Objective:To investigate the therapeutic effects of Akkermansia muciniphila (AKK) on liver injury induced by cholestasis and its mechanisms in regulating bile acid metabolism. Methods:The cholestatic mouse model was established by bile duct ligation (BDL). A total of 35 male C57BL/6J mice (8 weeks old) were divided into 5 groups using a random numder table method (7 mice per group): group A (control group), group B (BDL group), group C (BDL+AKK group), group Z (BDL+AKK+Z/E-guggulsterone group), and group G (BDL+AKK+Gly-β-muricholic acid group). Preoperative and postoperative changes in liver function and bile acid metabolism indicators was observed of mice in groups A, B, and C. The liver function and fibrosis markers were compared between groups, as well as serum, liver, and fecal total bile acid levels, fecal bile acid composition, liver histopathology, and the mRNA expression of key proteins involved in the bile acid enterohepatic circulation and the farnesoid X receptor (FXR) signaling pathway were compared. Multiple groups of data were compared using analysis of variance or nonparametric Kruskal Wallis H test. Results:Twelve days after BDL, in groups A, B, and C, mice in group C exhibited milder postoperative jaundice and their body weights on postoperative days 4-5 and 7-11 were heavier than those in group B mice (all P<0.05). The liver tissues of mice in group C were milder than those in group B in terms of appearance, histopathology, inflammation and liver fibrosis (all P<0.05). The levels of serum alanine aminotransferase, aspartate aminotransferase, as well as the expression levels of liver α-smooth muscle actin and type Ⅰ collagen, and the levels of total liver bile acid and fecal β-murine bile acid in the C group mice were all lower than those of group B mice ((46±20) vs. (90±34) U/L, (96±17) vs.(122±31) U/L, (2.01±0.11)% vs. (7.55±0.21)%, (1.92±0.10)% vs. (7.28±0.51)%, (62±14) vs. (124±39) μmol/mg, 3 052 (1 522, 6 406) vs. 14 756 (6 582, 33 474) ng/g,all P<0.05). And the mRNA expression levels of cholesterol 7α-hydroxylase and bile salt export pump of the ileum, etc. in group C mice were lower than those in group B mice (all P<0.05), while the mRNA expression levels of FXR and fibroblast growth factor 15 in the intestine were higher than those in group B mice (all P<0.05). In groups B, C, Z, and G, compared with group C, mice in groups Z and G had aggravated liver injury and fibrosis, increased total bile acid levels in the liver, and increased serum alanine aminotransferase, total bilirubin, and expression levels of liver α-smooth muscle activator protein and type I collagen (all P<0.05). There was no statistically difference in the above indicators between group Z and group G (all P<0.05). Conclusion:AKK reduces liver bile acid synthesis, regulates bile acid metabolism, alleviate liver function damage and fibrosis, and improves clinical phenotypes by activating the intestinal FXR-fibroblast growth factor 15 signaling pathway.

Objective:To investigate the association between small vulnerable newborn (SVN) phenotypes and the risk of neurodevelopmental delay at the age of 1 year.Methods:A prospective cohort study was conducted. A total of 25 860 singleton infants from "The Born in Guangzhou Cohort Study" who completed the Gesell developmental scale assessment at 1 year of age between January 2013 and June 2025 were included. Maternal sociodemographic characteristics, and other information were collected using a self-administered questionnaire, and maternal pregnancy-related information and neonatal birth data were extracted from medical records. Global developmental delay (GDD) was defined as a developmental quotient below 86 in ≥3 domains of the Gesell developmental scale, which assesses the adaptive, gross motor, fine motor, language, and personal-social domains. The random forest algorithm was employed for missing data imputation. Based on prematurity, small for gestational age (SGA), and low birth weight (LBW), newborns were categorized into 6 phenotypes: preterm-SGA-LBW, preterm-appropriate for gestational age (AGA)-LBW, preterm-AGA-nonLBW, term-SGA-LBW, term-LBW-only or term-SGA-only, and term-AGA-nonLBW phenotype. Among these, the first 5 were classified as SVN phenotypes, and the last one served as the reference group. Inter-group comparisons were performed using analysis of variance (ANOVA), χ2 tests, or Kruskal-Wallis test, as appropriate.?? Multivariable robust Poisson regression models were applied to analyze the association of different SVN phenotypes with the risks of GDD and developmental delays in specific domains, with stratified analyses by sex. Results:Among the 25 860 infants, 13 719 (53.1%) were male and 12 141 (46.9%) were female. The gestational age at birth was 39.4 (38.6, 40.0) weeks. The overall detection rate of GDD at 1 year of age was 3.7% (962/25 860). The rates of delay across developmental domains, in descending order, language in 8 134 cases (31.5%), gross motor in 4 488 cases (17.4%), personal-social in 1 271 cases (4.9%), adaptive in 1 262 cases (4.9%), and fine motor in 621 cases (2.4%). Compared with the reference group, preterm-AGA-LBW, preterm-SGA-LBW, preterm-AGA-noneLBW, and term-SGA-LBW phenotypes were all associated with an increased risk of GDD, with the adjusted RR (95% CI) of 6.07(5.01-7.35), 4.81(3.11-7.46), 2.10(1.54-2.88) and 1.89(1.29-2.76) respectively.The preterm-AGA-noneLBW phenotype was all associated with an increased risk of delay in gross motor, language and personal-social functional domains (all P<0.05). The term-SGA-LBW phenotype was associated with an increased risk of delay in gross motor, fine motor and personal-social functional domains (all P<0.01). Whereas the term-LBW-only or term-SGA-only phenotype showed no statistically association with developmental delay in any functional domain (all P≥0.05). Conclusion:The combined classification based on gestational age and birth weight helps identify infants at high risk for neurodevelopmental delay at 1 year of age, suggesting that it may offer a reference for the rational allocation of clinical resources.

Objective:To investigate the diagnostic consistency of extrauterine growth restriction (EUGR) assessed by the Fenton 2013 preterm growth charts (Fenton 2013) and the growth charts by International Fetal and Newborn Growth Consortium for the 21st Century (IG-21).Methods:This multicenter retrospective cohort study included 5 591 preterm infants with a gestational age (GA) at birth of less than 32 weeks admitted to 19 member hospitals of the Neonatal Perinatal Collaborative Network of Suxinyun from January 1 st, 2019, to December 31 st, 2024. Clinical data including baseline characteristics, complications, feeding practices and anthropometrics were processed and analyzed. EUGR was assessed using both the Fenton 2013 and the IG-21. A decrease in weight Z-score at discharge compared to admission by more than 1 was defined as longitudinal EUGR, and discharge weight below the P10 for the corresponding corrected GA was defined as cross-sectional EUGR. Diagnostic consistency was assessed using the Kappa coefficient between the 2 standards, and diagnostic performance of the 2 standards was compared using the McNemar test. Risk factors for EUGR under different definitions were analyzed using univariate analysis and multivariate Logistic regression analysis. Results:A total of 5 591 preterm infants were included, with a GA at birth of (29.7±1.6) weeks and a birth weight of (1 360±315) g and at discharge with a corrected GA of (36.3±2.0) weeks and weight of (2 246±370) g. Detection rates of cross-sectional and longitudinal EUGR diagnosed by Fenton 2013 were both higher than those by IG-21 (37.0% (2 214/5 991) vs. 23.7% (1 324/5 591), 61.1% (3 662/5 991) vs. 30.7% (1 714/5 591), χ2=326.77 and 1 358.05, both P<0.001). Using Fenton 2013 as a reference, IG-21 demonstrated superior diagnostic value and consistency in identifying cross-sectional EUGR compared with longitudinal EUGR (sensitivity of 100.0% (3 377/3 377) vs. 99.6% (1 922/1 929), specificity of 59.8% (1 324/2 214) vs. 46.6% (1 707/3 662), positive predictive value of 79.1% (3 377/4 267) vs. 49.6% (1 922/3 877), negative predictive value of 100.0% (1 324/1 324) vs. 99.6% (1 707/1 714), accuracy of 84.1% (4 701/5 591) vs. 64.9% (3 629/5 591), and Kappa 0.64 vs. 0.37, all P<0.001). In multivariate Logistic regression models, risk factors common to EUGR across both standards included smaller GA at birth, lower birth weight, boy, early-onset sepsis, late-onset sepsis and the elder age at full enteral feeding (all P<0.05). Hemodynamically significant patent ductus arteriosus remained an independent risk factor for longitudinal EUGR regardless of whether by the Fenton 2013 or IG-21 standard (adjust odds ratio ( aOR) =1.25 and 1.27, 95% CI 1.09-1.42 and 1.11-1.45). In addition, under the IG-21 standard, severe bronchopulmonary dysplasia was an independent risk factor for cross-sectional EUGR ( aOR=1.54, 95% CI 1.00-2.38), while severe necrotizing enterocolitis was an independent risk factor for longitudinal EUGR ( aOR=2.18, 95% CI 1.01-4.73). Conclusions:IG-21 showed lower detection rates of both cross-sectional and longitudinal EUGR than Fenton 2013, suggesting greater clinical applicability of IG-21 by reducing overdiagnosis while maintaining sensitivity for predicting complications. Across both standards, cross-sectional EUGR facilitates early identification of growth restriction, whereas longitudinal EUGR better tracks dynamic growth patterns and complications of preterm infants.

Objective:To summarize the clinical features of children with anomalous origin of coronary artery (AOCA) who received extracorporeal membrane oxygenation (ECMO) support.Methods:A case series study was conducted. Clinical data was collected from 6 children who were diagnosed with AOCA by coronary computed tomography angiography or digital subtraction angiography and received ECMO support in the Pediatric Intensive Care Unit of Henan Provincial People′s Hospital between January 2020 and August 2024. Descriptive analysis was performed on their clinical features, laboratory test results, point-of-care echocardiography results, imaging findings, surgical management, and outcomes.Results:Among the 6 children (3 males and 3 females), the age of onset was 12.5 (11.0, 13.0) years. All 6 patients were transported from other hospitals under ECMO support. Five patients were admitted with chief complaints of "cardiac arrest after strenuous activity, syncope after strenuous activity, or heart failure" and were initially diagnosed with fulminant myocarditis or cardiomyopathy. All 6 children had significantly elevated troponin and B-type natriuretic peptide levels upon admission. Point-of-care echocardiography revealed segmental left ventricular systolic dysfunction in all 6 children, and AOCA was detected in 2 cases based on bedside ultrasound. ECMO was successfully weaned in 5 children. All 6 cases were diagnosed with AOCA. Four children underwent surgical coronary artery correction, one received a heart transplantation, and one missed the optimal window for surgical correction. Heart transplantation was recommended for the latter, but the parents declined, and the patient was discharged. During the follow-up until August 2025, all 6 children survived.Conclusions:AOCA in children is prone to misdiagnosis as other diseases in the early stage. Timely ECMO support provides the possibility of surgery or heart transplantation for children experiencing acute ischemic and hypoxic episodes due to AOCA, improving survival rates.

Objective:To assess the status of undernutrition and appropriate catch-up growth in extremely preterm infants within 24 months of corrected age (CA).Methods:A retrospective cohort study was conducted. A total of 422 extremely preterm infants born at Shenzhen Maternity and Child Healthcare Hospital, Women and Children's Medical Center, Southern Medical University from January 2017 to December 2022 and followed up until 24 months of CA were enrolled. The extremely preterm infants were grouped by gestational age at birth (<25, 25-26, 27 weeks), birth weight (<500, 500-749, 750-999,≥1 000 g), weight for gestational age (large for gestational age (LGA), appropriate for gestational age (AGA), small for gestational age (SGA)) and sex. Weight data within 24 months of CA were collected every 3 months. Nutritional insufficiency, growth rate, and achievement of adequate catch-up growth were analyzed during the period from 0 to 24 months of CA. Z-score method was used to analyze data. Fenton 2013 preterm growth charts (Fenton 2013) were used before 40 weeks of corrected gestational age, and World Health Organization child growth standards (2009) fitted Z-scores were applied from 40 weeks of CA. Changes in weight Z-scores of extremely preterm infants from 0 to 24 months of CA were observed and compared, the occurrence of moderate to severe malnutrition and growth retardation was determined, nutritional insufficiency was assessed, and growth rate as well as the achievement of appropriate catch-up growth were analyzed. The Lambda-mu-sigma method combined with the Z-score fitting model was used to fit and analyze the distribution characteristics of weight percentiles in extremely preterm infants. The Chi-square test was used to compare differences among groups.Results:A total of 422 extremely preterm infants were included, with a gestational age at birth of 26.3(25.4, 27.2) weeks and a birth weight of (880±177) g. Among them, 238 were males and 184 were females; 36 cases (8.5%) were LGA, and 16 cases (3.8%) were SGA. During follow-up within 24 month of CA, 89 cases (21.1%) developed moderate to severe malnutrition. When compared separately among different birth weight and gestational age at birth groups, there had both statistically differences in the incidence of moderate to severe malnutrition ( χ2=42.94 and 9.17, both P<0.05). The incidence was the highest in the birth weight of CA<500 g group and the <25 weeks gestational age at birth group, while it was the lowest in the birth weight of CA≥1 000 g group and the 27 weeks gestational age at birth group in their respective groups. Growth retardation occurred in 5.2% (22/422). However, there had statistically differences in the incidence of growth retardation among different birth weight and gestational age at birth groups, in each grouped time interval ( χ2=21.61 and 4.30, both P<0.05). The proportions of rapid growth were relatively high in the 0-3 months and 3-6 months of CA groups, which were 96 cases (27.4%) and 98 cases (26.6%), respectively. Overall, appropriate catch-up growth was achieved in 341 cases (80.8%) from 0 to 24 months of CA. There had statistically differences in the completion rate of appropriate catch-up growth among different birth weight and gestational age at birth groups ( χ2=23.65 and 7.08, both P<0.05). The completion rate was the highest in the birth weight of CA<500 g group and the <25 weeks of gestational age at birth group, while it was the lowest in the birth weight of CA≥1 000 g group and the 27 weeks of gestational age at birth group. Conclusions:The lower the birth weight and gestational age of extremely preterm infants, the higher the incidence of moderate to severe malnutrition and the lower the achievement rate of adequate catch-up growth within 24 months of CA. The period of 0-6 months of CA is the critical window for catch-up in extremely preterm infants.

Objective:To investigate the main causes of failed endoscopic retrograde cholangiopancreatography (ERCP) in children and the remedial treatment strategies.Methods:This retrospective cohort study analyzed the clinical data of 21 children who experienced failed ERCP at Beijing Children′s Hospital, Capital Medical University between January 2021 and December 2024. Data was collected included demographic information, clinical diagnoses, and ERCP outcomes. The annually trend in the ERCP failure rate was analyzed. Patients were categorized by etiology into the following groups: chronic pancreatitis, post-surgical status, pancreatic trauma, pancreas divisum, non-neoplastic pancreatic lesions, and ulcerative colitis. The relationship between etiologies and ERCP failure was analyzed by Fisher exact test.Results:A total of 175 ERCP procedures were included, of which 21 procedures failed (12.0%). The failure rate decreased annually from 2021 to 2024: 18.2% (4/22), 13.2% (5/38), 11.4% (5/44), and 9.9% (7/71), respectively. The etiological distribution among the 21 failed cases was as follows: chronic pancreatitis 28.6% (6/21), pancreatic duct stenosis following pancreatic trauma 23.8% (5/21), post-surgical status 14.3% (3/21), pancreas divisum 9.5% (2/21), acute pancreatitis 9.5% (2/21), non-neoplastic pancreatic lesions 9.5% (2/21), and pancreatic duct stenosis associated with ulcerative colitis 4.8% (1/21). Remedial treatments included surgical intervention (2 cases), ultrasound-guided percutaneous drainage (3 cases), and repeat ERCP (2 cases). For post-surgical and pancreatic trauma patients, failure was primarily due to bile duct stenosis, pancreatic duct stenosis, or pancreaticobiliary duct disruption. Active surgical interventions such as cholangiojejunostomy and pancreaticojejunostomy, and ultrasound-guided drainage following ERCP failure led to significant clinical improvement.Conclusions:A stratified management approach guided by etiology is essential following failed ERCP in children. Early and active remedial treatment, particularly surgical interventions, is recommended for post-surgical and pancreatic trauma cases.

Objective:To explore the clinical characteristics, diagnosis and treatment strategies, and prognosis of pulmonary embolism (PE) complicating childhood rheumatic diseases.Methods:A retrospective case series study was performed on the demographic data, laboratory indicators, imaging features, treatment regimens, and follow-up data of 8 children with rheumatic diseases complicated by PE who were admitted to the Department of Rheumatology and Immunology, Capital Center for Children′s Health, Capital Medical University from January 2014 to October 2023.Results:Among the 8 children, there were 4 boys and 4 girls, with an age of 12.0 (7.5, 13.0) years. Among the primary diseases, there were 3 cases of systemic lupus erythematosus, 2 cases of Beh?et′s disease, 2 cases of Takayasu arteritis, and 1 case of antiphospholipid syndrome. All children developed PE during the active phase of the primary disease. PE was detected at the onset of the primary disease in 3 cases, and the median time from the diagnosis of the primary disease to the development of PE was 10.0 (6.0, 25.0) months in the remaining 5 cases. Fever was present in all 8 children, 4 cases were accompanied by chest tightness, dyspnea, etc., and 2 cases only presented with fever. Laboratory examinations revealed the following results: erythrocyte sedimentation rate was 42.0 (17.0, 78.0) mm/1 h, high-sensitivity C-reactive protein was 12.7 (2.6, 78.7) mg/L, white blood cell count was 9.6 (7.2, 18.7)×10 9/L; D-dimer was 2.3 (0.9, 6.2) mg/L; and hemoglobin was (109±16) g/L.Imaging examinations revealed that 5 cases had involvement of the bilateral lower pulmonary arteries, 5 cases had peripheral embolism, and 3 cases had central PE. Complications included 3 cases of deep vein thrombosis, 2 cases of intracranial venous sinus thrombosis, and 1 case of mild pulmonary hypertension.In terms of treatment, 7 cases received anticoagulation with heparin followed by warfarin. Immunomodulation was mainly based on glucocorticoids combined with immunosuppressants, and 4 cases were combined with biological agents. The follow-up time of 4.17 (1.75, 7.17) years, the time for complete absorption of PE was 10.5 (6.0, 18.0) months; all 8 children had no target events, with no recurrence or chronic thromboembolic pulmonary hypertension, and the pulmonary artery remodeling was good. Conclusions:PE complicating childhood rheumatic diseases is closely related to the activity of the primary disease. The clinical manifestations are insidious, with fever as the main symptom. Imaging examination is the key to diagnosis.Early adoption of heparin followed by warfarin anticoagulation and glucocorticoids combined with immunosuppressants and (or) biological agents to control the primary disease can achieve a favorable prognosis.

Objective:To investigate the clinical characteristics of infantile cholestasis caused by IFT122 gene variants and the molecular mechanism underlying its impact on primary cilia.Methods:The clinical data of an infant with cholestasis from the Children′s Hospital of Fudan University in September 2022 were retrospectively analyzed. The whole-exome sequencing was performed to identify candidate variants, which were validated by Sanger sequencing in the family. Immortalized cell lines were generated using lentiviral infection, followed by immunofluorescence staining to assess the impact of the variants on primary cilia. Intergroup comparisons were performed using the independent sample t-test and Mann-Whitney U test .Results:The proband was a 4-month-old male infant presenting with jaundice, distinctive facial features, and sagittal craniosynostosis. Blood biochemistry indicated elevated direct bilirubin, total bile acids, and transaminases, with markedly increased γ-glutamyltransferase (GGT). Liver pathology demonstrated giant cell hepatitis with cholestasis and bile duct dysplasia. Genetic analysis identified compound heterozygous variants in IFT122 (NM_052989.3) gene c.88G>C (p.Ala30Pro) and c.240G>C (p.Trp80Cys), which co-segregated with the disease in the family. Immunofluorescence analysis demonstrated that the IFT122 gene compound heterozygous missense variants not only significantly reduced the proportion of cilia-positive cells but also led to aberrant ciliary localization of ADP-ribosylation factor-like protein 13B (ARL13B).In addition, ciliary deposition with phosphatidylinositol polyphosphate 5-phosphatase type Ⅳ (INPP5E) was reduced. All differences were statistically significant (all P<0.05). Conclusion:The compound heterozygous missense variants in IFT122 gene not only impair ciliogenesis but also disrupt the ciliary localization of ARL13B and INPP5E, ultimately resulting in high-GGT infantile cholestasis.

Objective:To investigate the therapeutic effects of Akkermansia muciniphila (AKK) on liver injury induced by cholestasis and its mechanisms in regulating bile acid metabolism. Methods:The cholestatic mouse model was established by bile duct ligation (BDL). A total of 35 male C57BL/6J mice (8 weeks old) were divided into 5 groups using a random numder table method (7 mice per group): group A (control group), group B (BDL group), group C (BDL+AKK group), group Z (BDL+AKK+Z/E-guggulsterone group), and group G (BDL+AKK+Gly-β-muricholic acid group). Preoperative and postoperative changes in liver function and bile acid metabolism indicators was observed of mice in groups A, B, and C. The liver function and fibrosis markers were compared between groups, as well as serum, liver, and fecal total bile acid levels, fecal bile acid composition, liver histopathology, and the mRNA expression of key proteins involved in the bile acid enterohepatic circulation and the farnesoid X receptor (FXR) signaling pathway were compared. Multiple groups of data were compared using analysis of variance or nonparametric Kruskal Wallis H test. Results:Twelve days after BDL, in groups A, B, and C, mice in group C exhibited milder postoperative jaundice and their body weights on postoperative days 4-5 and 7-11 were heavier than those in group B mice (all P<0.05). The liver tissues of mice in group C were milder than those in group B in terms of appearance, histopathology, inflammation and liver fibrosis (all P<0.05). The levels of serum alanine aminotransferase, aspartate aminotransferase, as well as the expression levels of liver α-smooth muscle actin and type Ⅰ collagen, and the levels of total liver bile acid and fecal β-murine bile acid in the C group mice were all lower than those of group B mice ((46±20) vs. (90±34) U/L, (96±17) vs.(122±31) U/L, (2.01±0.11)% vs. (7.55±0.21)%, (1.92±0.10)% vs. (7.28±0.51)%, (62±14) vs. (124±39) μmol/mg, 3 052 (1 522, 6 406) vs. 14 756 (6 582, 33 474) ng/g,all P<0.05). And the mRNA expression levels of cholesterol 7α-hydroxylase and bile salt export pump of the ileum, etc. in group C mice were lower than those in group B mice (all P<0.05), while the mRNA expression levels of FXR and fibroblast growth factor 15 in the intestine were higher than those in group B mice (all P<0.05). In groups B, C, Z, and G, compared with group C, mice in groups Z and G had aggravated liver injury and fibrosis, increased total bile acid levels in the liver, and increased serum alanine aminotransferase, total bilirubin, and expression levels of liver α-smooth muscle activator protein and type I collagen (all P<0.05). There was no statistically difference in the above indicators between group Z and group G (all P<0.05). Conclusion:AKK reduces liver bile acid synthesis, regulates bile acid metabolism, alleviate liver function damage and fibrosis, and improves clinical phenotypes by activating the intestinal FXR-fibroblast growth factor 15 signaling pathway.

Objective:To investigate the association between small vulnerable newborn (SVN) phenotypes and the risk of neurodevelopmental delay at the age of 1 year.Methods:A prospective cohort study was conducted. A total of 25 860 singleton infants from "The Born in Guangzhou Cohort Study" who completed the Gesell developmental scale assessment at 1 year of age between January 2013 and June 2025 were included. Maternal sociodemographic characteristics, and other information were collected using a self-administered questionnaire, and maternal pregnancy-related information and neonatal birth data were extracted from medical records. Global developmental delay (GDD) was defined as a developmental quotient below 86 in ≥3 domains of the Gesell developmental scale, which assesses the adaptive, gross motor, fine motor, language, and personal-social domains. The random forest algorithm was employed for missing data imputation. Based on prematurity, small for gestational age (SGA), and low birth weight (LBW), newborns were categorized into 6 phenotypes: preterm-SGA-LBW, preterm-appropriate for gestational age (AGA)-LBW, preterm-AGA-nonLBW, term-SGA-LBW, term-LBW-only or term-SGA-only, and term-AGA-nonLBW phenotype. Among these, the first 5 were classified as SVN phenotypes, and the last one served as the reference group. Inter-group comparisons were performed using analysis of variance (ANOVA), χ2 tests, or Kruskal-Wallis test, as appropriate.?? Multivariable robust Poisson regression models were applied to analyze the association of different SVN phenotypes with the risks of GDD and developmental delays in specific domains, with stratified analyses by sex. Results:Among the 25 860 infants, 13 719 (53.1%) were male and 12 141 (46.9%) were female. The gestational age at birth was 39.4 (38.6, 40.0) weeks. The overall detection rate of GDD at 1 year of age was 3.7% (962/25 860). The rates of delay across developmental domains, in descending order, language in 8 134 cases (31.5%), gross motor in 4 488 cases (17.4%), personal-social in 1 271 cases (4.9%), adaptive in 1 262 cases (4.9%), and fine motor in 621 cases (2.4%). Compared with the reference group, preterm-AGA-LBW, preterm-SGA-LBW, preterm-AGA-noneLBW, and term-SGA-LBW phenotypes were all associated with an increased risk of GDD, with the adjusted RR (95% CI) of 6.07(5.01-7.35), 4.81(3.11-7.46), 2.10(1.54-2.88) and 1.89(1.29-2.76) respectively.The preterm-AGA-noneLBW phenotype was all associated with an increased risk of delay in gross motor, language and personal-social functional domains (all P<0.05). The term-SGA-LBW phenotype was associated with an increased risk of delay in gross motor, fine motor and personal-social functional domains (all P<0.01). Whereas the term-LBW-only or term-SGA-only phenotype showed no statistically association with developmental delay in any functional domain (all P≥0.05). Conclusion:The combined classification based on gestational age and birth weight helps identify infants at high risk for neurodevelopmental delay at 1 year of age, suggesting that it may offer a reference for the rational allocation of clinical resources.