the metabolic derangements associated with intensive parenteral support. These findings support a nutritional approach that prioritizes early and progressive enteral nutrition as a strategy to reduce the risk of both RS and AOP. Further prospective studies are needed to confirm these associations and to define optimal EN protocols for this population. Full article