Peso al nacer en el noroeste argentino. Comparación con una referencia nacional y un estándar internacional / Birth weight in the Northwest region of Argentina. Comparison with a national reference and an international standard

Introducción. El tamaño al nacer se encuentra sujeto a influencias genéticas y ambientales; la altura geográfica es muy influyente. El peso al nacer (PN) es el indicador más utilizado para evaluarlo; existen diferentes estándares y referencias. Debido a la variabilidad de la distribución del PN en relación con la altura en la provincia de Jujuy (Argentina), este trabajo analiza la distribución percentilar del PN para tierras altas (TA) y tierras bajas (TB) jujeñas según edad gestacional (EG) y sexo, y su comparación con una referencia nacional y el estándar internacional INTERGROWTH-21st (IG-21). Población y métodos. Se analizaron los registros de 78 524 nacidos vivos en Jujuy en el período 20092014. Utilizando el método LMS, se estimaron los percentiles 3, 10, 50, 90 y 97 de PN/EG por sexo, para TA (≥2000 msnm), TB (<2000 msnm) y el total provincial, y se compararon gráficamente con la referencia poblacional argentina de Urquía y el estándar IG-21. La significación estadística se determinó mediante la prueba de Wilcoxon. Resultados. El PN en Jujuy presentó distribución heterogénea, con diferencias estadísticamente significativas (p <0,05) entre TB y TA. Al comparar con la referencia nacional y el estándar IG-21, se observaron diferencias por altitud, principalmente en los percentiles 90 y 97 para ambas regiones, y en los percentiles 3 y 10 en TA comparados con el estándar. Conclusiones. Se observó variabilidad de la distribución del PN asociada a la altura geográfica, por lo que, para evaluar el crecimiento intrauterino, resulta fundamental incluir la EG y el contexto donde transcurre la gestación.

Introduction. Size at birth is subject to genetic and environmental influences; altitude is highly influential. Birth weight (BW) is the most widely used indicator to assess size at birth; different standards and references are available. Due to the variability in BW distribution in relation to altitude in the province of Jujuy (Argentina), the purpose of this study is to analyze the percentile distribution of BW in the highlands (HL) and the lowlands (LL) of Jujuy based on gestational age (GA) and sex and compare it with a national reference and the INTERGROWTH-21 st (IG-21) international standard. Population and methods. The records of 78 524 live births in Jujuy in the 2009­2014 period were analyzed. Using the LMS method, the 3 rd, 10 th, 50 th, 90 th, and 97 th percentiles of BW/GA by sex were estimated for the HL (≥ 2000 MASL), the LL (< 2000 MASL), and the total for Jujuy, and compared with the Argentine population reference by Urquía and the IG-21 standard using growth charts. The statistical significance was established using the Wilcoxon test. Results. BW in Jujuy showed a heterogeneous distribution, with statistically significant differences (p < 0.05) between the LL and the HL. When compared with the national reference and the IG-21 standard, differences in terms of altitude were observed, mainly in the 90 th and 97 th percentiles for both regions and the 3 rd and 10 th percentiles in the HL compared with the international standard. Conclusions. BW distribution varied in association with altitude; therefore, to assess intrauterine growth, it is critical to include GA and the environment in which the pregnancy takes place.

Association between congenital hypothyroidism and in-hospital adverse outcomes in very low birth weight infants / 中华儿科杂志

Objective: To investigate the association between congenital hypothyroidism (CH) and the adverse outcomes during hospitalization in very low birth weight infants (VLBWI). Methods: This prospective, multicenter observational cohort study was conducted based on the data from the Sino-northern Neonatal Network (SNN). Data of 5 818 VLBWI with birth weight <1 500 g and gestational age between 24-<37 weeks that were admitted to the 37 neonatal intensive care units from January 1st, 2019 to December 31st, 2022 were collected and analyzed. Thyroid function was first screened at 7 to 10 days after birth, followed by weekly tests within the first 4 weeks, and retested at 36 weeks of corrected gestational age or before discharge. The VLBWI were assigned to the CH group or non-CH group. Chi-square test, Fisher exact probability method, Wilcoxon rank sum test, univariate and multivariate Logistic regression were used to analyze the relationship between CH and poor prognosis during hospitalization in VLBWI. Results: A total of 5 818 eligible VLBWI were enrolled, with 2 982 (51.3%) males and the gestational age of 30 (29, 31) weeks. The incidence of CH was 5.5% (319 VLBWI). Among the CH group, only 121 VLBWI (37.9%) were diagnosed at the first screening. Univariate Logistic regression analysis showed that CH was associated with increased incidence of extrauterine growth retardation (EUGR) (OR=1.31(1.04-1.64), P<0.05) and retinopathy of prematurity (ROP) of stage Ⅲ and above (OR=1.74(1.11-2.75), P<0.05). However, multivariate Logistic regression analysis showed no significant correlation between CH and EUGR, moderate to severe bronchopulmonary dysplasia, grade Ⅲ to Ⅳ intraventricular hemorrhage, neonatal necrotizing enterocolitis in stage Ⅱ or above, and ROP in stage Ⅲ or above (OR=1.04 (0.81-1.33), 0.79 (0.54-1.15), 1.15 (0.58-2.26), 1.43 (0.81-2.53), 1.12 (0.70-1.80), all P>0.05). Conclusion: There is no significant correlation between CH and in-hospital adverse outcomes, possibly due to timely diagnosis and active replacement therapy.

Ultra-processed food consumption during pregnancy and newborn weight / Consumo de alimentos ultraprocessados durante a gestação e peso ao nascer do recém-nascido

Abstract Objectives: to assess the association between pregnant women's consumption of ultra-processed foods and newborn body weight. Methods: prospective study with pregnant women (n=214) selected from all Basic Health Units in the city of Pinhais, Paraná. Socioeconomic, demographic, and health data were collected. Food consumption data were assessed using a 24-hour dietary recall and tabulated with GloboDiet software. Daily relative energy intake of ultra-processed food was estimated and logistic regression analysis was utilized. The infuence of covariates on the association analysis was also explored (e.g., income and education). Results: ultra-processed foods contributed to 26.9% of pregnant women's total energy intake. About 5.7% of newborns were classifed as small-for-gestational-age and 10.7% as large-for-gestational-age. A borderline statistically signifcant association was observed between large-for-gestational-age newborn weight and maternal consumption of ultra-processed foods (OR= 1.027; p=0.048). Additionally, family income was associated with the consumption of ultra-processed foods (OR= 0.144; p=0.008). With each additional 1% consumption of ultra-processed foods, mothers' likelihood of having large-for-gestational-age babies increased by about 2.7%. Conclusions: the study reveals a trend of positive association between the weight of large-for-gestational-age newborns and the consumption of ultra-processed foods by pregnant women, but not for small-for-gestational-age children.

Resumo Objetivos: avaliar a associação entre o consumo de alimentos ultraprocessados por gestantes e o peso de recém-nascidos. Métodos: estudo prospectivo com gestantes (n=214) selecionadas em Unidades Básicas de Saúde em Pinhais, Paraná. Dados socioeconômicos, demográfcos e de saúde foram coletados. Dados de consumo alimentar foram coletados por recordatório de 24-horas físico e entrados no software GloboDiet. O consumo diário relativo de energia proveniente de alimentos ultraprocessados foi estimado e a análise de regressão logística foi utilizada, considerando covariáveis como renda familiar e escolaridade. Resultados: o consumo de alimentos ultraprocessados pelas gestantes representou 26,9% da energia total. Cerca de 5,7% de recém-nascidos foram classifcados como pequenos para idade gestacional (PIG) e 10,7% como grandes para idade gestacional (GIG). Foi observada uma associação estatisticamente signifcativa limítrofe entre o peso dos recém-nascidos GIG e o consumo materno de alimentos ultraprocessados (OR= 1,027; p=0,048). Além disso, a renda familiar esteve associada com o consumo de alimentos ultraprocessados (OR=0,144; p=0,008). A cada 1% adicional de consumo de alimentos ultraprocessados, a probabilidade de as mães terem recém-nascidos GIG aumentou cerca de 2,7%. Conclusões: o estudo revela uma tendência de associação positiva entre o peso de recém-nascidos GIG e o consumo de alimentos ultraprocessados por mulheres grávidas, mas não para crianças PIG.

Valoración del margen de error ecográfico entre el peso fetal estimado y el peso al nacer en la Maternidad del Hospital de Clínicas / Assessment of the ultrasound margin of error between the estimated fetal weight and the weight at birth in the Maternity of the Hospital de Clínicas / Avaliação da margem de erro ultrassonográfica entre o peso fetal estimado e o peso ao nascer na Maternidade do Hospital de Clínicas

Introducción: La valoración ultrasonográfica del peso fetal permite valorar el crecimiento y bienestar fetal pudiendo estimar el peso al nacimiento, factor determinante para el pronóstico vital. Objetivos: Determinar el margen de error ecográfico del peso fetal estimado (PFE) en relación con el peso al nacer de los neonatos de la Maternidad del Hospital de Clínicas entre los años 2020 y 2022 Materiales y Métodos: Se realizó un estudio observacional, descriptivo y transversal en mujeres que tuvieron un parto en el lugar y el período mencionado, y que contaban con ecografía obstétrica de crecimiento realizada con menos de 7 días respecto al nacimiento. Se calculó el error del PFE mediante la fórmula: (Peso al Nacer - Peso Fetal Estimado) / Peso al Nacer) x 100. Se contrastó el error del peso fetal estimado con el índice de masa corporal, diabetes y estados hipertensivos del embarazo, utilizando t de Student y con la edad gestacional y edad materna mediante el índice de Pearson tomando valores estadísticamente significativos menores a 0,05. Resultados: Se incluyeron 258 pacientes. El margen de error ecográfico del PFE fue de 8,3% DE ± 7. Se obtuvo un valor p para el IMC de 0,228, diabetes p 0,915, estados hipertensivos p 0,967, días en que se realizaba la ecografía p 0,5 y edad gestacional el p 0,001. Conclusiones: El margen de error ecográfico del PFE se encuentra por debajo de los parámetros internacionales. Se encontró asociación estadísticamente significativa con la edad gestacional, no así con las otras variables.

Introduction: Ultrasonographic assessment of fetal weight allows assessment of fetal growth and well-being and can estimate birth weight, a determining factor for vital prognosis. Objectives: Determine the ultrasound margin of error of the estimated fetal weight (EFP) in relation to the birth weight of neonates at the Maternity Hospital of the Hospital de Clínicas between the years 2020 and 2022. Materials and Methods: An observational, descriptive and cross-sectional study was carried out on women who had their birth in the aforementioned place and period and who had an obstetric growth ultrasound performed less than 7 days after birth. The error of the EPF was calculated using the formula: (Birth Weight - Estimated Fetal Weight) / Birth Weight) x 100. The error of the estimated fetal weight was contrasted with the body mass index, diabetes and hypertensive state of pregnancy, using Student's t and with gestational age and maternal age using the Pearson index taking statistically significant values ​​less than 0.05. Results: 258 patients were included. The ultrasound margin of error of the EPF was 8.3% SD ± 7. A p value was obtained for BMI of 0.228, diabetes p 0.915, hypertensive states p 0.967, days in which the ultrasound was performed p 0.5 and age gestational p 0.001. Conclusions: The ultrasound margin of error of the EPF is below the international parameters. Statistically significant associations were found with gestational age, but not with the other variables.

Introdução: A avaliação ultrassonográfica do peso fetal permite avaliar o crescimento e bem-estar fetal e pode estimar o peso ao nascer, fator determinante para o prognóstico vital. Objetivos: Determinar a margem de erro ultrassonográfica do peso fetal estimado (PFE) em relação ao peso ao nascer dos neonatos atendidos na Maternidade do Hospital de Clínicas entre os anos de 2020 e 2022. Materiais e Métodos: Foi realizado um estudo observacional, descritivo e transversal com mulheres que tiveram o parto no local e período mencionados e que realizaram ultrassonografia obstétrica de crescimento menos de 7 dias após o nascimento. O erro do PFE foi calculado pela fórmula: (Peso ao Nascer - Peso Fetal Estimado) / Peso ao Nascer) x 100. O erro do peso fetal estimado foi contrastado com o índice de massa corporal, diabetes e estado hipertensivo da gestação, utilizando-se o teste de Student. t e com idade gestacional e idade materna utilizando o índice de Pearson assumindo valores estatisticamente significativos menores que 0,05. Resultados: foram incluídos 258 pacientes. A margem de erro ultrassonográfica do PFE foi de 8,3% DP ± 7. Obteve-se valor de p para IMC de 0,228, diabetes p 0,915, estados hipertensivos p 0,967, dias em que foi realizada a ultrassonografia p 0,5 e idade gestacional p 0,001. Conclusões: A margem de erro ultrassonográfica do PFE está abaixo dos parâmetros internacionais. Foram encontradas associações estatisticamente significativas com a idade gestacional, mas não com as demais variáveis.

Association between dietary patterns and infant birth weight in brazilian pregnancy women with gestational diabetes: a cross-sectional study

Abstract Objective To evaluate the association between the dietary patterns (DPs) of pregnant women with GDM (gestational diabetes mellitus) and the birth weight (BW) of the infants. Methods Cross-sectional study with 187 adult pregnant women with GDM attended at a maternity in Rio de Janeiro from 2011 to 2014. Dietary intake was assessed in the third trimester using a semiquantitative food frequency questionnaire (FFQ). The outcomes were BW and weight adequacy for gestational age (GA). Reduced Rank Regression (RRR) was used to explain the following response variables: density of carbohydrates, fibres, and saturated fatty acids. Statistical analyzes included multinomial logistic regression models. Results The mean BW was 3261.9 (± 424.5) g. Three DPs were identified, with DP 3 (high consumption of refined carbohydrates, fast foods/snacks, whole milk, sugars/sweets, and soft drinks and low consumption of beans, vegetables, and low-fat milk and derivatives) being the main pattern, explaining 48.37% of the response variables. In the multinomial logistic regression analysis no statistically significant association was found between the tertiles of DPs and BW or the adequacy of weight for GA, even after adjustments of confounding covariates. Conclusion No significant associations were found between maternal DPs in the third trimester of pregnancy and infant BW or adequacy of weight for GA.

Exclusive breastfeeding and its association with pre- and postnatal factors: a cohort prospective study

Aim: This cohort study aimed to investigate the exclusive breastfeeding (EBF) prevalence and its association with maternal EBF intention and other variables. Method: Pregnant women (n=653) in the third trimester of pregnancy filled out a questionnaire on EBF intention using the Infant Feeding Intentions scale and other variables. After delivery, mothers were contacted by phone at the first (T1; n=467), third (T3; n=333), and sixth (T6; n=217) month of the baby's life or until breastfeeding was terminated, to collect data on breastfeeding, delivery, the newborn, oral habits, and family variables. The associations between independent variables and the outcomes (EBF prevalence at T1, T3, and T6) were analyzed by simple and multiple logistic regression models (α =0.05). Results: EBF prevalence was 81.2% at T1, 64.0% at T3, and 35.9% at T6. Nott use baby bottle (OR=612.59; OR=139.08; OR=15.05) and no pacifier use (OR=2.94; OR=2.78; OR=2.93) were associated with the outcome at T1, T3, and T6, respectively. Other associated variables were strong EBF intention (OR=1.71) at T1; higher birth weight (OR=1.62), childcare support (OR=2.59), maternal age (OR=0.54), being married or having a partner (OR=1.82) at T3; and not returning to work (OR=2.39) at T6. Conclusion: The EBF prevalence was high at the first month of the baby's life and decreased over six months. The EBF intention affected EBF initiation. Variables related to the mother´s demographic characteristics, the baby´s birth weight, the childcare support or the baby bottle/pacifier use were associated with EBF

Potenciales evocados auditivos de tronco en neonatos nacidos a gran altitud / Brainstem auditory evoked potentials in newborn infants born in a high-altitude area

Introducción. Una forma no invasiva y segura de evaluar los parámetros neurofisiológicos en recién nacidos es la evaluación de los potenciales evocados auditivos del tronco encefálico (PEAT). Objetivo. Evaluar las latencias e intervalos de ondas de los PEAT en neonatos sanos nacidos a gran altitud (Cusco, 3399 msnm). Población y métodos. Estudio transversal y prospectivo. Se incluyeron neonatos menores a 14 días de vida, dados de alta a menos de 7 días de nacidos, evaluados para determinar los valores de los PEAT a intensidades sonoras de 70 dB, 80 dB y 90 dB. Se incluyeron las variables edad gestacional, peso al nacer, tipo de parto. Se calcularon las diferencias de las medianas de las latencias e intervalos de las ondas según edad gestacional y peso al nacer. Resultados. Se evaluaron 96 neonatos (17 pretérminos). Las medianas de las latencias de las ondas I a V a 90 dB fueron las siguientes: onda I 1,56 ms; onda II 2,74 ms; onda III 4,37 ms; onda IV 5,62 ms, onda V 6,63 ms. La latencia de la onda I para 80 dB fue de 1,71 ms y para 70 dB de 1,88 ms. Los intervalos para las ondas (I-III), (III-V) y (I-V) fueron de 2,8 ms, 2,2 ms y 5,0 ms respectivamente, sin diferencias entre intensidades (p >0,05). La prematuridad y el bajo peso estuvieron asociados a latencias de la onda I más prolongadas (p <0,05). Conclusiones. Se presentan valores ajustados de latencias e intervalos de los PEAT en neonatos nacidos a gran altitud. Se identificó que, a distintas intensidades sonoras, se ven diferencias en las latencias de las ondas, pero no en los intervalos entre ondas.

Introduction. A non-invasive and safe way to assess neurophysiological parameters in newborn infants is the evaluation of brainstem auditory evoked potentials (BAEPs). Objective. To assess the latencies and wave intervals of BAEPs in healthy newborn infants born in a high-altitude area (Cusco, 3399 MASL). Population and methods. Cross-sectional and prospective study. Newborn infants younger than 14 days of age, discharged less than 7 days after birth, were assessed to determine BAEP values at intensities of 70 dB, 80 dB, and 90 dB. The study variables were gestational age, birth weight, and type of delivery. The median differences in wave latencies and intervals were estimated according to gestational age and birth weight. Results. A total of 96 newborn infants (17 preterm infants) were assessed. The median latencies of waves I­V at 90 dB were for wave I: 1.56 ms, wave II: 2,74 ms, wave III: 4.37 ms, wave IV: 5.62 ms, and wave V: 6.63 ms. The latency of wave I for 80 dB was 1.71 ms and for 70 dB, 1.88 ms. Wave intervals (I­III, III­V, I­V) were 2.8 ms, 2.2 ms, and 5.0 ms, respectively, without differences among intensities (p > 0.05). Prematurity and low birth weight were associated with a longer wave I latency (p < 0.05). Conclusions. Here we describe adjusted BAEP latency and interval values for newborn infants born at high altitude. At different sound intensities, we identified differences in wave latencies, but not in interwave intervals.

Establishment method and significance of birthweight curve and reference in single center / 中华妇产科杂志

Objective: To establish neonatal birthweight percentile curves based on single-center cohort database using different methods, compare them with the current national birthweight curves and discuss the appropriateness and significance of single-center birthweight standard. Methods: Based on a prospective first-trimester screening cohort at Nanjing Drum Tower Hospital from January 2017 to February 2022, the generalized additive models for location, scale and shape (GAMLSS) and semi-customized method were applied to generate local birthweight percentile curves (hereinafter referred to as the local GAMLSS curves, semi-customized curves) for 3 894 cases who were at low risk of small for gestation age (SGA) and large for gestation age (LGA). Infants were categorized as SGA (birth weight<10th centile) by both semi-customized and local GAMLSS curves, semi-customized curves only, or not SGA (met neither criteria). The incidence of adverse perinatal outcome between different groups was compared. The same method was used to compare the semi-customized curves with the Chinese national birthweight curves (established by GAMLSS method as well, hereinafter referred to as the national GAMLSS curves). Results: (1) Among the 7 044 live births, 404 (5.74%, 404/7 044), 774 (10.99%, 774/7 044) and 868 (12.32%, 868/7 044) cases were diagnosed as SGA according to the national GAMLSS curves, the local GAMLSS curves and the semi-customized curves respectively. The birth weight of the 10th percentile of the semi-customized curves was higher than that of the local GAMLSS curves and the national GAMLSS curves at all gestational age. (2) When comparing semi-customized curves and the local GAMLSS curves, the incidence of admission to neonatal intensive care unit (NICU) for more than 24 hours of infants identified as SGA by semi-customized curves only (94 cases) and both semi-customized and local GAMLSS curves (774 cases) was 10.64% (10/94) and 5.68% (44/774) respectively, both significantly higher than that in non SGA group [6 176 cases, 1.34% (83/6 176); P<0.001]. The incidence of preeclampsia, pregnancy<34 weeks, and pregnancy<37 weeks of infants identified as SGA by the semi-customized curves only and both semi-customized and local GAMLSS curves was 12.77% (12/94) and 9.43% (73/774), 9.57% (9/94) and 2.71% (21/774), 24.47% (23/94) and 7.24% (56/774) respectively, which were significantly higher than those of the non SGA group [4.37% (270/6 176), 0.83% (51/6 176), 4.23% (261/6 176); all P<0.001]. (3) When comparing semi-customized curves and the national GAMLSS curves, the incidence of admission to NICU for more than 24 hours of infants identified as SGA by semi-customized curves only (464 cases) and both semi-customized and national GAMLSS curves (404 cases) was 5.60% (26/464) and 6.93% (28/404) respectively, both significantly higher than that in non SGA group [6 176 cases, 1.34% (83/6 176); all P<0.001]. The incidence of emergency cesarean section or forceps delivery for non-reassuring fetal status (NRFS) in infants identified as SGA by semi-customized curves only and both semi-customized and national GAMLSS curves was 4.96% (23/464) and 12.38% (50/404), both significantly higher than that in the non SGA group [2.57% (159/6 176); all P<0.001]. The incidence of preeclampsia, pregnancy<34 weeks, and pregnancy<37 weeks in the semi-customized curves only group and both semi-customized and national GAMLSS curves group was 8.84% (41/464) and 10.89% (44/404), 4.31% (20/464) and 2.48% (10/404), 10.56% (49/464) and 7.43% (30/404) respectively, all significantly higher than those in the non SGA group [4.37% (270/6 176), 0.83% (51/6 176), 4.23% (261/6 176); all P<0.001]. Conclusion: Compared with the national GAMLSS birthweight curves and the local GAMLSS curves, the birth weight curves established by semi-customized method based on our single center database is in line with our center' SGA screening, which is helpful to identify and strengthen the management of high-risk infants.

Reference values and growth curves of length for weight and head circumference for weight among Chinese newborns / 中华儿科杂志

Objective: To establish the reference values and growth curves of length for weight and head circumference for weight among Chinese newborns in order to provide a reference for the assessment of body proportionality at birth. Methods: A cross-sectional design was applied. A total of 24 375 singleton live birth newborns with gestational ages at birth of 24+0 to 42+6 weeks were recruited from June 2015 to November 2018 from 13 cities including Beijing, Harbin, Xi'an, Shanghai, Nanjing, Wuhan, Guangzhou, Fuzhou, Kunming, Tianjin, Shenyang, Changsha, and Shenzhen, excluding those with maternal or newborn conditions that may impact the establishment of the reference values. The generalized additive model for location, scale, and shape was employed to establish reference values in terms of percentile and growth curves of length for weight and head circumference for weight for male and female newborns. The random forest machine learning method was employed to analyze the importance of variables between the established reference values in this study and the previous published weight/length, body mass index (BMI), ponderal index (PI), weight/head circumference, length/head circumference in the assessment of symmetrical and asymmetrical small for gestational age (SGA) newborns. Results: A total of 24 375 newborns with 13 197 male infants (preterm birth 7 042 infants and term birth 6 155 infants) and 11 178 female infants (preterm birth 5 222 infants and term birth 5 956 infants) were included in this study. The reference values in terms of percentile (P3, P10, P25, P50, P75, P90, P97) and growth curves of length for weight and head circumference for weight were obtained for male and female newborns with gestational ages of 24+0 to 42+6 weeks. The median birth lengths corresponding to the birth weights of 1 500, 2 500, 3 000, and 4 000 g were 40.4, 47.0, 49.3 and 52.1 cm for males and 40.4, 47.0, 49.2, and 51.8 cm for females, respectively; the median birth head circumferences were 28.4, 32.0, 33.2 and 35.2 cm for males and 28.4, 32.0, 33.1, and 35.1 cm for females, respectively. The differences of length for weight between males and females were minimum, with the difference range of -0.3 to 0.3 cm at P50; the differences of head circumference for weight between males and females were minimum, with the difference range of 0 to 0.2 cm at P50. Based on the match between birth length and birth weight for classifying symmetrical and asymmetrical SGA, length for weight and PI contributed the most, accounting for 0.32 and 0.25, respectively; based on the match between birth head circumference and birth weight, head circumference for weight and weight/head circumference contributed the most, accounting for 0.55 and 0.12, respectively; based on the match between birth length or head circumference with birth weight, head circumference for weight and length for weight contributed the most, accounting for 0.26 and 0.21, respectively. Conclusion: The establishment of the new standardized growth reference values and growth curves of length for weight and head circumference for weight among Chinese newborns are useful for clinical practice and scientific research.

Meta-analysis of the correlation between prenatal steroid exposure and hypoglycemia in late preterm neonates / 中华儿科杂志

Objective: To systematically evaluate the correlation between prenatal steroid exposure and hypoglycemia in late preterm neonates. Methods: Eight databases in either Chinese or English, including PubMed, the Cochrane Library, Embase, Medline, Scopus, CNKI, Wanfang and VIP, were searched to extract the studies on the correlation between prenatal steroid exposure and hypoglycemia in late preterm neonates published from the establishment of each database to December 2022. The Meta-analysis was performed using Stata 14.0 statistical software. Results: A total of 9 studies were included in this Meta-analysis, including 6 retrospective cohort studies, 2 prospective cohort studies and 1 randomized controlled trial (RCT) study, involving 9 143 premature infants. The Meta-analysis showed that prenatal steroid exposure increased the risk of late preterm neonatal hypoglycemia (RR=1.55, 95%CI 1.25-1.91, P<0.001). The similar correlation between prenatal steroid exposure and hypoglycemia in late preterm neonates was all found in the following subgroups: North America (RR=1.57, 95%CI 1.37-1.80, P<0.001), enrolling pregnant women with gestational diabetes (RR=1.62, 95%CI 1.26-2.08, P<0.001), A-grade literature quality (RR=1.43, 95%CI 1.14-1.79, P=0.002), criteria for hypoglycemia ≤40 mg/dl (1 mg/dl=0.056 mmol/L, RR=1.49, 95%CI 1.28-1.73, P<0.001), sample size of 501-1 500 (RR=1.69, 95%CI 1.19-2.40, P=0.003) and >1 500 (RR=1.65, 95%CI 1.48-1.83, P<0.001), steroid injection dosage and frequency of 12 mg 2 times (RR=1.66, 95%CI 1.50-1.84, P<0.001), the time interval from antenatal corticosteroid administration to delivery of 24-47 h (RR=1.98, 95%CI 1.26-3.10, P=0.003), unadjusted gestational age (RR=1.78, 95%CI 1.02-3.10,P=0.043) and unadjusted birth weight (RR=1.80, 95%CI 1.22-2.66, P=0.003). Meta-regression results showed that steroid injection frequency and dose were the main sources of high heterogeneity among studies (P=0.030). Conclusion: Prenatal steroid exposure may be a risk factor for hypoglycemia in late preterm neonates.

Correlation analysis between prenatal exposure of per-/polyfluoroalkyl compounds and neonatal outcome / 中华预防医学杂志

Objective: To investigate the correlation between the prenatal exposure of per-/polyfluoroalkyl substances (PFASs) and the neonatal outcome. Methods: A total of 506 maternal infant cohort samples were collected in Hangzhou, Zhejiang province from 2020 to 2021. The exposure levels of seven PFASs in maternal serum before delivery were detected by solid-phase extraction-ultra performance liquid chromatography tandem mass spectrometry. Multivariable linear regression model was used to analyze the influence of prenatal exposure of PFASs on birth weight, birth length and Apgar score. Results: The maternal age, prenatal body mass index and gestation age were (31.3±4.3) years old, (26.7±3.2) kg/m2 and (265.0±28.3) days, respectively. The birth weight, birth length and scores of Apgar-1 and Apgar-5 were (3.1±0.8) kg, (49.3±2.9) cm, (9.88±0.47) points and (9.99±0.13) points, respectively. PFASs were widely distributed in maternal serum, with the highest concentration of (18.453±19.557) ng/ml, (6.756±9.379) ng/ml and (5.057±8.555) ng/ml for perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS) and 6∶2 chlorinated polyfluorinated ether sulfonate (Cl-PFESA), respectively. Maternal age, parity and delivery mode were associated with the exposure level of PFASs (P<0.05). Subgroup analysis showed that PFOS had negative effects on birth weight (β=-0.958), birth length (β=-0.073) and Apgar-5 score (β=-0.288) for neonates in the low birth weight (LBW) group. 6∶2 Cl-PFESA and 8∶2 Cl-PFESA inhibited the birth weight (β=-0.926; β=-0.552) and length (β=-0.074; β=-0.045) of newborn in the LBW group. In addition, 4∶2 fluorotelomer sulfonate (FTS) was associated with increased birth weight (β=0.111) and decreased Apgar-5 score (β=-0.030) in the normal weight group. Conclusion: Prenatal exposure to PFASs is associated with birth weight, birth length and Apgar-5 score. It is necessary to continue to pay attention to the impact of PFASs on fetal growth and development through maternal-fetal transmission.

Status of fungal sepsis among preterm infants in 25 neonatal intensive care units of tertiary hospitals in China / 中华儿科杂志

Objective: To analyze the prevalence and the risk factors of fungal sepsis in 25 neonatal intensive care units (NICU) among preterm infants in China, and to provide a basis for preventive strategies of fungal sepsis. Methods: This was a second-analysis of the data from the "reduction of infection in neonatal intensive care units using the evidence-based practice for improving quality" study. The current status of fungal sepsis of the 24 731 preterm infants with the gestational age of <34+0 weeks, who were admitted to 25 participating NICU within 7 days of birth between May 2015 and April 2018 were retrospectively analyzed. These preterm infants were divided into the fungal sepsis group and the without fungal sepsis group according to whether they developed fungal sepsis to analyze the incidences and the microbiology of fungal sepsis. Chi-square test was used to compare the incidences of fungal sepsis in preterm infants with different gestational ages and birth weights and in different NICU. Multivariate Logistic regression analysis was used to study the outcomes of preterm infants with fungal sepsis, which were further compared with those of preterm infants without fungal sepsis. The 144 preterm infants in the fungal sepsis group were matched with 288 preterm infants in the non-fungal sepsis group by propensity score-matched method. Univariate and multivariate Logistic regression analysis were used to analyze the risk factors of fungal sepsis. Results: In all, 166 (0.7%) of the 24 731 preterm infants developed fungal sepsis, with the gestational age of (29.7±2.0) weeks and the birth weight of (1 300±293) g. The incidence of fungal sepsis increased with decreasing gestational age and birth weight (both P<0.001). The preterm infants with gestational age of <32 weeks accounted for 87.3% (145/166). The incidence of fungal sepsis was 1.0% (117/11 438) in very preterm infants and 2.0% (28/1 401) in extremely preterm infants, and was 1.3% (103/8 060) in very low birth weight infants and 1.7% (21/1 211) in extremely low birth weight infants, respectively. There was no fungal sepsis in 3 NICU, and the incidences in the other 22 NICU ranged from 0.7% (10/1 397) to 2.9% (21/724), with significant statistical difference (P<0.001). The pathogens were mainly Candida (150/166, 90.4%), including 59 cases of Candida albicans and 91 cases of non-Candida albicans, of which Candida parapsilosis was the most common (41 cases). Fungal sepsis was independently associated with increased risk of moderate to severe bronchopulmonary dysplasia (BPD) (adjusted OR 1.52, 95%CI 1.04-2.22, P=0.030) and severe retinopathy of prematurity (ROP) (adjusted OR 2.55, 95%CI 1.12-5.80, P=0.025). Previous broad spectrum antibiotics exposure (adjusted OR=2.50, 95%CI 1.50-4.17, P<0.001), prolonged use of central line (adjusted OR=1.05, 95%CI 1.03-1.08, P<0.001) and previous total parenteral nutrition (TPN) duration (adjusted OR=1.04, 95%CI 1.02-1.06, P<0.001) were all independently associated with increasing risk of fungal sepsis. Conclusions: Candida albicans and Candida parapsilosis are the main pathogens of fungal sepsis among preterm infants in Chinese NICU. Preterm infants with fungal sepsis are at increased risk of moderate to severe BPD and severe ROP. Previous broad spectrum antibiotics exposure, prolonged use of central line and prolonged duration of TPN will increase the risk of fungal sepsis. Ongoing initiatives are needed to reduce fungal sepsis based on these risk factors.

Management and prognosis of extremely preterm infants with gestational age ≤25+6 weeks / 中华儿科杂志

Objective: To investigate the outcomes including major complications and prognosis of extremely preterm infants with gestational age ≤25+6 weeks. Methods: The cross-sectional study enrolled 233 extremely preterm infants with gestational age ≤25+6 weeks who were admitted to the Department of Neonatology of Shenzhen Maternity and Child Healthcare Hospital from January 2015 to December 2021. The clinical data including perinatal factors, treatments, complications, and prognosis were extracted and analyzed. These extremely preterm infants were also grouped according to gestational age and year of admission to further analyze their survival rate, major complications, causes of death, and long-term outcomes. The comparisons between the groups were performed with Chi-square test and Kruskal-Wallis. Results: Among these 233 extremely preterm infants, 134 (57.5%) were males and 99 (42.5%) females. The gestational age was (24.6±0.9) weeks, the birth weight was 710.0 (605.0,784.5) g, and the overall survival rate was 61.8% (144/233). Among the surviving extremely preterm infants, the earliest gestational age was 22+2 weeks and the lowest birth weight was 390 g. There were 17.6% (41/233) of extremely preterm infants had treatment withdrawn and were discharged in line with the will of guardians. Among the rest 192 extremely preterm infants managed with aggressive treatments, 14 (7.3%) died in hospital and 34 (17.7%) had treatment withdrawn later due to severe complications. Of the 192 extremely preterm infants, 144 (75.0%) survived, and the survival rate increased year by year (χ2=26.28, P<0.001) while the mortality decreased year by year (χ2=14.09, P=0.027). Among the survivors, 20.8%(30/144) had no major complications, and the incidence of complications was also negatively related with the gestational age (χ2=7.24, P=0.044), and the length of invasive ventilation was negatively related to the gestational age (χ2=29.14, P<0.001). In the group of less than 23+6 weeks, all extremely preterm infants had one or more major complications. The follow-up were completed in 122 infants and revealed that delayed motor development, language retardation, and hearing and vision impairment accounted for 17.2% (21/122), 8.2% (10/122) and 17.2% (21/122), respectively. Conclusions: Extremely preterm infants with gestational age ≤25+6 weeks are difficult to treat, but the survival rate of infants undergoing aggressive treatments increases year by year. Although the prevalence of major complications is still high, most extremely preterm infants have acceptable prognosis during follow-up.

Dwelling time and complications of umbilical venous catheterization with different tip positions in preterm infants: a multicenter prospective cohort study / 中华儿科杂志

Objective: To compare the dwelling time and complications of low lying umbilical venous catheterization (UVC) in preterm infants with that of central UVC. Methods: This was a prospective cohort study. A total of 3 020 preterm infants from 44 neonatal intensive care units (NICU) who had UVC inserted from October 2019 to August 2021 were enrolled. Demographic and general baseline data, dwelling time of UVC and reasons for removal, complications and their occurrence time were collected. According to the position of the catheter tip, the preterm infants were divided into low lying UVC group (insertion depth of 3-5 cm) and central UVC group (the catheter tip was close to the entrance of right atrium, or at the 8th-9th thoracic vertebra level). The Mann-Whitney U test was used to compare the dwelling time and incidence of complications (cases/1 000 catheter days), and the independent t test and Chi-square test were used to compare the characteristics between the 2 groups. The receiver operating characteristic (ROC) curve was used to analyze the optimal cut-off value of UVC dwelling time. Results: Among the included 3 020 preterm infants, 1 624 (53.8%) were males, the gestational age was 29.9 (28.4, 31.6) weeks, the birth weight was (1 264±301) g, and 2 172 (71.9%) premature babies had central UVC. There were no significant differences in the proportion of males, the gestational age and the birth weight of neonates between the 2 groups (all P>0.05). There were also no significant differences in the rate of maternal history, PPROM>18 hours, chorioamnionitis, antenatal antibacterial angents exposure and antibacterial angents usage through UVC (all P>0.05). The dwelling time of central UVC was longer than that of low lying UVC (7 (6, 10) vs. 4 (3, 7) days, U=23.42, P<0.001). The complication incidence of central and low lying UVC were 20.0 and 70.8 cases/1 000 catheter days, respectively. The top 3 complications of central UVC were occlusion, catheter tip migration, and CLABSI (9.3, 3.5, 3.0 cases/1 000 catheter days). The top 3 complications of low lying UVC were catheter occlusion, CLABSI, and catheter tip migration (45.8, 6.3, 5.4 cases/1 000 catheter days). The ROC curve of UVC dwelling time and complications showed that the cut-off values ​​of central UVC and low lying UVC were 6.5 and 4.5 days, respectively. The 2 groups both showed a trend of increases in the 3 complications with the prolonged dwelling time. Cox regression analysis showed that the overall difference in the proportion of occlusion between the central UVC and low lying UVC groups was statistically significant (χ2=30.18, P=0.024). There were both no significant differences in catheter tip migration and CLABSI (both P>0.05). Conclusions: The most common UVC complication in preterm infants is occlusion. It is not recommended to keep a low lying UVC for longer than 4.5 days. During the whole dwelling period, a close monitoring for UVC complications is required.

Outcome of neonates born to mothers with chronic kidney disease / 中国当代儿科杂志

About 3% of pregnant women suffer from chronic kidney disease (CKD). This article reviews the literature on the outcomes of neonates born to mothers with CKD (including those undergoing dialysis and kidney transplantation), and the results show that CKD during pregnancy may increase the risk of preterm birth, low birth weight, and small for gestational age infant, but it does not increase the risk of congenital anomalies. As for long-term outcomes, CKD during pregnancy has no significant impact on offspring's physical development and immune function. Neurodevelopmental outcome of offspring is associated with preterm birth and low birth weight, rather than intrauterine drug exposure. However, further research and follow-up are needed to investigate the outcome of neonates born to mothers with CKD.

Association between early-life factors and pubertal timing in girls / 中国当代儿科杂志

OBJECTIVES@#To study the association between early-life factors (including birth weight, method of birth, gestational age, and history of gestational metabolic disorders) and pubertal timing in girls.@*METHODS@#The stratified cluster sampling method was used to select the girls in grades 2-3 and 7-8 from three primary schools and three middle schools in Guangzhou, China from March to December, 2019, and breast development was examined for all girls. A questionnaire survey was performed to collect the information on early-life factors. The multivariate logistic regression model was used to evaluate the association of gestational metabolic disorders, birth weight, method of birth, and gestational age with pubertal timing in girls. The Bootstrap method was used to assess the mediation effect of body mass index (BMI) (Z score) between high birth weight (≥4 000 g) and pubertal timing.@*RESULTS@#A total of 1 665 girls were enrolled, among whom 280 (16.82%) were judged to have early pubertal timing. The multivariate logistic regression analysis showed that high birth weight was associated with the increased risk of early pubertal timing (OR=2.12, 95%CI: 1.19-3.66, P=0.008). Nevertheless, no significant association was observed between other early-life factors and pubertal timing (P>0.05). The OR for the mediation effect of BMI (Z score) between high birth weight and early pubertal timing was 1.25 (95%CI: 1.09-1.47), accounting for 29.33% of the total effect of high birth weight on early pubertal timing.@*CONCLUSIONS@#High birth weight is associated with the increased risk of early pubertal timing in girls, and overweight/obesity may play a partial mediating role in the association between high birth weight and early pubertal timing in girls.

Changes and significance of type 2 innate lymphoid cells and their related factors in bronchopulmonary dysplasia / 中国当代儿科杂志

OBJECTIVES@#To investigate the changes and significance of type 2 innate lymphoid cells (ILC2), interleukin-33 (IL-33), interleukin-25 (IL-25), thymic stromal lymphopoietin (TSLP), interleukin-5 (IL-5), and interleukin-13 (IL-13) in peripheral blood of preterm infants with bronchopulmonary dysplasia (BPD).@*METHODS@#A total of 76 preterm infants with a gestational age of <32 weeks and a length of hospital stay of ≥14 days who were admitted to the Department of Pediatrics of the Affiliated Hospital of Jiangsu University from September 2020 to December 2021 were enrolled. According to the diagnostic criteria for BPD, they were divided into a BPD group with 30 infants and a non-BPD group with 46 infants. The two groups were compared in terms of the percentage of ILC2 and the levels of IL-33, IL-25, TSLP, IL-5, and IL-13 in peripheral blood on days 1, 7, and 14 after birth.@*RESULTS@#The BPD group had significantly lower birth weight and gestational age than the non-BPD group (P<0.05). On days 7 and 14 after birth, the BPD group had significantly higher levels of ILC2, IL-33, TSLP, and IL-5 than the non-BPD group (P<0.05), and these indices had an area under the curve of >0.7 in predicting the devolpment of BPD (P<0.05). Multivariate logistic regression analysis showed that after adjusting for gestational age and birth weight, peripheral blood IL-33, TSLP and IL-5 on days 7 and 14 after birth were closely related to the devolpment of BPD (P<0.05).@*CONCLUSIONS@#Early innate immune activation and upregulated expression of related factors may be observed in preterm infants with BPD. ILC2, IL-33, TSLP, and IL-5 may be used as biological indicators for early diagnosis of BPD.

The trend of birth weight of full-term newborns and its association with parental reproductive age in Chongqing municipality from 2010 to 2022 / 中华预防医学杂志

To analyze the trend of abnormal birth weight of full-term newborns and its correlation with parental reproductive age in Chongqing municipality from 2010 to 2022. Based on the Chongqing Birth Certificate System, full-term newborns born from January 2010 to December 2022 were selected. Parental information and birth weight were abstracted from the system. The joinpoint regression model was used to assess the trend of incidence of low birth weight (LBW) and macrosomia in the offspring from 2010 to 2022. The logistic regression model was utilized to analyze the association between parental reproduction age and birth weight of newborns. The average birth weight of 3 155 542 newborns was (3 305.8±410.5) g. The joinpoint regression model showed a decreasing trend for the incidence of LBW from 2010 to 2016 (APC=-4.26%, P<0.05), and an increasing trend from 2020 to 2022 (APC=8.99%, P<0.05). The incidence of macrosomia exhibited a decreasing trend from 2015 to 2022 (APC=-3.37%, P<0.05). The logistic regression model showed that, compared to the group with parents aged 20-34 years, the risk of LBW increased in other age groups. The risk of macrosomia decreased when either parent was aged<20 years, and increased when both parents were aged≥20 years. In conclusion, from 2010 to 2022, the incidence of LBW in full-term offspring in Chongqing municipality decreased first and then increased, and the incidence of macrosomia increased first and then decreased. Both young and advanced parental age were associated with an increased risk of LBW in offspring, and advanced parental age was also associated with an increased risk of macrosomia in offspring. Attention should be paid to the effects of advanced maternal and paternal age on offspring birth weight. Further efforts to control childbearing at a young age were needed.

Analysis of clinical effect and influencing factors of history-indicated cerclage or ultrasound-indicated cerclage in singleton pregnancy / 中华妇产科杂志

Objective: To investigate the clinical effect and the influencing factors of ultrasound-indicated cerclage and history-indicated cerclage in singleton gestation. Methods: The clinical data of 272 singleton pregnant women with cervical incompetence who underwent McDonald cervical cerclage due to medical history indication (history-indicated group) or ultrasound indication (ultrasound-indicated group) in Peking University First Hospital from January 2010 to February 2021 were retrospectively analyzed. The general clinical data and maternal and fetal outcomes were compared between the history-indicated group (141 cases) and ultrasound-indicated group (131 cases). According to the gestational age at delivery, 272 pregnant women who underwent cervical cerclage were further divided into ≥34 weeks group (225 cases) and <34 weeks group (47 cases), and the influencing factors of preterm birth before 34 weeks of gestation were analyzed. Results: (1) The median gestational age at cerclage was 16.6 weeks in the history-indicated group and 23.4 weeks in the ultrasound-indicated group, and the median gestational age extension at delivery was 21.4 weeks and 14.7 weeks, respectively, with statistically significant differences between the two groups (all P<0.05). (2) The full-term birth rate was 76.6% (108/141) in the history-indicated group and 71.0% (93/131) in the ultrasound-indicated group, the live birth rate was 97.2% (137/141) and 97.7% (128/131), and the median birth weight of live birth was 3 155 g and 3 055 g, respectively. The differences were not statistically significant (all P>0.05). Among 272 pregnant women with cervical cerclage, 265 neonates survived (97.4%, 265/272). The gestational age of 7 pregnant women who did not have live birth was ≤25 weeks of gestation (range: 19+1-25 weeks), and they were all clinically infected or confirmed chorioamnionitis or pathogenic microorganisms carrying during pregnancy, and their families gave up. The minimum birth weight of the surviving neonate was 850 g (gestational week of delivery was 26+6 weeks). (3) Univariate analysis showed that compared with ≥34 weeks group, the body mass index (BMI) of pregnant women in <34 weeks group was higher at 6-7 weeks of gestation (median: 24.5 vs 25.4 kg/m2), shorter cervical length (CL) at 1-2 weeks after surgery [(31.1±8.4) vs (26.1±11.0) mm], shorter CL at 26-28 weeks of gestation after surgery (median: 26.3 vs 16.0 mm), and higher incidence of elevated C-reactive protein (CRP) before and after surgery and before delivery. The differences were all statistically significant (all P<0.05). Multivariate logistic regression analysis showed that preterm birth before 34 weeks was negatively associated with CL at 26-28 weeks of gestation after cerclage (OR=0.902, 95%CI: 0.858-0.947; P<0.001), and was positively correlated with elevated CRP before delivery (OR=3.492, 95%CI: 1.652-7.381; P=0.001). There were no significant correlations between preterm birth and preoperative or postoperative CRP elevation, CL at 1-2 weeks after surgery, and BMI at 6-7 weeks of gestation (all P>0.05). Conclusions: Cervical cerclage for singleton pregnant women with cervical incompetence indicated by history or ultrasound both have good clinical efficacy, and there is no significant difference in maternal and fetal outcomes between the two groups. CL at 26-28 weeks of gestation and CRP before delivery are risk factors for preterm birth before 34 weeks of gestation after cervical cerclage.

Association between maternal plasma one-carbon biomarkers during pregnancy and fetal growth in twin pregnancies / 中华妇产科杂志

Objective: To characterize the relationship between the levels of plasma methyl donor and related metabolites (including choline, betaine, methionine, dimethylglycine and homocysteine) and fetal growth in twin pregnancies. Methods: A hospital-based cohort study was used to collect clinical data of 92 pregnant women with twin pregnancies and their fetuses who were admitted to Peking University Third Hospital from March 2017 to January 2018. Fasting blood was collected from the pregnant women with twin pregnancies (median gestational age: 18.9 weeks). The levels of methyl donors and related metabolites in plasma were quantitatively analyzed by high-performance liquid chromatography combined with mass spectrometry. The generalized estimation equation was used to analyze the relationship between maternal plasma methyl donors and related metabolites levels and neonatal outcomes of twins, and the generalized additive mixed model was used to analyze the relationship between maternal plasma methyl donors and related metabolites levels and fetal growth ultrasound indicators. Results: (1) General clinical data: of the 92 women with twin pregnancies, 66 cases (72%) were dichorionic diamniotic (DCDA) twin pregnancies, and 26 cases (28%) were monochorionic diamniotic (MCDA) twin pregnancies. The comparison of the levels of five plasma methyl donors and related metabolites in twin pregnancies with different basic characteristics showed that the median levels of plasma choline and betaine in pregnant women ≥35 years old were higher than those in pregnant women <35 years old, and the differences were statistically significant (all P<0.05). (2) Correlation between plasma methyl donor and related metabolites levels and neonatal growth indicators: after adjusting for confounding factors, plasma homocysteine level in pregnant women with twins was significantly negatively correlated with neonatal birth weight (β=-47.9, 95%CI:-94.3- -1.6; P=0.043). Elevated methionine level was significantly associated with decreased risks of small for gestational age infants (SGA; OR=0.5, 95%CI: 0.3-0.9; P=0.021) and low birth weight infants (OR=0.6, 95%CI: 0.4-0.9; P=0.020). Increased homocysteine level was associated with increased risks of SGA (OR=1.5, 95%CI: 1.0-2.2; P=0.029) and inconsistent growth in twin fetuses (OR=1.9, 95%CI: 1.0-3.7; P=0.049). (3) Correlation between the levels of plasma methyl donors and related metabolites and intrauterine growth indicators of twins pregnancies: for every 1 standard deviation increase in plasma choline level in pregnant women with twin pregnancies, fetal head circumference, abdominal circumference, femoral length and estimated fetal weight in the second trimester increased by 1.9 mm, 2.6 mm, 0.5 mm and 20.1 g, respectively, and biparietal diameter, abdominal circumference and estimated fetal weight increased by 0.7 mm, 3.0 mm and 38.4 g in the third trimester, respectively, and the differences were statistically significant (all P<0.05). (4) Relationship between plasma methyl donor and related metabolites levels in pregnant women with different chorionicity and neonatal birth weight and length: the negative correlation between plasma homocysteine level and neonatal birth weight was mainly found in DCDA twin pregnancy (β=-65.9, 95%CI:-110.6- -21.1; P=0.004). The levels of choline, betaine and dimethylglycine in plasma of MCDA twin pregnancy were significantly correlated with the birth weight and length of newborns (all P<0.05). Conclusion: Homocysteine level is associated with low birth weight in twins, methionine is associated with decreased risk of SGA, and choline is associated with fetal growth in the second and third trimesters of pregnancy.