Low birth weight (LBW) poses substantial health risks for neonates and can have enduring consequences, such as higher healthcare costs and adverse effects on human capital and productivity. However, comprehensive epidemiological data on LBW in Hainan Province, China’s Largest Free Trade Port and a strategically vital tropical region, remain strikingly limited. This study aims to assess the incidence of LBW in Hainan Free Trade Port and identify contributing risk factors. This population-based retrospective cohort study analyzed 1,538,023 live births in Hainan Province from 2010 to 2021. Data on neonatal and parental demographics, clinical factors, and socioeconomic indicators were systematically collected. LBW(i.e., 2499 g or below), very low birth weight(VLBW, < 1500 g), and extremely low birth weight (ELBW, < 1000 g) were classified based on birth weight. Spatial analysis used ArcGIS to assess geographic distribution. Temporal trends in LBW, VLBW, and ELBW incidence were analyzed using joinpoint regression, with segment-specific annual percentage changes (APC) and overall average annual percentage changes (AAPC) estimated over the full study period. Categorical variables were presented as frequencies and percentages, and between-group differences in the incidence of LBW were assessed using the χ² test.Multivariate binary logistic regression identified risk factors for LBW. The overall LBW incidence was 5.96

This study focuses on maternal antibody transfer following vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) before or during early pregnancy and its potential protective effects on infants, providing scientific evidence for vaccination strategies. This prospective study tested the samples for SARS-CoV-2 IgG antibody titers and neutralizing capacity and tracked the infections after birth. Perform multivariate analysis of factors influencing antibody transfer rate, newborn antibody titers, and infant infection. Total 87.1% (122/140) women received coronavirus disease 2019 (COVID-19) vaccine before or during early pregnancy, and 28 of them had breakthrough infection. The maternal and neonatal IgG positive rates at delivery were 60.7% (85/140) and 60.8% (87/143), respectively. A positive correlation was found between neonatal and maternal IgG antibody titers. Compared with the median IgG antibody transfer rate of infected pregnant women, that of vaccinated but not infected pregnant women was higher (1.21 versus: 1.53 [two doses], 1.71 [three doses]). However, neonatal IgG antibodies were relatively low (174.91 versus: 0.99 [two doses], 8.18 [three doses]), and their neutralizing capacity was weak. The overall effectiveness of maternal vaccination in preventing infant infection was 27.0%, and three doses had higher effectiveness than two doses (64.3% vs. 19.6%). Multivariate analysises showed that in vaccination group women receiving three doses or in infection group women with longer interval between infection and delivery had a higher antibody transfer rate and neonatal IgG antibody titer. More than half of women vaccinated before or during early pregnancy can achieve effective antibody transfer to newborns. However, the neonatal IgG antibody titer is low and has a weak neutralizing capacity, providing limited protection to infants.

Objective To assess the incidence, risk factors, and clinical characteristics of perinatal stroke in Beijing. Methods This multicenter prospective study included all the live births from 17 representative maternal delivery hospitals in Beijing from March 1, 2019 to February 29, 2020. Neonates with a stroke were assigned to the study group. Clinical data, including general information, clinical manifestations, and risk factors, were collected. Up until 18 months after birth, neonates were routinely assessed according to the Ages and Stages Questionnaire (ASQ) and/or the Bayley scale. Statistical analysis was done using the chi-squared, t-tests, and logistic regression analysis using SPSS version 26.0. Outcomes In total, 27 cases were identified and the incidence of perinatal stroke in Beijing was 1/2,660 live births, including 1/5,985 for ischemic stroke and 1/4,788 for hemorrhagic stroke. Seventeen cases (62.96%) of acute symptomatic stroke and convulsions within 72 h (10 cases, 37.04%) were the most common presentations. Ten patients showed no neurological symptoms and were found to have had a stroke through routine cranial ultrasonography after being hospitalized for non-neurological diseases. The risk factors include primiparity, placental or uterine abruption/acute chorioamnionitis, intrauterine distress, asphyxia, and severe infection. In the study group, 11.1% (3/27) of patients had adverse neurodevelopmental outcomes. The patients in the study group had lower scores for the ASQ than those in the control group in the communication, gross, and fine motor dimensions. Conclusion The incidence of perinatal stroke in Beijing was consistent with that in other countries. Routine neuroimaging of infants with risk factors may enable identification of asymptomatic strokes in more patients. Patients who have suffered from a stroke may have neurological sequelae; therefore, early detection, treatment, and regular follow-ups are beneficial for improving their recovery outcomes.

Background The cesarean section (CS) rate has risen globally during the last two decades. Effective and feasible strategies are needed to reduce it. The aim of this study was to assess the CS rate change after a two-stage intervention package that was designed to reduce the overall CS rate in Guangzhou, China. Methods and findings This intervention package was implemented by the Health Commission of Guangzhou Municipality in 2 stages (October 2010-September 2014 and October 2014-December 2016) and included programs for population health education, skills training for healthcare professionals, equipment and technical support for local healthcare facilities, and capacity building for the maternal near-miss care system. A retrospective repeated cross-sectional study was conducted to evaluate influences of the intervention on CS rates. A pre-intervention period from January 2008 to September 2010 served as the baseline. The primary outcome was the CS rate, and the secondary outcomes included maternal mortality ratio (MMR) and perinatal mortality rate (PMR), all obtained from the Guangzhou Perinatal Health Care and Delivery Surveillance System (GPHCDSS). The Cochran-Armitage test was used to examine the trends of the overall CS rate, MMR, and PMR across different stages. Segmented linear regression analysis was used to assess the change of the CS rate over the intervention period. A total of 1,921,932 records of births and 108 monthly CS rates from 2008 to 2016 were analyzed. The monthly CS rate declined across the intervention stages (Z = 75.067, p < 0.001), with an average rate of 42.4% at baseline, 39.8% at Stage 1, and 35.0% at Stage 2. The CS rate declined substantially among nulliparous women who delivered term singletons, with an accelerating decreasing trend observed across Stage 1 and Stage 2 (the difference in slopes: -0.09 [95% CI -0.16 to -0.02] between Stage 1 and baseline, p = 0.014; -0.11 [95% CI -0.20 to -0.02] between Stage 1 and Stage 2, p = 0.017). The CS rate in the remaining population increased during baseline and Stage 1 and subsequently decreased during Stage 2. The sensitivity analysis suggested no immediate impact of the universal two-child policy on the trend of the CS rate. The MMR (Z = -4.368, p < 0.001) and PMR (Z = -13.142, p < 0.001) declined by stage over the intervention period. One of the main limitations of the study is the lack of a parallel control group. Moreover, the influence of temporal changes in the study population on the CS rate was unknown. Given the observational nature of the present study, causality cannot be confirmed. Conclusions Apparent decline in the overall CS rate was observed in Guangzhou, China, after the implementation of a two-stage intervention package. The decline was most evident among nulliparous women who delivered term singletons. Despite some limitations for causal inference, Guangzhou's experience in controlling the CS rate by implementing composite interventions with public health education and perinatal healthcare service improvement could have implications for other similar areas with high rates of CS.

BACKGROUND In January 2016, a universal two-child policy was introduced in China. The association of interpregnancy interval (IPI) with perinatal outcomes has not previously been assessed among Chinese population. We investigated the effect of IPI after live birth on the risks of preterm delivery, and small, and large for gestational age births in China. METHODS We conducted a cohort study among 227 352 Chinese women with their first and second delivery during 2000 to 2015. IPI was calculated as months from first live delivery to conception of the second pregnancy. Poisson regression models with robust variance were fit to evaluate associations of IPI with risk of adverse perinatal outcomes, adjusted for potential confounders. RESULTS Compared to IPI of 24- <30 months, IPI <18 months was associated with higher risks of preterm birth (PTB) and small for gestational age (SGA). For IPI <6 months, the adjusted relative risks (RR) for PTB and SGA were 2.04 (95% confidence interval [CI] 1.83, 2.27) and 1.43 (95% CI 1.31, 1.57), respectively. Women with IPI ≥60 months had higher risks of PTB and large for gestational age (LGA). For IPI ≥120 months, the adjusted RRs for PTB and LGA were 1.67 (95% CI 1.43, 1.94) and 1.10 (95% CI 0.97, 1.26). CONCLUSIONS Women with IPI <18 months after live birth had higher risk of PTB and SGA, and IPI ≥60 months was associated with higher risk of PTB and LGA. These findings may provide information to Chinese couples about the appropriate interpregnancy interval for a second pregnancy.

BackgroundChildren as a population have high antimicrobial prescribing rates which may lead to high resistance of bacteria according to data from some single-center surveys of antibiotic prescribing rates in China. The acquirement of baseline data of antibiotic prescribing is the basis of developing intervention strategies on inappropriate antimicrobial prescriptions. Few studies show clearly the pattern and detailed information on classes of antibiotics and distribution of indications of antibiotic prescriptions in children in China. This study aims to assess the antibiotic prescribing patterns among children and neonates hospitalized in 18 hospitals in China.MethodsA 24-hour point prevalence survey on antimicrobial prescribing was conducted in hospitalized neonates and children in China from December 1st, 2016 to February 28th, 2017. Information on the antibiotic use of patients under 18years of age who were administered one or more on-going antibiotics in the selected wards over a 24-hour period was collected. These data were submitted to the GARPEC (Global Antimicrobial Resistance, Prescribing and Efficacy in Children and Neonates) web-based application (https://pidrg-database.sgul.ac.uk/redcap/). For statistical analysis, Microsoft Excel 2007 and SPSS 22.0 were used.ResultsThe antibiotic data were collected in 35 wards in 18 hospitals from 9 provinces. In total, 67.76% (975/1439) of the patients (n=1439) were given at least one antibiotic, including 58.1% (173/298) of neonates (n=298) and 70.3% (802/1141) of children (n=1141). In neonates, the three most frequently prescribed antibiotics were third-generation cephalosporins (41.7%), penicillins plus enzyme inhibitor (23.8%), and carbapenems (11.2%). In children, the three most frequently prescribed antibiotics were third-generation cephalosporins (35.5%), macrolides (23.2%), and penicillins plus enzyme inhibitors (15.9%). The most common indication for antibiotics was proven or probable bacterial lower respiratory tract infection (30.9% in neonates and 66.6% in children).ConclusionsAntibiotics are commonly prescribed in the Chinese children population. It is likely that the third-generation cephalosporins and macrolides are currently overused in Chinese children. Efforts must be made to ensure safe and appropriate antibiotic prescribing to reduce and prevent the future development of antibiotic resistance.

In 2015, a universal two-child policy was released in China, which give new opportunity to millions of couples to have a second child. There is lack of data that assessed the effect of interpregnancy interval (IPI) on perinatal outcomes in a Chinese population. We investigated the effects of IPI on adverse birth outcomes in China. We conducted a retrospective cohort study of 227 352 Chinese women with their first and second delivery between 2000 and 2015. We assessed the relation between the IPI, defined as the time in months between the first delivery date and date of conception of the second pregnancy and preterm birth (PTB) (delivery < 37 weeks), being large for gestational age (LGA) (birth weight > 90th %) and being small for gestational age (SGA) (birth weight <10th %). Propensity score weights were used to balance the distributions of covariates across different IPI groups. We found a J-shape association between the IPI and risk of PTB, and approximate linear associations for LGA and SGA (Figure 1). Compared to women with IPIs of 24-29 months, those with IPIs of <6, 6-11, and 12-17 months had higher risks of PTB and SGA. Women with IPIs of 60-119 months had higher risks of PTB (adjusted odds ratio [aOR] 1.23, 95% confidence interval [CI] 1.08-1.41) and LGA (aOR 1.23, 95% CI 1.12-1.35). Effects of long IPIs (≥120 months) on PTB (adjusted OR 1.52, 95% CI 0.64-3.62) and LGA (aOR 1.80, 95% CI 0.89-3.64) were attenuated after propensity score adjustment (Table 2). In this large study from China, we found that IPIs <18 were associated with increased risk of PTB and SGA, whereas IPIs ≥60 months were associated with higher risk of PTB and LGA. Our findings may help health authorities and pregnancy care providers in China and elsewhere in the world to devise appropriable plans for a second pregnancy, including the predicted increase of second child births.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

BACKGROUND: Although effects of weather changes on human health have been widely reported, there is limited information regarding effects on pregnant women in developing countries.OBJECTIVE: We investigated the association between maternal exposure to ambient temperature and the risk of preterm birth (< 37 weeks of gestation) in Guangzhou, China.METHODS: We used a Cox proportional hazards model to estimate associations between preterm birth and average temperature during each week of gestation, with weekly temperature modeled as a time-varying exposure during four time windows: 1 week (the last week of the pregnancy), 4 weeks (the last 4 weeks of the pregnancy), late pregnancy (gestational week 20 onward), and the entire pregnancy. Information on singleton vaginal birth between 2001 and 2011 was collected. Daily meteorological data during the same period were obtained from the Guangzhou Meteorological Bureau.RESULTS: A total of 838,146 singleton vaginal births were included, among which 47,209 (5.6%) were preterm births. High mean temperatures during the 4 weeks, late pregnancy, and the entire pregnancy time windows were associated with an increased risk of preterm birth. Compared with the median temperature (24.4 degrees C), weekly exposures during the last 4 weeks of the pregnancy to extreme cold (7.6 degrees C, the 1st percentile) and extreme heat (31.9 degrees C, the 99th percentile) were associated with 17.9% (95% CI: 10.2, 26.2%) and 10.0% (95% CI: 2.9, 17.6%) increased risks of preterm birth, respectively. The association between extreme heat and preterm birth was stronger for preterm births during weeks 20-31 and 32-34 than those during weeks 35-36.CONCLUSIONS: These findings might have important implications in preventing preterm birth in Guangzhou as well as other areas with similar weather conditions.

目的 寻找适合于构建人体测量指标生长标准曲线的方法和途径.方法 以构建广州市胎龄别新生儿出生体重百分位曲线为例,从Tukey方法、稳健性回归和高斯混合模型等三种异常数据识别和剔除方法中获得最佳数据预处理效果,然后对比三次样条方法、LMS方法和GAMLSS方法对百分位数曲线构建的影响.结果 高斯混合模型对多峰分布数据中的主要分布识别比较理想,而对单峰分布,稳健性回归比Tukey方法更加可靠.而从拟合优度以及小于胎龄儿(SGA)、大于胎龄儿(LGA)的识别能力看,GAMLSS构建的胎龄别新生儿出生体重百分位曲线比三次样条和LMS方法估计精度更高.结论 数据预处理过程应根据数据分布的特点选用合适的异常值识别和剔除方法,而曲线光滑过程中,GAMLSS方法可以对四阶矩进行建模,得到的百分位数曲线平滑且误差更小.

Objective To formulate a new birthweight reference for different gestational ages in Guangzhou, southern China, and compare it with the currently used reference in China and the global reference.Design and setting All singleton live births of more than 26 weeks' gestational age recorded in the Guangzhou Perinatal Health Care and Delivery Surveillance System for the years 2009, 2010 and 2011 (n=510 837) were retrospectively included in the study. In addition, the study sample was supplemented by all singleton live births (n=3538) at gestational ages 26-33 weeks from 2007 and 2008. We used Gaussian mixture models and robust regression to exclude outliers of birth weight and then applied Generalized Additive Models for Location, Scale, and Shape (GAMLSS) to generate smoothed percentile curves separately for gender and parity.Results Of infants defined as small for gestational age (SGA) in the new reference, 15.3-47.7% (depending on gestational age) were considered appropriate for gestational age (AGA) by the currently used reference of China. Of the infants defined as SGA by the new reference, 9.2% with gestational ages 34-36 weeks and 14.3% with 37-41 weeks were considered AGA by the global reference. At the 50th centile line, the new reference curve was similar to that of the global reference for gestational ages 26-33 weeks and above the global reference for 34-40 weeks.Conclusions The new birthweight reference based on birthweight data for neonates in Guangzhou, China, differs from the reference currently used in China and the global reference, and appears to be more relevant to the local population.

Background Recent surveillance data suggest that mean birth weight has begun to decline in several developed countries. The aim of this study is to examine the changes in birth weight among singleton live births from 2002 to 2012 in Guangzhou, one of the most rapidly developed cities in China. Methods We used data from the Guangzhou Perinatal Health Care and Delivery Surveillance System for 34108 and 54575 singleton live births with 28–41 weeks of gestation, who were born to local mothers, in 2002 and 2012, respectively. The trends in birth weight, small (SGA) and large (LGA) for gestational age and gestational length were explored in the overall population and gestational age subgroups. Results The mean birth weight decreased from 3162 g in 2002 to 3137 g in 2012 (crude mean difference, −25 g; 95% CI, −30 to −19). The adjusted change in mean birth weight appeared to be slight (−6 g from 2002 to 2012) after controlling for maternal age, gestational age, educational level, parity, newborn's gender and delivery mode. The percentages of SGA and LGA in 2012 were 0.6% and 1.5% lower than those in 2002, respectively. The mean gestational age dropped from 39.2 weeks in 2002 to 38.9 weeks in 2012. In the stratified analysis, we observed the changes in birth weight differed among gestational age groups. The mean birth weight decreased among very preterm births (28–31 weeks), while remained relatively stable among other gestational age subcategories. Conclusions Among local population in Guangzhou from 2002 to 2012, birth weight appeared to slightly decrease. The percentage of SGA and LGA also simultaneously dropped, indicating that newborns might gain a healthier weight for gestational age.

Objective: This study aimed to determine the impact of maternal cervical incompetence (with or without McDonald cerclage) on mortality and morbidity of preterm infant with birth weight <2000g. Methods: 581 neonates were eligible for this study, 79 with cervical incompetence and 502 without it (control). Incidences of neonatal respiratory distress syndrome (RDS), bronchopulmonary dysplasia (BPD), intraventricular hemorrhage (IVH), neonatal necrotizing enterocolitis (NEC), retinopathy of prematurity (ROP), periventricular leukomalacia (PVL), severe asphyxia, small for gestational age (SGA), early-onset sepsis (EOS), and mortality were compared between the two groups. Findings: Mean gestational age was earlier in cervical incompetence group than in control (30.2±2.1 vs 30.7±1.9, P<0.05). Except lower frequency of SGA, there were no significant differences in the incidences of RDS, BPD, ROP, PVL, IVH, NEC, EOS, severe asphyxia and mortality between the two groups. Infants with no cerclage had a higher prevalence of RDS (21/66 vs 9/13, P<0.05) compared to cerclage group due to lower mean gestational age (30.68±2.1 vs 28.6±1.4, P<0.01) and birth weight (1519.5±274.6 vs 1205.8±204.4, P<0.001), and clinical neonatal outcomes of the elective cerclage were similar to emergency cerclage in cervical incompetence groups. Conclusion: Maternal cervical incompetence was not associated with postnatal adverse neonatal outcomes. Lower mean gestational age was a major risk associated with higher prevalence of RDS in preterm neonates with no McDonald cerclage, and emergency cerclage did not predict poor clinical neonatal outcomes.

Background: Listeria monocytogenes infection is not commonly reported in China. Increasing the awareness of neonatal listeriosis is necessary. Methods: Six cases of neonatal listeriosis were diagnosed in the neonatal intensive care unit at Beijing Obstetrics & Gynecology Hospital in 2008. We reviewed the clinical features, laboratory findings, timing of treatment, medications used, and the history of the mothers during pregnancy. Results: All six cases were preterm infants. Blood cultures were positive for L. monocytogenes . All of the mothers developed fever in the third trimester of pregnancy, and three of them ended their pregnancy the day the fever appeared. The severity of the clinical symptoms varied in each infant, and all cases were treated with antibiotics immediately after birth. All six cases were discharged from hospital in good health. Conclusions: Neonatal Listeria infection is generally a severe disease. Pregnant women must guard against fever and other manifestations, such as Listeria infection. Clinicians encountering such cases should be attentive to the patient's condition and should provide appropriate antibiotic treatment. Early detection and effective targeted treatment of listeriosis helps to improve the patient's survival and prognosis.