Preterm births in China between 2012 and 2018: an observational study of more than 9 million women

The correlation between serum total bile acid and adverse perinatal outcomes in pregnant women with intrahepatic cholestasis of pregnancy (ICP) and non-ICP hypercholanemia of pregnancy

BACKGROUND

The association between excessive serum total bile acid (TBA) and adverse perinatal outcomes in individuals with non-intrahepatic cholestasis of pregnancy (non-ICP) hypercholanemia has not been determined, and it is unclear if this link is similar to that observed in patients with ICP.

OBJECTIVE

To examine the adverse perinatal outcomes in two specific subcategories: those with ICP and those with non-ICP, including individuals with liver disease and asymptomatic hypercholanemia of pregnancy (AHP), at different levels of TBA. Investigate the correlation between TBA levels and adverse perinatal outcomes of ICP, liver disease, and AHP.

METHODS

From 2013 to 2021, pregnant women with excessive TBA levels were taken from the electronic medical record database of our hospital and categorized into three groups: ICP (n = 160), liver disease (n = 164), and AHP (n = 650). This was done as part of a retrospective cohort research project. Multivariable regression and subgroup analyses were performed to examine the association between TBA levels and adverse perinatal outcomes in each group.

RESULTS

The study found no significant differences in adverse perinatal outcomes between the ICP and liver disease groups at different TBA levels. However, at moderate TBA levels, both groups had a higher risk of adverse perinatal outcomes than the AHP group (p < 0.017). Among liver disease cases with TBA ≥ 100µmol/L, three cases of perinatal deaths (6.67%) associated with moderate-to-severe acute hepatitis occurred between 27 and 33 weeks of gestation. A 59% higher chance of perinatal death was found for every 10 µmol/L rise in TBA, even after significant variables and confounders were taken into account (adjusted odds ratio (aOR) = 1.59; 95% confidence interval (CI): 1.06-2.40; p = 0.03).

CONCLUSIONS

If a pregnant woman has moderate-to-severe liver disease and TBA ≥ 100µmol/L, preterm termination of pregnancy (before 34 weeks) may be considered.

A prospective multicenter birth cohort in China: pregnancy health atlas

The China Prospective Multi-Center Birth Cohort Study was launched in 2022. In collaboration with medical centers in 12 cities, it aims to establish a high-quality, multidimensional cohort comprising 20,000 natural pregnancy and assisted reproductive families. As of June 26, 2024, 12,911 pregnant women have participated in this study, and 161,122 biological samples have been collected. These samples cover four critical periods (early pregnancy, mid-pregnancy, late pregnancy, and postpartum) and comprise 10 different types such as serum, plasma, and urine. The study has collected comprehensive information from early pregnancy to newborns. The participants have an average age of 29.76 years, an average height of 160.46 cm, an average pre-pregnancy BMI of 23.11, and an average BMI of 27.25 before delivery. The cohort includes individuals from 26 ethnic groups, with 25 minority groups comprising 5.03% of the population. Guizhou Province exhibits the highest percentage of ethnic minorities at 24.96% and Guangdong Province owns the highest proportion (12.22%) of women with two or more children. The prevalence of thalassemia in Guangdong Province is seven times higher than in other provinces. Among pregnant women over 35 years old, the prevalence of gestational diabetes mellitus is twice that of women under 35. Additionally, the prevalence of preeclampsia in women with assisted reproductive pregnancies is more than twice that of those with natural pregnancies. The study extensively collected diverse data and biological samples, making this cohort an ideal candidate for DOHaD field and multi-omics research.

Analysis of the relationship between the quality of antenatal care examinations and the incidence of preterm birth and low birth weight

BACKGROUND

Antenatal care (ANC) plays a crucial role in ensuring maternal and child safety and reducing adverse delivery outcomes. This study aimed to analyze the association between the quality of ANC and the occurrence of preterm birth and low birth weight in a sample of the population from 16 regions in 8 provinces in China.

METHODS

Data from all closed cases of pregnant women and newborns reported in the Maternal and Child Health Monitoring System from January 1, 2018, to December 31, 2018, in 16 monitoring regions across 8 provinces in China were collected and included in the analysis, resulting in a total of 49,084 pregnant women and 49,026 newborns.

RESULTS

The mean number of ANC visits was 6.95 ± 3.45. By percentage, 78.79% of the women received ANC examinations at least five times. The percentage of normative ANC examinations and the percentage of qualified ANC examinations was 30.98% and 8.0% respectively. The gestational age(χ2 = 229.305, p<0.001), birth weight (χ2 = 171.990, p<0.001) and the occurrence of neonatal complications (χ2 = 53.112, p<0.001) were all significantly related to the number of ANC visits to mothers. There was a correlation between gestational age (χ2 = 1021.362, p<0.001;χ2 = 194.931, p<0.001) and birth weight (χ2 = 259.009, p<0.001; χ2 = 70.042, p<0.001) with normative ANC and qualified ANC examinations. As the number of ANC examinations increased, the rates of preterm birth and low birth weight decreased. Pregnant women who did not receive normative ANC examinations had a higher risk of preterm birth and neonatal low birth weight compared to those who did; Adjusted Odds Ratio (95%CI) was 23.33(16.97~32.07)and 1.61(1.37~1.90) respectively. Pregnant women who did not receive qualified ANC examinations had a higher risk of preterm birth and neonatal low birth weight compared to those who did; Adjusted Odds Ratio (95%CI) was 15.05(8.45~26.79)and 1.36 (1.02~1.82) respectively.

CONCLUSION

The percentage of women who received normative ANC examination and qualified ANC examination is still low in China, and the quality of antenatal care significantly affects the occurrence of preterm birth and low birth weight in newborns.

[Effects of antenatal corticosteroids on outcomes of very premature infants and neurodevelopment during infancy]

OBJECTIVES

To explore the effects of antenatal corticosteroids (ACS) on the outcomes of very premature infants (VPIs) and neurodevelopment during infancy.

METHODS

A retrospective study was conducted on 190 VPIs admitted to the Department of Pediatrics of the First Affiliated Hospital of Anhui Medical University from January 2020 to December 2022. The infants were categorized into four groups based on ACS usage and dosage: no ACS group (n=18), single-course group (n=88), multi-course group (n=40), and partial-course group (n=44). The clinical outcomes, Neonatal Behavioral and Neurological Assessment (NBNA) scores at 40 weeks of corrected age, and Gesell Developmental Schedule (Gesell) scores at 1 year of corrected age were compared among the four groups. The impact of timing of ACS use on the Gesell scores of infants at 1 year of corrected age in VPIs with specific gestational ages was analyzed.

RESULTS

The incidence rates of neonatal respiratory distress syndrome, bronchopulmonary dysplasia, transient tachypnea of the newborn, and neonatal pneumonia were significantly lower in the partial-course, single-course, and multiple-course groups compared with the no ACS group (P<0.008). However, there was no significant difference among the partial-course, single-course, and multiple-course groups (P>0.008). The NBNA scores (behavioral ability, active muscle tone, primitive reflexes, and general assessment) at 40 weeks of corrected age were significantly higher in the no ACS, partial-course, and single-course groups than in the multiple-course group (P<0.008). The proportion of VPIs with normal neurodevelopment at 1 year of corrected age was significantly higher in the no ACS, partial-course, and single-course groups than in the multiple-course group (P<0.008). The timing of ACS use had no significant effect on neurodevelopment at a corrected age of 1 year in infants with various gestational ages (P>0.05).

CONCLUSIONS

ACS is crucial for the development of the respiratory system in VPIs, but multiple courses of ACS may cause neurodevelopmental abnormalities. The impact of ACS use on neurodevelopment is independent of gestational age and the timing of ACS use.

Secular variation and risk factors of preterm birth in Hainan, the Free Trade Port in China from 2010 to 2021

OBJECTIVES

Preterm delivery rates have increased obviously worldwide over the past decade, yet reliable epidemiological studies on the incidence of preterm birth and temporal trends are not available in Hainan, The Free Trade Port in China. We aimed to describe the rate of preterm birth and trends between 2010 and 2021 and to primarily explore risk factors associated with preterm birth in Hainan, China.

METHODS

This was an observational study was based on data from the Hainan Provincial Birth Certificate System (HPBCS) for live births between 1 January 2010 and 31 December 2021. We included pregnancies resulting in at least one live birth, with newborns born at a gestational age of 28 weeks or greater, or with a birth weight of 1000 g or more. The outcome were preterm birth rates and their trends over time. Potential risk factors were collected, including infant gender, maternal age, paternal age, maternal ethnicity, paternal ethnicity, home address, and single or multiple pregnancies. The logistic regression model was used to assess the relationship between preterm birth and potential risk factors.

RESULTS

A total of 1,537,239 live births and 86,328 preterm births were investigated, giving a total preterm birth rate of 5.62%. The overall preterm birth rate increased from 4.47% in 2010 to 7.12% in 2021 (compound annual growth rate [CAGR] 4.32). The CAGR of late preterm birth is consistent with the overall preterm birth rate (4.32%). The fastest growth is observed in the rate of very preterm births (5.53%), while the rate of moderate preterm births exhibits the slowest growth (3.87%). Infant gender, multiple pregnancy, home address, parental age, and ethnicity had significant effects on preterm birth.

CONCLUSION

The preterm birth rate was increasing year by year from 2010 to 2021 in Hainan, The Free Trade Port in China. Incidence of preterm births in Hainan Province in relation to multiple pregnancies, infant sex, parental age, parental race and residential address.

Expected 8-Week Prenatal vs 12-Week Perinatal Tenofovir Alafenamide Prophylaxis to Prevent Mother-to-Child Transmission of Hepatitis B Virus: A Multicenter, Prospective, Open-Label, Randomized Controlled Trial

INTRODUCTION

The course of maternal antiviral prophylaxis to prevent mother-to-child transmission of hepatitis B virus (HBV-MTCT) varies greatly, and it has not been demonstrated in a randomized controlled study.

METHODS

In this multicenter, open-label, randomized controlled trial, eligible pregnant women with HBV DNA of 5.3-9.0 log 10 IU/mL who received tenofovir alafenamide fumarate (TAF) from the first day of 33 gestational weeks to delivery (expected 8 week) or to 4 weeks postpartum (expected 12 week) were randomly enrolled at a 1:1 ratio and followed until 6 months postpartum. All infants received standard immunoprophylaxis (hepatitis B immunoglobulin and vaccine). The primary end point was the safety of mothers and infants. The secondary end point was the HBV-MTCT rate of infants at the age of 7 months.

RESULTS

Among 119 and 120 intention-to-treat pregnant women, 115 and 116 women were followed until delivery, and 110 and 112 per-protocol mother-infant dyads in 2 groups completed the study. Overall, TAF was well tolerated, no one discontinued the therapy due to adverse events (0/239, 0%, 95% confidence interval [CI] 0%-1.6%), and no infant had congenital defects or malformations at delivery (0/231, 0%, 95% CI 0%-1.6%). The infants' physical development at birth (n = 231) and at 7 months (n = 222) was normal. Furthermore, 97.0% (224/231, 95% CI 93.9%-98.5%) of women achieved HBV DNA <5.3 log 10 IU/mL at delivery. The intention-to-treat and per-protocol infants' HBV-MTCT rates were 7.1% (17/239, 95% CI 4.5%-11.1%) and 0% (0/222, 95% CI 0%-1.7%) at the age of 7 months. Comparatively, 15.1% (18/119, 95% CI 9.8%-22.7%) vs 18.3% (22/120, 95% CI 12.4%-26.2%) of women in the 2 groups had mildly elevated alanine aminotransferase levels at 3 months and 6 months postpartum, respectively ( P = 0.507); notably, no one experienced alanine aminotransferase flare (0% [0/119, 95% CI 0%-3.1%] vs 0% [0/120, 0%-3.1%]).

DISCUSSION

Maternal TAF prophylaxis to prevent HBV-MTCT is generally safe and effective, and expected 8-week prenatal duration is feasible. ClinicalTrials.gov , NCT04850950.

Delivery room resuscitation and short-term outcomes in very preterm infants: a multicenter cross-sectional study in China

Objective

To explore the risk factors of delivery room (DR) resuscitation and assess the association of DR resuscitation with neonatal outcomes in very preterm infants (VPIs).

Methods

A multicenter retrospective cross-sectional study included VPIs with gestational age (GA) <32 weeks born between January, 2022 and June, 2023 and admitted to neonatal intensive care units of six tertiary hospitals in Shenzhen within 24 h after birth. They were divided into routine care group, positive-pressure ventilation (PPV) group, and endotracheal intubation (ETT) group based on the highest intensity of resuscitation received at birth. The association of antepartum and intrapartum risk factors and short-term outcomes with the intensity of DR resuscitation was evaluated.

Results

Of 683 infants included in this study, 170 (24.9%) received routine care, 260 (38.1%) received bag and mask ventilation or T-piece ventilation and 253 (37%) received ETT. Among the antepartum and intrapartum factors, exposure to antenatal steroids (ANS) decreased the likelihood of ETT. Increasing GA decreased the likelihood of receiving a higher level of DR resuscitation. Among the neonatal outcomes, increasing intensity of DR resuscitation was associated with a raise in the risk of Bronchopulmonary dysplasia. Higher levels of DR resuscitation were associated with the risk of early-onset sepsis. ETT was significantly associated with an increased risk of death.

Conclusion

Among VPIs, low GA and no ANS use increased the risk of high-intensity DR resuscitation interventions; and those who receiving ETT were associated with an increased risk of adverse clinical outcomes.

Global, regional, and national burden of preterm birth, 1990-2021: a systematic analysis from the global burden of disease study 2021

Background

Preterm birth and its complications are leading causes of mortality among children under five years of age. Given the increasing burden of preterm birth on neonatal mortality and long-term health outcomes worldwide, a comprehensive global analysis is essential to guide effective public health interventions and policies. This study aims to assess the burden of preterm birth at the global, regional, and national levels.

Methods

Using data from the Global Burden of Disease (GBD) 2021 database, this study analysed trends in age-standardized incidence rates (ASIR), age-standardized mortality rates (ASMR), and disability-adjusted life-years (DALYs) as primary outcomes for preterm birth from 1990 to 2021 at global, regional, and national levels. Data were assessed using joinpoint regression analysis, decomposition analysis, and the health inequality concentration index.

Findings

Globally, the incidence, mortality and DALYs due to preterm birth have shown a declining trend, but ASIR started to increase in 2016. Males were more commonly born preterm than females (12329075.82, 95% uncertainty interval [UI]: 12192632.55-12464605.4 vs. 9224694.94, 95% UI: 9113876.1-9330107.89). Changes in DALYs were primarily due to epidemiological change (111.97%) and population (-21.59%). Low Socio-demographic Index (SDI) regions increased in annual incidence cases (43.1%, 95% UI: 40.17-46.09), while high SDI regions decreased in annual incidence cases (-9.6%, 95% UI: -11.45 to -7.79). The highest annual mortality and DALYs respectively occurred in sub-Saharan Africa (295490.66, 95% UI: 241762.78-353624.41) and South Asia (32760273.93, 95% UI: 27295547.76-39070225.69). Western sub-Saharan Africa showed the largest increase in annual incidence (98.95%, 95% UI: 94.77 to 103.09), and Australasia had the lowest annual mortality (287.18, 95% UI: 244.26-339.42) and DALYs (61081.4, 95% UI: 50897.33-73069.96). Western sub-Saharan Africa also had the highest ASMR (21.57, 95% confidence interval [CI]: 17.9-25.89). The highest ASIR (543.78, 95% CI: 535.11-553.21) and age-standardized DALYs (2064.65, 95% CI: 1717.27-2473.36) both occurred in South Asia, while the lowest ASIR and age-standardized DALYs were seen in East Asia (147.31, 95% CI: 144.22-150.85) and High-income Asia Pacific (143.32, 95% CI: 117.9-167.25). India, Nigeria, and Pakistan ranked highest globally in terms of annual incidence cases, mortality, and DALYs, while the lowest annual incidence, mortality and DALYs respectively occurred in Tokelau (2.34, 95% UI: 2.12-2.56), San Marino (0.04, 95% UI: 0.02-0.07) and Tokelau (17.22, 95% UI: 11.11-24.95).

Interpretation

While the global burden of preterm birth has decreased, significant disparities persist, especially in low SDI regions. There is a need for more refined policies and preventive measures to effectively address preterm birth.

Funding

No funds, grants, or other support was received.

Strategic Implementation of Fragile X Carrier Screening in China: A Focused Pilot Study

Fragile X syndrome is the leading genetic cause of intellectual disability and autism spectrum disorders. Female premutation carriers exhibit no obvious symptoms during reproductive age, but the premutation allele can expand to full mutation when transmitted to the fetus. Given the relatively low prevalence but large population, the distinct health care system, the middle-income economic status, and low awareness among public and medical professionals, the optimal genetic screening strategy remains unknown. We conducted a pilot study of Fragile X carrier screening in China, involving 22,245 pregnant women and women with childbearing intentions, divided into control and pilot groups. The prevalence of Fragile X carriers in the control group was 1 of 850, similar to East Asian populations. Strikingly, the prevalence of Fragile X carriers in the pilot group was 1 of 356, which can be attributed to extensive medical training, participant education, and rigorous genetic counseling and testing protocols. Cost-effectiveness analyses of four strategies-no screening, population-based screening, targeted screening, and our pilot screening-indicated that our pilot screening was the most cost-effective option. A follow-up survey revealed that 55% of respondents reported undergoing screening because of their family history. We have successfully established a standardized system, addressing the challenges of low prevalence, limited awareness, and genetic testing complexities. Our study provides practical recommendations for implementing Fragile X carrier screening in China.

Establishment and Validation of a Risk Prediction Model for Non-Invasive Ventilation Failure After Birth in Premature Infants with Gestational Age < 32 Weeks

OBJECTIVES

This study was performed to construct and validate a risk prediction model for non-invasive ventilation (NIV) failure after birth in premature infants with gestational age < 32 weeks.

METHODS

The data were derived from the multicenter retrospective study program - Jiangsu Provincial Neonatal Respiratory Failure Collaboration Network from Jan 2019 to Dec 2021. The subjects finally included were preterm infants using NIV after birth with gestational age less than 32 weeks and admission age within 72 h. After screening by inclusion and exclusion criteria, 1436 babies were subsequently recruited in the study, including 1235 infants in the successful NIV group and 201 infants in the failed NIV group.

RESULTS

(1) Gestational age, 5 min Apgar, Max FiO2 during NIV, and FiO2 fluctuation value during NIV were selected by univariate and multivariate analysis. (2) The area under the curve of the prediction model was 0.807 (95% CI: 0.767-0.847) in the training set and 0.825 (95% CI: 0.766-0.883) in the test set. The calibration curve showed good agreement between the predicted probability and the actual observed probability (Mean absolute error = 0.008 for the training set; Mean absolute error = 0.012 for the test set). Decision curve analysis showed good clinical validity of the risk model in the training and test cohorts.

CONCLUSION

This model performed well on dimensions of discrimination, calibration, and clinical validity. This model can serve as a useful tool for neonatologists to predict whether premature infants will experience NIV failure after birth.

Decline in reproductive health and its transgenerational lag effect

In the last two decades, there has been a fast-growing prevalence of infertility reported in China. Moreover, Chinese reproductive health has shown a clear decline. Thus, it is imperative to determine the precipitating causes and the root causes of this decline. Environmental and climate risks (ECRs) may cause the decline in reproductive health. Experimental findings have shown that the impact of ECRs on reproductive health can be passed down from both males and females to their offspring, demonstrating an intergenerational and transgenerational lag effect. We perceive that the declined reproductive health may lead to negative demographic consequences in China; therefore, we suggest the following five regulations be implemented: (i) prevent Chinese of childbearing age from exposure to ECRs; (ii) further develop and promote assisted reproductive technology and set up sperm and ovum banks on a national scale; (iii) quantitatively establish the causality between fathers and mothers who suffer from ECRs and the impaired reproductive health in their progeny; (iv) teach ECRs-health knowledge in psychotherapeutic training and continuing education; and (v) propagate and further promote common prosperity.

Descriptive epidemiology of gastroschisis in China from 2007 to 2020: a nationwide surveillance-based study

BACKGROUND

Gastroschisis is a common abdominal wall defect that increases infant mortality risk and health care costs. However, recent epidemiological data on gastroschisis in China is limited.

METHODS

Using 2007-2020 data from the Chinese Birth Defects Monitoring Network (CBDMN), we analyzed gastroschisis prevalence rates stratified by birth year, maternal age group, residence area, geographical region, and infant sex. We also examined the temporal variations in prevalence, pregnancy outcomes of affected infants, prenatal diagnoses, and co-occurring anomalies.

RESULTS

From 2007 to 2020, a total of 6,813 cases of gastroschisis were identified among 25,909,000 births, comprising 4,675 isolated and 2,138 non-isolated cases. Prevalence rates per 10,000 live and still births were 2.63, 1.80, and 0.83 for the overall, isolated, and non-isolated gastroschisis, respectively, all showing a decreasing trend over the study period. The prevalence of overall gastroschisis varied significantly by maternal age (< 20 years, 9.88/10,000; 20-24 years, 4.17/10,000; 25-29 year, 2.08/10,000; 30-34 years, 1.88/10,000;≥35 years, 2.24/10,000), maternal residence (urban, 2.45/10,000; rural, 2.85/10,000), geographic region (central, 2.54/10,000; east, 2.57/10,000; west, 2.80/10,000), and infant sex (male, 2.13/10,000; female, 1.79/10,000). Non-isolated gastroschisis cases had a higher early neonatal mortality rate than isolated cases (41.91% vs. 28.10%) and frequently co-occurred with musculoskeletal anomalies.

CONCLUSIONS

This study highlights a declining trend in gastroschisis prevalence in Chinese population, a contrast to previous studies, and underscores the need for improved perinatal management due to adverse pregnancy outcomes associated with this condition.

Disease burden and attributable risk factors of lip and oral cavity cancer in China from 1990 to 2021 and its prediction to 2031

Aims

This study addresses the essential need for updated information on the burden of lip and oral cavity cancer (LOC) in China for informed healthcare planning. We aim to estimate the temporal trends and the attributable burdens of selected risk factors of LOC in China (1990-2021), and to predict the possible trends (2022-2031).

Subject and methods

Analysis was conducted using data from the Global Burden of Disease study (GBD) 2021, encompassing six key metrics: incidence, mortality, prevalence, disability-adjusted life years (DALYs), years lived with disability (YLDs), and years of life lost (YLLs). Absolute number and age-standardized rates, alongside 95% uncertainty intervals, were computed. Forecasting of disease burden from 2022 to 2031 was performed using an autoregressive integrated moving average (ARIMA) model.

Results

Over the observed period (1990-2021), there were notable increases in the number of deaths (142.2%), incidence (283.7%), prevalence (438.0%), DALYs (109.2%), YLDs (341.2%), and YLLs (105.1%). Age-standardized rates demonstrated notable changes, showing decreases and increases of -5.8, 57.3, 143.7, -8.9%, 85.8%, and - 10.7% in the respective metrics. The substantial majority of LOC burden was observed among individuals aged 40-79 years, and LOC may exhibit a higher burden among males in China. From 2022 to 2031, the age-standardized rate of incidence, prevalence, and YLDs of LOC showed upward trends; while mortality, DALYs, and YLLs showed downward trends, and their estimated values were predicted to change to 2.72, 10.47, 1.11, 1.10, 28.52, and 27.43 per 100,000 in 2031, respectively. Notably, tobacco and high alcohol use emerged as predominant risk factors contributing to the burden of LOC.

Conclusion

Between 1990 and 2021, the disability burden from LOC in China increased, while the death burden decreased, and projections suggest these trends will persist over the next decade. A significant portion of this disease burden to modifiable risk factors, specifically tobacco use and excessive alcohol consumption, predominantly affecting males and individuals aged 40-79 years. Attention to these areas is essential for implementing targeted interventions and reducing the impact of LOC in China.

Rac1 promotes the lipopolysaccharide-induced inflammatory response and contraction-associated proteins (CAPs) expression in mouse uterine smooth muscle cells

Activation of the maternal immune system leads to a downstream cascade of proinflammatory events that culminate in the activation of spontaneous uterine contractions, which is associated with preterm birth. Ras-related C3 botulinum toxin substrate 1 (Rac1) is a crucial protein related to cell contraction and inflammation. The main purpose of this study was to explore the role and function of Rac1's regulation of inflammation through in- vivo and in-vitro experiments. Rac1 inhibitor was used in animal model of preterm birth and cells isolated from the uterine tissues of pregnant mice on gestational day 16 were transfected with adenovirus to knockdown or overexpress Rac1 and treated with the Calcium-calmodulin-dependent protein kinase II (CaMKII) inhibitor KN93. The expression of Rac1, uterine contraction-associated proteins (CAPs) (COX-2 and Connexin43), and inflammatory cytokines, were assessed by Western blotting and RTPCR. LPS upregulated Rac1, COX-2 and Connexin43 expression in uterine smooth muscle cells (USMCs). The expression of inflammatory cytokines, COX-2, and Connexin43 was significantly decreased in shRac1-transfected cells compared with cells stimulated with LPS only. Rac1 overexpression led to an increase in the expression of inflammatory cytokines, COX-2, and Connexin43. Furthermore, after Rac1 overexpression, KN93 reduced the expression of uterine contraction-associated proteins and inflammatory cytokines. It is thought that the effect of Rac1 on inflammatory cytokine and contraction-associated protein expression in USMCs is mediated by CaMKII. Rac1 can modulate the expression of contraction-associated proteins and inflammatory cytokines through the CaMKII pathway. Rac1 could be an effective therapeutic target for improving the outcome of preterm birth.

Preconception mitochondrial DNA copy number plays a crucial role in linking prenatal air pollution with the risk of preterm birth

The relationship between maternal peripheral blood mitochondrial DNA and adverse pregnancy outcomes, specifically preterm birth (PTB), remains uncertain. To investigate the effects of preconception mitochondrial DNA copy number (mtDNAcn) on the association between prenatal air pollutants exposure and PTB risk, a total of 1871 expectant mothers from six regions in Henan Province were recruited. Information regarding air pollutants was obtained from 151 environmental monitoring sites, and relative mtDNAcn was evaluated using real-time PCR analysis. After adjusting for potential confounding variables, it was determined that the risk of PTB increased with elevated levels of inhalable particulate matter (PM10), fine particulate matter (PM2.5), sulfur dioxide (SO2), carbon monoxide (CO) and ozone (O3) exposure (P < 0.05) but decreased with higher nitrogen dioxide (NO2) exposure (0.05 < P < 0.10) during the entire pregnancy. Additionally, the preconception relative mtDNAcn was lower in the PTB group (0.82 ± 0.23) compared to the term group (0.92 ± 0.29). Furthermore, for each 0.1-unit increase in preconception mtDNAcn, the risk of PTB decreased by 14.8%. Stratified analyses revealed that the risk of PTB rose with increasing O3 concentrations, regardless of the relative mtDNAcn. Moreover, the study found a significant association between PTB risk and prenatal exposure to elevated PM10, PM2.5, SO2, and CO, particularly in mothers with low mtDNAcn (≤0.88) (P < 0.05). Conversely, a decrease in the PTB risk was observed with elevated NO2 exposure in mothers with high mtDNAcn (>0.88). Interaction analysis revealed that exposure to PM10, PM2.5, SO2, NO2, and CO interacted with mtDNAcn, respectively, affecting PTB risk (P-interaction<0.05). These findings indicate a noteworthy association between PTB risk and prenatal air pollutants exposure, which is influenced by the preconception mtDNAcn.

Maternal Characteristics and Prevalence of Infants Born Small for Gestational Age

Importance

Being born small for gestational age (SGA) is a risk factor for neonatal mortality and adverse outcomes in the short and long term. The maternal profile in China has substantially changed over the past decade, which may affect the risk of infants born SGA.

Objectives

To analyze the prevalence of infants born SGA from 2012 through 2020 and explore the association of maternal sociodemographic characteristics and other factors with that prevalence.

Design, Setting, and Participants

This cross-sectional study examined data from the National Maternal Near Miss Surveillance System on women who delivered singleton live births at gestational ages of 28 to 42 weeks from January 1, 2012, through December 31, 2020, in China. Statistical analysis was performed from December 2022 to September 2023.

Exposures

Characteristics of delivery (year, region of country, and hospital level), mother (age, educational level, marital status, prenatal visits, parity, preexisting diseases, or prenatal complications), and newborn (birth weight, sex, and gestational age).

Main Outcomes and Measures

Prevalence of infants born SGA stratified by severity and by region of the country, changes in prevalence based on log-linear Poisson regression with robust variance, and association of maternal characteristics with changes in prevalence of infants born SGA between 2012 and 2020 based on the Fairlie nonlinear mean decomposition.

Results

Among 12 643 962 births (6 572 548 [52.0%] male; median gestational age, 39 weeks [IQR, 38-40 weeks]), the overall weighted prevalence of infants born SGA was 6.4%, which decreased from 7.3% in 2012 to 5.3% in 2020, translating to a mean annual decrease rate of 3.9% (95% CI, 3.3%-4.5%). The prevalence of infants born SGA decreased from 2.0% to 1.2% for infants with severe SGA birth weight and from 5.3% to 4.1% for those with mild to moderate SGA birth weight. The mean annual rate of decrease was faster for infants with severe SGA birth weight than for those with mild to moderate SGA birth weight (5.9% [95% CI, 4.6%-7.1%] vs 3.2% [95% CI, 2.6%-3.8%]) and was faster for the less developed western (5.3% [95% CI, 4.4%-6.1%]) and central (3.9% [95% CI, 2.9%-4.8%]) regions compared with the eastern region (2.3% [95% CI, 1.1%-3.4%]). Two-thirds of the observed decrease in the prevalence of infants born SGA could be accounted for by changes in maternal characteristics, such as educational level (relative association, 19.7%), age (relative association, 18.8%), prenatal visits (relative association, 20.4%), and parity (relative association, 19.4%). Conversely, maternal preexisting diseases or prenatal complications counteracted the decrease in the prevalence of infants born SGA (-6.7%).

Conclusions and Relevance

In this cross-sectional study of births in China from 2012 to 2020, maternal characteristics changed and the prevalence of infants born SGA decreased. Future interventions to reduce the risk of infants born SGA should focus on primary prevention.

Parental perceptions and experiences of kangaroo care for preterm infants in neonatal intensive care units in China: a qualitative study

BACKGROUND

kangaroo care (KC), endorsed by the World Health Organization, is an evidence-based intervention that plays a pivotal role in mitigating preterm infant mortality and morbidity. However, this intervention has not been fully integrated into healthcare systems in China. This study aimed to gain insight into parents' perceptions and experiences of KC for preterm infants to contribute to the KC implementation on a larger scale.

METHODS

This study employed a descriptive qualitative design, using face-to-face, semi-structured, in-depth interviews. Fifteen parents participating in KC for preterm infants in the neonatal intensive care units (NICUs) were purposively sampled from four hospitals across four cities in Zhejiang Province, China. Thematic analysis was employed to analyze the data.

RESULTS

Four themes and twelve subthemes regarding the parents' perceptions and experiences about KC were identified. The four themes included: (1) Low motivation upon initial engagement with KC, (2) Dynamic fluctuations of emotional states during KC, (3) Unexpected gains, and (4) Barriers to participation.

CONCLUSIONS

Parents' perceptions and experiences of KC was a staged process, with parents exhibiting distinct cognitive patterns and unique experiences at each stage. Overall, as KC progresses, parents' experiences tended to become increasingly positive, despite potential obstacles encountered along the way. To enhance the implementation of KC, healthcare providers could utilize prenatal and postnatal education programs. These programs aim to enhance the understanding of KC among parents of preterm infants, fostering sustained engagement in KC practices.

Exploring the association between atmospheric pollutants and preterm birth risk in a river valley city

Objective

To investigate the association between exposure to atmospheric pollutants and preterm birth in a river valley-type city and its critical exposure windows.

Methods

A retrospective cohort study was used to collect data from the medical records of preterm and full-term deliveries in two hospitals in urban areas of a typical river valley-type city from January 2018 to December 2019. A total of 7,288 cases were included in the study with general information such as pregnancy times, the number of cesarean sections, occupation, season of conception and regularity of the menstrual cycle. And confounding factors affecting preterm birth were inferred using the chi-square test. The effects of exposure to each pollutant, including particulate matter 2.5 (PM2.5), particulate matter 10 (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2), carbon monoxide (CO) and ozone (O3), during pregnancy on preterm birth and the main exposure windows were explored by establishing a logistic regression model with pollutants introduced as continuous variables.

Results

Maternal age, pregnancy times, number of births, number of cesarean sections, season of conception, complications diseases, comorbidities diseases, hypertension disorder of pregnancy and neonatal low birth weight of the newborn were significantly different between preterm and term pregnant women. Logistic regression analysis after adjusting for the above confounders showed that the risk of preterm birth increases by 0.9, 0.6, 2.4% in T2 and by 1.0, 0.9, 2.5% in T3 for each 10 μg/m3 increase in PM2.5, PM10, NO2 concentrations, respectively. The risk of preterm birth increases by 4.3% in T2 for each 10 μg/m3 increase in SO2 concentrations. The risk of preterm birth increases by 123.5% in T2 and increases by 188.5% in T3 for each 10 mg/m3 increase in CO concentrations.

Conclusion

Maternal exposure to PM2.5, PM10, NO2, CO was associated with increased risk on preterm birth in mid-pregnancy (T2) and late pregnancy (T3), SO2 exposure was associated with increased risk on preterm birth in mid-pregnancy (T2).

Mediating role of gestational weight gain in the relationship between socioeconomic status and preterm birth: a Chinese population-based study

BACKGROUND

The modifiable mechanisms underlying the association between socioeconomic status (SES) and preterm birth remain unclear. This study aimed to investigate the relationship between preterm birth and maternal SES or gestational weight gain (GWG), as well as the role of GWG in mediating SES disparities in preterm birth.

METHODS

Data was from a hospital-based sub-study of physical growth and development survey for Chinese newborns with various gestational ages. Singleton newborns aged from 24 to 42weeks' gestation and their mothers were included. Using information from maternal questionnaire, a composite SES was constructed with parental education and family annual income. GWG as mediator was calculated by deducting pre-pregnancy weight from maternal weight at delivery. Logistic regression model was adopted to investigate the association of preterm birth with SES or GWG. Causal mediation analysis was performed to measure mediating effect of GWG on the pathway from SES to preterm birth.

RESULTS

After controlling for potential confounders, risk of preterm birth was reduced by 12.4% (OR = 0.876, 95%CI:0.855-0.879) for per one-kilogram increase of GWG, and risk of preterm birth was reduced by 24% (OR = 0.760, 95%CI: 0.717-0.806) for per one-unit increase of SES score. Mediation analysis supported a significant association between higher SES and decreased risk of preterm partly through higher GWG, in which estimated proportion mediated by GWG was 13.04% (95%CI: 11.89-16.25). GWG also played a significant role as a mediator when socioeconomic status was indicated by maternal education, paternal education or family income. GWG mediated approximately 11.03% (95% CI: 8.56-18.25) of the total effect of SES on very preterm birth, which was greater than that for moderate preterm birth (6.72%, 95%CI: 2.72-31.52) and late preterm birth (9.04%, 95%CI: 5.24-24.04). A series of sensitive analysis confirmed the robustness of association of interest.

CONCLUSION

Increased GWG and higher socioeconomic status are strongly associated with a lower risk of preterm birth. GWG mediates socioeconomic disparities in preterm birth, most notably in very preterm birth. Understanding this mechanism will aid in the development of interventions and policy for maternal and child health care.

Healthcare providers' perceptions and experiences of kangaroo mother care for preterm infants in four neonatal intensive care units in China: a qualitative descriptive study

Background

Kangaroo mother care (KMC) is an evidence-based intervention that can effectively reduce morbidity and mortality in preterm infants, but it has yet to be widely implemented in health systems in China. Most qualitative studies on KMC for preterm infants focused on the experiences and influencing factors from the perspective of preterm infant parents, while neglecting the perspective of healthcare providers, who played a critical role in guiding KMC practice. Therefore, this study aimed to explore the perceptions and experiences of healthcare providers regarding their involvement in KMC implementation for preterm infants to promote the contextualized implementation of KMC.

Methods

A descriptive qualitative approach was adopted. A purposive sampling was used to select healthcare providers involved in KMC implementation in the neonatal intensive care units (NICUs) as participants from four tertiary hospitals across four cities in Zhejiang Province, China. Face-to-face semi-structured interviews were conducted to collect information. Thematic analysis was employed to analyze the data.

Results

Seventeen healthcare professionals were recruited, including thirteen nurses and four doctors in the NICUs. Four themes and twelve subthemes emerged: different cognitions based on different perspectives (acknowledged effects and benefits, not profitable economically), ambivalent emotions regarding KMC implementation (gaining understanding, gratitude and trust from parents, not used to working under parental presence, and concerning nursing safety issues), barriers to KMC implementation (lack of unified norms and standards, lack of systematic training and communication platform, insufficient human resources, and inadequate parental compliance) and suggestions for KMC implementation (improving equipment and environment, strengthening collaboration between nurses and doctors, and support from hospital managers).

Conclusions

Despite acknowledging the clinical benefits of KMC, the lack of economic incentives, concerns about potential risks, and various barriers hindered healthcare providers' intrinsic motivation to implement KMC in NICUs in China. To facilitate the effective implementation of KMC, hospital managers should provide bonuses and training programs for healthcare providers, while giving them recognition and encouragement to enhance their motivation to implement KMC.

Spatiotemporal Characteristics and Risk Factors for All and Severity-Specific Preterm Births in Southern China, 2014-2021: Large Population-Based Study

BACKGROUND

The worldwide incidence of preterm births is increasing, and the risks of adverse outcomes for preterm infants significantly increase with shorter gestation, resulting in a substantial socioeconomic burden. Limited epidemiological studies have been conducted in China regarding the incidence and spatiotemporal trends of preterm births. Seasonal variations in risk indicate the presence of possible modifiable factors. Gender influences the risk of preterm birth.

OBJECTIVE

This study aims to assess the incidence rates of preterm birth, very preterm birth, and extremely preterm birth; elucidate their spatiotemporal distribution; and investigate the risk factors associated with preterm birth.

METHODS

We obtained data from the Guangdong Provincial Maternal and Child Health Information System, spanning from January 1, 2014, to December 31, 2021, pertaining to neonates with gestational ages ranging from 24 weeks to 42 weeks. The primary outcome measures assessed variations in the rates of different preterm birth subtypes over the course of the study, such as by year, region, and season. Furthermore, we examined the relationship between preterm birth incidence and per capita gross domestic product (GDP), simultaneously analyzing the contributing risk factors.

RESULTS

The analysis incorporated data from 13,256,743 live births. We identified 754,268 preterm infants and 12,502,475 full-term infants. The incidences of preterm birth, very preterm birth, and extremely preterm birth were 5.69 per 100 births, 4.46 per 1000 births, and 4.83 per 10,000 births, respectively. The overall incidence of preterm birth increased from 5.12% in 2014 to 6.38% in 2021. The incidence of extremely preterm birth increased from 4.10 per 10,000 births in 2014 to 8.09 per 10,000 births in 2021. There was a positive correlation between the incidence of preterm infants and GDP per capita. In more developed economic regions, the incidence of preterm births was higher. Furthermore, adjusted odds ratios revealed that advanced maternal age, multiple pregnancies, and male infants were associated with an increased risk of preterm birth, whereas childbirth in the autumn season was associated with a protective effect against preterm birth.

CONCLUSIONS

The incidence of preterm birth in southern China exhibited an upward trend, closely linked to enhancements in the care capabilities for high-risk pregnant women and critically ill newborns. With the recent relaxation of China's 3-child policy, coupled with a temporary surge in advanced maternal age and multiple pregnancies, the risk of preterm birth has risen. Consequently, there is a pressing need to augment public health investments aimed at mitigating the risk factors associated with preterm birth, thereby alleviating the socioeconomic burden it imposes.

[Risk factors for bronchopulmonary dysplasia in twin preterm infants: a multicenter study]

OBJECTIVES

To investigate the risk factors for bronchopulmonary dysplasia (BPD) in twin preterm infants with a gestational age of <34 weeks, and to provide a basis for early identification of BPD in twin preterm infants in clinical practice.

METHODS

A retrospective analysis was performed for the twin preterm infants with a gestational age of <34 weeks who were admitted to 22 hospitals nationwide from January 2018 to December 2020. According to their conditions, they were divided into group A (both twins had BPD), group B (only one twin had BPD), and group C (neither twin had BPD). The risk factors for BPD in twin preterm infants were analyzed. Further analysis was conducted on group B to investigate the postnatal risk factors for BPD within twins.

RESULTS

A total of 904 pairs of twins with a gestational age of <34 weeks were included in this study. The multivariate logistic regression analysis showed that compared with group C, birth weight discordance of >25% between the twins was an independent risk factor for BPD in one of the twins (OR=3.370, 95%CI: 1.500-7.568, P<0.05), and high gestational age at birth was a protective factor against BPD (P<0.05). The conditional logistic regression analysis of group B showed that small-for-gestational-age (SGA) birth was an independent risk factor for BPD in individual twins (OR=5.017, 95%CI: 1.040-24.190, P<0.05).

CONCLUSIONS

The development of BPD in twin preterm infants is associated with gestational age, birth weight discordance between the twins, and SGA birth.

Prevalence of placenta previa among deliveries: An update systematic review and meta-analysis after the introduction of the two-child policy in Mainland China

Background

As birth policy can affect maternal and infant health, we sought to identify whether and how the introduction of the two-child policy might have affected the prevalence of placenta previa in pregnant women in mainland China.

Methods

In this update meta-analysis and systematic review, we searched PubMed, Web of Science, the Cochrane Library, Weipu, Wanfang, and the China National Knowledge Infrastructure (CNKI) databases for studies evaluating the prevalence of placenta previa in China published between the inception of each database and March 2024, with no restrictions. Two investigators independently extracted the data from each included study. We then combined the prevalence of placenta previa using random-effects models.

Results

We included 128 studies in our analysis, 48 more than in our previous review. The prevalence of placenta previa among Chinese pregnant women was 1.44% (95% confidence interval (CI) = 1.32, 1.56). After the implementation of the two-child policy, the prevalence increased significantly, from 1.25% (95% CI = 1.16, 1.34) to 4.12% (95% CI = 3.33, 4.91).

Conclusions

The prevalence of placenta previa increased significantly from the one-child policy period to the two-child policy period among mainland Chinese pregnant women, with varying trends across regions. This change requires the attention of health officials and timely adjustment of resource allocation policies.

Registration

PROSPERO: CRD42021262309.

Trend of Mortality Due to Congenital Anomalies in Children Younger Than 5 Years in Eastern China, 2012-2021: Surveillance Data Analysis

BACKGROUND

As one of the leading causes of child mortality, deaths due to congenital anomalies (CAs) have been a prominent obstacle to meet Sustainable Development Goal 3.2.

OBJECTIVE

We conducted this study to understand the death burden and trend of under-5 CA mortality (CAMR) in Zhejiang, one of the provinces with the best medical services and public health foundations in Eastern China.

METHODS

We used data retrieved from the under-5 mortality surveillance system in Zhejiang from 2012 to 2021. CAMR by sex, residence, and age group for each year was calculated and standardized according to 2020 National Population Census sex- and residence-specific live birth data in China. Poisson regression models were used to estimate the annual average change rate (AACR) of CAMR and to obtain the rate ratio between subgroups after adjusting for sex, residence, and age group when appropriate.

RESULTS

From 2012 to 2021, a total of 1753 children died from CAs, and the standardized CAMR declined from 121.2 to 62.6 per 100,000 live births with an AACR of -9% (95% CI -10.7% to -7.2%; P<.001). The declining trend was also observed in female and male children, urban and rural children, and neonates and older infants, and the AACRs were -9.7%, -8.5%, -8.5%, -9.2%, -12%, and -6.3%, respectively (all P<.001). However, no significant reduction was observed in children aged 1-4 years (P=.22). Generally, the CAMR rate ratios for male versus female children, rural versus urban children, older infants versus neonates, and older children versus neonates were 1.18 (95% CI 1.08-1.30; P<.001), 1.20 (95% CI 1.08-1.32; P=.001), 0.66 (95% CI 0.59-0.73; P<.001), and 0.20 (95% CI 0.17-0.24; P<.001), respectively. Among all broad CA groups, circulatory system malformations, mainly deaths caused by congenital heart diseases, accounted for 49.4% (866/1753) of deaths and ranked first across all years, although it declined yearly with an AACR of -9.8% (P<.001). Deaths due to chromosomal abnormalities tended to grow in recent years, although the AACR was not significant (P=.90).

CONCLUSIONS

CAMR reduced annually, with cardiovascular malformations ranking first across all years in Zhejiang, China. Future research and practices should focus more on the prevention, early detection, long-term management of CAs and comprehensive support for families with children with CAs to improve their survival chances.

Methyl-CpG-binding protein 2 regulates CYP27A1-induced myometrial contraction during preterm labor

Persistent and intense uterine contraction is a risk factor for preterm labor. We previously found that methyl-CpG-binding protein 2 (MeCP2), as a target of infection-related microRNA miR-212-3p, may play an inhibitory role in regulating myometrium contraction. However, the molecular mechanisms by which MeCP2 regulates myometrial contraction are still unknown. In this study, we found that MeCP2 protein expression was lower in myometrial specimens obtained from preterm labor cases, compared to those obtained from term labor cases. Herein, using RNA sequence analysis of global gene expression in human uterine smooth muscle cells (HUSMCs) following siMeCP2, we show that MeCP2 silencing caused dysregulation of the cholesterol metabolism pathway. Notably, MeCP2 silencing resulted in the upregulation of CYP27A1, the key enzyme involved in regulating cholesterol homeostasis, in HUSMCs. Methylation-specific PCR, chromatin immunoprecipitation, and dual luciferase reporter gene technology indicated that MeCP2 could bind to the methylated CYP27A1 promoter region and repress its transcription. Administration of siCYP27A1 in a lipopolysaccharide (LPS)-induced preterm labor mouse model delayed the onset of preterm labor. Human preterm myometrium and the LPS-induced preterm labor mouse model both showed lower expression of MeCP2 and increased expression of CYP27A1. These results demonstrated that aberrant upregulation of CYP27A1 induced by MeCP2 silencing is one of the mechanisms facilitating inappropriate myometrial contraction. CYP27A1 could be exploited as a novel therapeutic target for preterm birth.

The association between pregnancy levels of blood lipids and the risk of preterm birth

Preterm labor, a condition associated with various risk factors such as a history of prior preterm birth (PTB) and multiple pregnancies, has recently seen an increasing focus on its potential link with dyslipidemia. This study aims to investigate the relationship between dyslipidemia in expectant mothers and the risks of PTB. We studied 6963 mothers who gave birth at the International Peace Maternal and Child Health Hospital of Shanghai Jiaotong University School of Medicine in 2020, among which, 437 women had PTB. We extracted clinical and lipid data from electronic records, using multivariable logistic regression and restricted cubic spline models to explore the link between lipid concentrations (by quartiles) in pregnancy stages and PTB risk. The PTB rate was 6.3%. Early pregnancy in the PTB group showed elevated ApoA, ApoB, CHOL, LDL, and TG levels compared to controls (all P < 0.05). Late pregnancy showed no notable lipid differences. Multivariable analysis revealed elevated ApoA, TG, higher age, BMI ≥ 28 kg/m2, hypertension, assisted reproductive technology and gestational diabetes as PTB risk factors (all P < 0.05). After adjustments, higher ApoA, ApoB, CHOL and TG levels correlated with increased PTB risk. Using the lowest quartile, the adjusted ORs for early pregnancy's highest quartile of ApoA, ApoB, CHOL and TG were 1.348, 1.442, 1.442 and 2.156, respectively. Our findings indicate that dyslipemia in early pregnancy, including elevated levels of ApoA, ApoB, CHOL and TG, are associated with PTB. Managing lipid abnormalities during pregnancy may help reduce the risk of PTB.

Inverse association between maternal serum concentrations of trace elements and risk of spontaneous preterm birth: a nested case-control study in China

Few studies have evaluated the joint effect of trace elements on spontaneous preterm birth (SPTB). This study aimed to examine the relationships between the individual or mixed maternal serum concentrations of Fe, Cu, Zn, Se, Sr and Mo during pregnancy, and risk of SPTB. Inductively coupled plasma MS was employed to determine maternal serum concentrations of the six trace elements in 192 cases with SPTB and 282 controls with full-term delivery. Multivariate logistic regression, weighted quantile sum regression (WQSR) and Bayesian kernel machine regression (BKMR) were used to evaluate the individual and joint effects of trace elements on SPTB. The median concentrations of Sr and Mo were significantly higher in controls than in SPTB group (P < 0·05). In multivariate logistic regression analysis, compared with the lowest quartile levels of individual trace elements, the third- and fourth-quartile Sr or Mo concentrations were significantly associated with reduced risk of SPTB with adjusted OR (aOR) of 0·432 (95 CI < 0·05). In multivariate logistic regression analysis, compared with the lowest quartile levels of individual trace elements, the third- and fourth-quartile Sr or Mo concentrations were significantly associated with reduced risk of SPTB with adjusted aOR of 0·432 (95 % CI 0·247, 0·756), 0·386 (95 % CI 0·213, 0·701), 0·512 (95 % CI 0·297, 0·883) and 0·559 (95 % CI 0·321, 0·972), respectively. WQSR revealed the inverse combined effect of the trace elements mixture on SPTB (aOR = 0·368, 95 % CI 0·228, 0·593). BKMR analysis confirmed the overall mixture of the trace elements was inversely associated with the risk of SPTB, and the independent effect of Sr and Mo was significant. Our findings suggest that the risk of SPTB decreased with concentrations of the six trace elements, with Sr and Mo being the major contributors.

The prevalence of preterm and low birth weight infants among migrant women in the Pearl River Delta region, China: a population-based birth cohort study

BACKGROUND

The existing literature evaluating the association between neonatal morbidity and migrant status presents contradictory results. The purpose of this study was to compare the risk of preterm birth (PTB) and low birth weight (LBW) among newborns from local and migrant women in China's Pearl River Delta (PRD) region.

METHODS

In this observational population-based study, we included all live singleton deliveries from PRD region local women and migrant women. Data were sourced from the Guangdong Medical Birth Registry Information System between Jan 1, 2014, and Dec 31, 2020. Women were categorized into three groups by maternal migrant status: local women from PRD region, migrant women from Guangdong province or from other provinces. The outcome variables that were examined included two adverse birth outcomes: PTB and LBW. The association between the risk of PTB and LBW and maternal migrant status was assessed using logistic regression.

RESULTS

During 2014-2020, 5,219,133 single live deliveries were recorded, corresponding 13.22% to local women and the rest to migrant women coming from Guangdong (53.51%) and other provinces (33.26%). PTB prevalence was highest among local women (5.79%), followed by migrant women from Guangdong (5.29%), and the lowest among migrants from other provinces (4.95%). This association did not change after including maternal age, infant sex, delivery mode, and birth season in the models. Compared to local women, migrant women from other provinces had a lower risk of LBW (4.00% vs. 4.98%, P < 0.001). The prevalence of PTB and LBW was higher among local women than migrants. The odds of delivery PTB and LBW were higher for women who were age ≥ 35. Among the three maternal migration groups, the age-LBW association displayed a typical U-shaped pattern, with those in the youngest (16-24 years) and oldest (≥ 35) age categories exhibiting the higher odds of delivering a LBW neonate. With respect to infant sex, the prevalence of PTB was significantly higher in males than females among the three maternal migration groups. An opposite trend was found for LBW, and the prevalence of LBW was higher in females among the three maternal migration groups.

CONCLUSION

The findings of this study contribute to the understanding of the epidemiology of PTB and LBW among migrant women. Our study suggests that it is the health and robust nature of migrant mothers that predisposes them to better birth outcomes. It is important to recognize that the results of this study, while supportive of the healthy migrant effect, cannot be considered definitive without some exploration of motivation for moving and changes in lifestyle postmigration.

Preterm birth, a consequence of immune deviation mediated hyperinflammation

Preterm birth represents a multifaceted syndrome with intricacies still present in our comprehension of its etiology. In the context of a semi-allograft, the prosperity from implantation to pregnancy to delivery hinges on the establishment of a favorable maternal-fetal immune microenvironment and a successful trilogy of immune activation, immune tolerance and then immune activation transitions. The occurrence of spontaneous preterm birth could be related to abnormalities within the immune trilogy, stemming from deviation in maternal and fetal immunity. These immune deviations, characterized by insufficient immune tolerance and early immune activation, ultimately culminated in an unsustainable pregnancy. In this review, we accentuated the role of both innate and adaptive immune reason in promoting spontaneous preterm birth, reviewed the risk of preterm birth from vaginal microbiome mediated by immune changes and the potential of vaginal microbiomes and metabolites as a new predictive marker, and discuss the changes in the role of progesterone and its interaction with immune cells in a preterm birth population. Our objective was to contribute to the growing body of knowledge in the field, shedding light on the immunologic reason of spontaneous preterm birth and effective biomarkers for early prediction, providing a roadmap for forthcoming investigations.

Longitudinal Cervical Length Measurements and Spontaneous Preterm Birth in Singleton and Twin Pregnancies

Importance

Changes in cervical length in twin pregnancies exhibit various patterns, but it is unclear whether the mechanism underlying spontaneous preterm birth (sPTB) is consistent. The existence of detailed phenomena in singleton pregnancies is also unclear.

Objectives

To explore the different patterns in cervical length trajectories in singleton and twin pregnancies and to analyze whether the immunological mechanisms of sPTB are consistent among these cervical length patterns.

Design, Setting, and Participants

This cohort study recruited pregnant individuals who received antenatal care and delivered at Peking University Third Hospital in Beijing, China, between January 1, 2014, and December 31, 2022. Individuals with singleton and twin pregnancies were included.

Exposures

Cervical length measurements and white blood cell (WBC) indicators.

Main Outcomes and Measures

The primary outcome was sPTB. Longitudinal trajectory cluster analysis was used to identify patterns of changes in cervical length in singleton and twin pregnancies. A random-effects model with cubic spline was used to fit and compare the longitudinal trajectory of WBC indicators among early preterm birth, moderate to late preterm birth, and term birth.

Results

A total of 43 559 pregnant individuals were included; of these, 41 706 had singleton pregnancies (mean [SD)] maternal age, 33.0 [4.0] years) and 1853 had twin pregnancies (mean [SD] maternal age, 33.3 [3.6] years). Two distinct patterns of cervical length changes were observed in both singleton and twin pregnancies: shortened (21 366 singletons and 546 twins) and stable (20 340 singletons and 1307 twins). In singleton pregnancies, WBC count was associated with early sPTB in individuals with both shortened cervix (odds ratio [OR], 1.35; 95% CI, 1.00-1.82) and stable cervix (OR, 1.64; 95% CI, 1.07-2.50). However, for twin pregnancies, the association of WBC count (OR, 3.13; 95% CI, 1.58-6.18) with the risk of early sPTB was observed only in individuals with a shortened cervix.

Conclusions and Relevance

This study identified 2 distinct cervical length patterns: shortened and stable. These patterns revealed 2 preterm birth mechanisms in twin pregnancies, with the immunopathogenesis of sPTB found only in the shortened cervix pattern; in singleton pregnancies, maternal immune response was associated with a higher risk of sPTB regardless of a shortened or stable cervix.

Risk factors for severe bronchopulmonary dysplasia in a Chinese cohort of very preterm infants

OBJECTIVES

To examine the risk factors for severe bronchopulmonary dysplasia (BPD) in a cohort of very preterm infants (VPIs) in China, as BPD is common among VPIs and associated with a high mortality rate.

METHODS

In this multicenter retrospective study, medical records from infants with BPD born at gestation age (GA) of <32 weeks with birth weight (BW) of <1,500 grams (g) in 7 regions of China were included. The cohort was stratified into different BPD severity groups based on their fraction of inspired oxygen requirement at a modified GA of 36 weeks or post discharge. Risk factors were identified using logistic regression analysis.

RESULTS

A significant inverse correlation was revealed between BPD severity and both GA and BW (p<0.001). Independent risk factors for severe BPD (sBPD) were identified as invasive mechanical ventilation (≥7d), multiple blood transfusion (≥3), nosocomial infection (NI), hemodynamically significant patent ductus arteriosus (hsPDA), delayed initiation of enteral nutrition, and longer time to achieve total caloric intake of 110 kcal/kg. Conversely, administration of antenatal steroids was associated with reduced risk of sBPD.

CONCLUSION

Our study not only reaffirmed the established risk factors of low GA and BW for sBPD in VPIs, but also identified additional, potentially modifiable risk factors. Further research is warranted to explore whether intervention in these modifiable factors might reduce the risk of sBPD.Clinical Trial Reg. No.: ChiCTR1900023418.

Genetic Factors Associated With Adverse Pregnancy Outcomes in Chronic Pancreatitis

INTRODUCTION

The effects of genetic factors on pregnancy outcomes in chronic pancreatitis (CP) patients remain unclear. We evaluated the impacts of clinical features and mutations in main CP-susceptibility genes ( SPINK1 , PRSS1 , CTRC , and CFTR ) on pregnancy outcomes in Chinese CP patients.

METHODS

This was a prospective cohort study with 14-year follow-up. The sample comprised female CP patients with documented pregnancy and known genetic backgrounds. Adverse pregnancy outcomes were compared between patients with and without gene mutations. Univariate and multivariate analyses were performed to determine the impact factors for adverse pregnancy outcomes.

RESULTS

Totally, 160 female CP patients with a pregnancy history were enrolled; 59.4% of patients carried pathogenic mutations in CP-susceptibility genes. Adverse pregnancy outcomes occurred in 38 patients (23.8%); the prevalence of adverse outcomes was significantly higher in those harboring gene mutations than those without (30.5% vs 13.8%, P = 0.015). Notably, the rates of preterm delivery (12.6% vs 3.1%, P = 0.036) and abortion (17.9% vs 4.6%, P = 0.013) were remarkably higher in patients with gene mutations (especially SPINK1 mutations) than those without. In multivariate analyses, both CP-susceptibility gene mutations (odds ratio, 2.52; P = 0.033) and SPINK1 mutations (odds ratio, 2.60; P = 0.037) significantly increased the risk of adverse pregnancy outcomes. Acute pain attack during pregnancy was another risk factor for adverse pregnancy outcomes.

DISCUSSION

Pathogenic mutations in CP-susceptibility genes, especially SPINK1 , were independently related to adverse pregnancy outcomes in CP patients. Significant attention should be paid to pregnant females harboring CP-susceptibility gene mutations (ClinicalTrials.gov: NCT06055595).

The Status and Influencing Factors of COVID-19 Vaccination for 3-7-Year-Old Children Born Prematurely

Objective

To explore the status and influencing factors of COVID-19 vaccination for 3-7-year-old children born prematurely.

Methods

A questionnaire was administered to parents of preterm infants born between 1 January 2016 and 31 December 2019 in Gansu Maternal and Child Health Hospital using convenience sampling.

Results

It was found that 96.81% of 282 parents had known about COVID-19 vaccines and acquired COVID-19- and vaccine-related knowledge primarily through WeChat (104/282, 36.88%) and TikTok (91/282, 32.27%). Most parents of the group whose children were vaccinated with a COVID-19 vaccine believed that this approach was effective in preventing COVID-19 (49.75%), whereas most parents of the group whose children were not vaccinated were worried about the adverse reaction and safety of the vaccine (45.88%). According to the regression analysis, the risk factors of children born prematurely receiving a COVID-19 vaccine were no vaccination against COVID-19 in the mothers (odds ratio [OR]=48.489, 95% CI: 6.524-360.406) and in younger children (OR=12.157, 95% CI: 6.388-23.139). Previous history of referral (OR=0.229, 95% CI: 0.057-0.920), history of diseases (OR=0.130, 95% CI: 0.034-0.503) and high educational level of guardians (OR=0.142, 95% CI: 0.112-0.557) were protective factors for children born prematurely to receive COVID-19 vaccination.

Conclusion

There is a relatively high proportion of children born prematurely receiving COVID-19 vaccination, but some people still have concerns. Publicity in the later stage can be conducted through WeChat, TikTok and other social media platforms, with special attention paid to the populations with lower education levels.

Trajectories tracking of maternal and neonatal health in eastern China from 2010 to 2021: A multicentre cross-sectional study

Background

China's fertility policy has dramatically changed in the past decade with the successive promulgation of the partial two-child policy, universal two-child policy and three-child policy. The trajectories of maternal and neonatal health accompanied the changes in fertility policy are unknown.

Methods

We obtained data of 280 203 deliveries with six common pregnancy complications and thirteen perinatal outcomes between 2010 and 2021 in eastern China. The average annual percent change (AAPC) was calculated to evaluated the temporal trajectories of obstetric characteristics and adverse outcomes during this period. Then, the autoregressive integrated moving average (ARIMA) models were constructed to project future trend of obstetric characteristics and outcomes until 2027.

Results

The proportion of advanced maternal age (AMA), assisted reproduction technology (ART) treatment, gestational diabetes mellitus (GDM), anaemia, thrombocytopenia, thyroid dysfunction, oligohydramnios, placental abruption, small for gestational age (SGA) infants, and congenital malformation significantly increased from 2010 to 2021. However, the placenta previa, large for gestational age (LGA) infants and stillbirth significantly decreased during the same period. The AMA and ART treatment were identified as independent risk factors for the uptrends of pregnancy complications and adverse perinatal outcomes. The overall caesarean section rate remained above 40%. Importantly, among multiparas, a previous caesarean section was found to be associated with a significantly reduced risk of hypertensive disorders of pregnancy (HDP), premature rupture of membranes (PROM), placenta previa, placental abruption, perinatal asphyxia, LGA infants, stillbirths, and preterm births. In addition, the ARIMA time series models predicted increasing trends in the ART treatment, GDM, anaemia, thrombocytopenia, postpartum haemorrhage, congenital malformation, and caesarean section until 2027. Conversely, a decreasing trend was predicted for HDP, PROM, and placental abruption premature, LGA infants, SGA infants, perinatal asphyxia, and stillbirth.

Conclusions

Maternal and neonatal adverse outcomes became more prevalent from 2010 to 2021 in China. Maternal age and ART treatment were independent risk factors for adverse obstetric outcomes. The findings offered comprehensive trajectories for monitoring pregnancy complications and perinatal outcomes in China, and provided robust intervention targets in obstetric safety. The development of early prediction models and the implementation of prevention efforts for adverse obstetric events are necessary to enhance obstetric safety.

Persistence of antibodies 5 years after hepatitis B vaccination in preterm birth children: A retrospective cohort study using real-world data

Previous studies did not provide substantial evidence for long-term immune persistence after the hepatitis B vaccine (HepB) in preterm birth (PTB) children. Consequently, there is ongoing controversy surrounding the booster immunization strategy for these children. Therefore, we conducted a retrospective cohort study to evaluate the disparities in immune persistence between PTB children and full-term children. A total of 1027 participants were enrolled in this study, including 505 PTB children in the exposure group and 522 full-term children in the control group. The negative rate of hepatitis B surface antibody (HBsAb) in the PTB group was significantly lower than that in the control group (47.9% vs. 41.4%, p = .035). The risk of HBsAb-negative in the exposure group was 1.5 times higher than that in the control group (adjusted odds ratio [aOR] = 1.5, 95% confidence interval [CI]: 1.1-2.0). The geometric mean concentration (GMC) of HBsAb was much lower for participants in the exposure group compared to participants in the control group (9.3 vs. 12.4 mIU/mL, p = .029). Subgroup analysis showed that the very preterm infants (gestational age <32 weeks) and the preterm low birth weight infants (birth weight <2000 g) had relatively low GMC levels of 3.2 mIU/mL (95% CI: 0.9-11.1) and 7.9 mIU/mL (95% CI: 4.2-14.8), respectively. Our findings demonstrated that PTB had a significant impact on the long-term persistence of HBsAb after HepB vaccination. The very preterm infants (gestational age <32 weeks) and the preterm low birth weight infants (birth weight <2000 g) may be special populations that should be given priority for HepB booster vaccination.

Fertility policy changes, maternal and foetal characteristics and birth timing patterns at a tertiary referral centre in Beijing: a ten-year retrospective study

OBJECTIVE

This study aimed to explore the impacts of the changing national fertility policy on maternal and fetal characteristics, and birth timing patterns and provide a basis for the management of the obstetric and midwifery workforce.

DESIGN

Retrospective cohort study.

SETTING

Data from medical register of a tertiary referral centre in Beijing, China.

PARTICIPANTS

We included 20 334 births with a gestational age more than 28 weeks during January 2013-September 2023.

MAIN OUTCOMES

The main outcomes included birth numbers, maternal age, parity, birth modes, premature rates, neonatal birth weight, and birth timings.

RESULTS

The birth rates showed a general rising trend before 2016. Afterwards, the birth rates kept decreasing and reached the bottom level in 2022. The caesarean section rates showed a declining trend, while the assisted birth rates were progressively rising, especially among primiparous women. From 2013 to 2022, the proportions of multiparous women (increasing from 9.3% to 36.6%) and women with advanced maternal age (increasing from 11.4% to 34.5%) were on the rise, together with increasing rates of premature birth (increasing from 5.7% to 8.5%) and neonatal low birth weight (rising from 4.3% to 7.2%) in this population. This study found a significant peak of births between 14:00 and 15:00, which remained unchanged despite shifts in the fertility policy (p<0.001 and [Formula: see text] values close to 1, respectively).

CONCLUSION

The 'three-child' policy did not boost the birth rate further 2 years later after its enactment, and the proportion of multiparous women and women with advanced maternal age were on the rise, accompanied by an increase in rates of premature birth and low birth weight. Targeted training should be offered to healthcare professionals to empower them to deal with possible negative pregnancy outcomes and childbirth complications. Prepregnancy and antepartum education should be parity specific. Adequate midwifery staffing during this 14:00-15:00 is vital to promote a safe birth.

Association of maternal preconception blood pressure with preterm birth: a population-based cohort study

The association between maternal preconception blood pressure (BP) and preterm birth (PTB) is still unclear. The purpose of this study was to investigate the association between maternal preconception BP and PTB. This population-based cohort study included 715 984 Chinese women aged 20-49 years who participated in the National Free Preconception Health Examination Project and successfully had a singleton livebirth during 2014-2019 in Guangdong Province, China. Maternal preconception BP were measured by trained health workers. Multivariate logistic regression models and restricted cubic spline regressions were used to examine the association and dose-response relationship between maternal preconception BP and PTB, respectively. Maternal preconception hypertension was associated with the increased risk of PTB (adjusted odds ratios (aOR): 1.24; 95% CI: 1.14-1.34). Compared to women with normal preconception BP, the aORs for PTB were 1.09 (95% CI: 1.06-1.12), 1.24 (95% CI: 1.13-1.36), and 1.43 (95% CI: 1.15-1.79) for women with preconception elevated BP (120-139/ 80-89 mmHg, stage-1 hypertension (140-159/ 90-99 mmHg, and stage-2 hypertension (160-179/100-109 mmHg), respectively. According to the 2017 American College of Cardiology/American Heart Association criteria, maternal preconception elevated BP and hypertension were also significantly associated with an increased risk of PTB. Preconception systolic and diastolic BP showed a U-shaped (χ2 = 40.54; nonlinear P < 0.001) and linear (χ2 = 6.62; nonlinear P = 0.085) dose-response relationship with PTB, respectively. The association was modified by maternal age and preconception body mass index. These findings identify maternal preconception elevated BP and hypertension as a modifiable risk factor for PTB, providing evidence for future research studies, public health and clinical interventions.

Changes in the characteristics and outcomes of high-risk pregnant women who delivered prior to and after China's universal two-child policy: a real-world retrospective study, 2010-2021

BACKGROUND

In 2016, the "universal two-child" policy, allowing each couple to have two children, was introduced in China. The characteristic change of the long-term period after the implementation of the universal two-child policy was unclear. We studied trends in the obstetric characteristics and their potential impact on the rates of cesarean section and preterm birth in the era of China's universal two-child policy.

METHODS

A tertiary center-based study (2010-2021) retrospectively focused single high-risk pregnancies who delivered from the one-child policy period (OCP, 2010-2015) to the universal two-child policy period (TCP, 2016-2021). A total of 39, 016 pregnancies were enrolled. Maternal demographics, complications, delivery mode and obstetric outcomes were analyzed. Furthermore, logistic regression analysis was used to explore the association between the cesarean section rate, preterm birth and implementation of the universal two-child policy, adjusting maternal age, parity, and fetal distress.

RESULTS

Ultimately a total of 39,016 pregnant women met the criteria and were included in this analysis. The proportion of women with advanced maternal age (AMA) increased from 14.6% in the OCP to 31.6% in the TCP. The number of multiparous women increased 2-fold in the TCP. In addition, the overall rate of cesarean section significantly decreased over the policy change, regardless of maternal age, whereas the risk of preterm birth significantly increased in the TCP. Adjusting for maternal age, parity and fetal distress, the universal two-child policy showed a significantly favorable impact on the cesarean section rate (RR 0.745, 95%CI (0.714-0.777), P < 0.001). Compared to the OCP group, a higher increase in fetal distress and premature rupture of membranes (PROM) were observed in the TCP group. In pregnancies with AMA, there was no increase in the risk of postpartum hemorrhage, whereas more women who younger than 35 years old suffered from postpartum hemorrhage in TCP. The logistic regression model showed that the universal two-child policy was positively associated with the risk of postpartum hemorrhage (RR: 1.135, 95%CI: 1.025-1.257, P = 0.015).

CONCLUSIONS

After the implementation of the universal two-child policy in China, the rate of the cesarean section significantly decreased, especially for women under 35 years old. However, the overall risk of postpartum hemorrhage increased in women under 35 years old, while there was no change in women with AMA. Under the new population policy, the prevention of postpartum hemorrhage in the young women should not be neglected.

The impact of China's universal two-child policy on total, preterm, and multiple births: a nationwide interrupted time-series analysis

BACKGROUND

Although years have passed since the implementation of China's universal two-child policy, the effectiveness of this policy remains unclear. To address this knowledge gap, we, here, assessed the impact of the two-child policy on total live births, preterm births, and multiple live births.

METHODS

Data identifying pregnancies resulting in at least one live birth between April 1 2013 and December 31 2018 were collected from the Hospital Quality Monitoring System database. Using an interrupted time-series analysis, we estimated immediate level changes and long-term trends in total, preterm (birth before 37 weeks' gestation), and multiple live births that had occurred after July 2016, when the universal two-child policy had taken effect.

RESULTS

A total of 8,273,622 live births were reported during the study time frame. The number of live births (p = 0.277), preterm births (p = 0.052), and multiple births (p = 0.856) per month slightly increased immediately after July 2016, but these increases did not meet statistical significance. Further, all three outcomes showed a significant downward trend that lasted until the end of 2018 (p < 0.0001 for all). Among all live births, the percentage of preterm births remained stable (p = 0.101), while the percentage of multiple live births that were preterm significantly increased (trend change = 0.21% per month, 95% CI 0.14 to 0.28, p < 0.0001). The percentage of live multiple births among all live births significantly decreased (p for trend = 0.0039).

CONCLUSIONS

Overall, our data reveal a transient baby boom, as well as an increase in the proportion of live multiple births that were preterm, after China's two-child policy took effect. The latter should be noted by healthcare professionals due to the high risk of complications and special medical care required by preterm babies.

Neutrophil extracellular traps in adult diseases and neonatal bacterial infectious diseases: A review

Neutrophils, the most abundant type of white blood cells, are pivotal in fighting bacterial infections due to their immunological and anti-infection capabilities. In recent years, scientists have discovered a novel mechanism known as neutrophil extracellular traps, which are fibrous networks primarily released by neutrophils that combat bacterial infections. There is a growing interest in studying NETs and their role in human infectious diseases, particularly in neonates susceptible to bacterial infections. NETs and their components have been found in various samples from neonatal-infected patients, providing a new route for early diagnosis of neonatal infectious diseases. This paper aims to summarize the studies on NETs in adult diseases and mainly discuss NETs in neonatal sepsis, necrotizing enterocolitis, and purulent meningitis, to provide scientific evidence for early monitoring, diagnosis, and treatment of neonatal infections.

Effects of an online family-focused parenting support intervention on preterm infants' physical development and parents' sense of competence and care ability: A randomized controlled trial

BACKGROUND

Parenting of preterm infants presents unique challenges, particularly during their transition from hospital to home. Early discharge programs can assist parents during this critical period. However, the feasibility of delivering a family-focused online discharge program remains understudied.

OBJECTIVES

This study was conducted to investigate the impact of a family-focused online parenting support intervention on parents' sense of competence, depression, caregiving, social support, family functioning, and the weight and length of preterm infants.

METHODS

We conducted a single-blind, two-arm randomized controlled trial with a repeated-measures design. Participants were recruited from a specialized tertiary hospital in China between May and December 2022. Forty-five families were randomly assigned to the intervention group and 44 to the control group. The intervention included three components: (1) two one-hour group sessions and three 30-minute individual sessions of online parenting support; (2) two follow-up telephone calls (15-30 min each) post-discharge; and (3) access to online parenting resources. Primary outcomes included parenting sense of competence, parental care ability, and preterm infants' weight and length. Secondary outcomes included depression, social support, and family functioning. Measurements were taken at baseline, preterm infant discharge, one month post-discharge, and three months post-discharge. A generalized estimating equation model was employed based on the intention-to-treat principle for outcome comparison.

RESULTS

Parents in the intervention group showed significant improvements in parenting sense of competence (P < 0.001), parental care ability (P < 0.001), depression (P < 0.001), and social support (P = 0.002). However, no statistically significant differences were observed in preterm infants' weight and length, or in family functioning (P > 0.05).

CONCLUSIONS

Although the intervention did not affect preterm infants' outcomes, the positive enhancements in parenting sense of competence, care ability, depression, and social support indicate that online family-focused parenting support can effectively prepare parents for hospital discharge and the early transition period.

Association between exposure to outdoor artificial light at night and the risk of preterm birth

Background

This study aimed to investigate the association between outdoor artificial light at night (ALAN) exposure during pregnancy and the risk of preterm birth (PTB).

Methods

A retrospective case-control study was conducted, and data were collected from pregnant women residing in Beijing, China. The level of ALAN exposure during pregnancy was estimated using remote sensing satellite data. Propensity score matching was utilized to match the control group. Logistic and multivariate linear regression were used to analyze the association between ALAN and the risk of PTB. The odds ratio (OR) and partial regression coefficient (β) with 95% confidence interval (CI) were utilized to assess the association.

Results

A total of 2,850 pregnant women were enrolled in this study. ALAN (nW/cm2/sr) exposure was higher in the PTB group than in the control group during first trimester (mean ± standard deviation: 25.30 ± 17.91 vs. 17.56 ± 14.74, p < 0.001) and second trimester (27.07 ± 18.10 vs. 21.93 ± 16.08, p < 0.001). A negative association was found between ALAN exposure and gestation day in the first (β = -0.151, 95%CI: -0.217 to -0.085, p < 0.001) and second trimesters (β = -0.077, 95%CI: -0.139 to -0.015, p = 0.015). ALAN was identified as a risk factor for PTB during the first trimester (OR = 1.032, 95%CI: 1.025-1.040, p < 0.001) and the second trimester (OR = 1.018, 95%CI: 1.011-1.025, p < 0.001), while no significant association was observed in the third trimester.

Conclusion

Our study suggesting that exposure to outdoor ALAN, especially during first and second trimester, was associated with the risk of PTB. These findings highlight the potential impact of ALAN on pregnancy health and offer new insights into the risk of PTB.

The dynamic nexus: exploring the interplay of BMI before, during, and after pregnancy with Metabolic Syndrome (MetS) risk in Chinese lactating women

BACKGROUND AND AIM

The health implications of BMI and MetS in lactating women are significant. This study aims to investigate the relationship between risk of Mets in lactation and BMI in four stages: pre-pregnancy, prenatal period, 42 days postpartum, and current lactation.

METHODS AND RESULTS

A total of 1870 Lactating Women within 2 years after delivery were included from "China Child and Lactating Mother Nutrition Health Surveillance (2016-2017)". Logistic regression model and Restricted cubic spline (RCS) were used to estimate the relationship between BMI and risk of MetS. ROC analysis was used to determine the threshold for the risk of MetS. Chain mediating effect analysis was used to verify the mediating effect. BMI of MetS group in all stages were higher than non-MetS group (P < 0.0001). There were significant positive correlations between BMI in each stage and ORs of MetS during lactation (P < 0.05). The best cut-off values for BMI in the four stages were 23.47, 30.49, 26.04 and 25.47 kg/m2. The non-linear spline test at BMI in 42 days postpartum, current and MetS in lactation was statistically significant (P non-linear = 0.0223, 0.0003). The mediation effect of all chains have to work through lactation BMI. The total indirect effect accounted for 80.95% of the total effect.

CONCLUSIONS

The risk of MetS in lactating women is due to a high BMI base before pregnancy and postpartum. High BMI in all stages of pregnancy and postpartum were risk factors for MetS in lactation. BMI during lactation plays a key role in the risk of MetS.

Safety of hepatitis E vaccination for pregnancy: a post-hoc analysis of a randomized, double-blind, controlled phase 3 clinical trial

Special attention has been paid to Hepatitis E (HE) prophylaxis for pregnant women due to poor prognosis of HE in this population. We conducted a post-hoc analysis based on the randomized, double-blind, HE vaccine (Hecolin)-controlled phase 3 clinical trial of human papillomavirus (HPV) vaccine (Cecolin) conducted in China. Eligible healthy women aged 18-45 years were randomly assigned to receive three doses of Cecolin or Hecolin and were followed up for 66 months. All the pregnancy-related events throughout the study period were closely followed up. The incidences of adverse events, pregnancy complications, and adverse pregnancy outcomes were analysed based on the vaccine group, maternal age, and interval between vaccination and pregnancy onset. During the study period, 1263 Hecolin receivers and 1260 Cecolin receivers reported 1684 and 1660 pregnancies, respectively. The participants in the two vaccine groups showed similar maternal and neonatal safety profiles, regardless of maternal age. Among the 140 women who were inadvertently vaccinated during pregnancy, the incidences of adverse reactions had no statistical difference between the two groups (31.8% vs 35.1%, p = 0.6782). The proximal exposure to HE vaccination was not associated with a significantly higher risk of abnormal foetal loss (OR 0.80, 95% CI 0.38-1.70) or neonatal abnormality (OR 2.46, 95% CI 0.74-8.18) than that to HPV vaccination, as did distal exposure. Significant difference was not noted between pregnancies with proximal and distal exposure to HE vaccination. Conclusively, HE vaccination during or shortly before pregnancy is not associated with increased risks for both the pregnant women and pregnancy outcomes.

The effects of different endometrial preparation regimens on pregnancy outcomes in frozen-thawed embryo transfer cycles: a prospective randomized controlled study

OBJECTIVE

An increasing number of research have emerged to compare the pregnancy outcomes between the natural cycle and the hormone replacement therapy (HRT) cycle in preparing the endometrium for frozen-thawed embryo transfer (FET), but the results are controversial. This prospective randomized controlled study was hence designed to obtain more solid evidence.

MATERIALS AND METHODS

In this study, patients with regular menstrual cycle length (21-35 days) who underwent FET between January 2010 to December 2017 were recruited for this study. Upon further filtering with the selection criteria of patients being, a total of 405 patients were recruited and randomized. Finally, analysis was performed on 384 patients: 178 belonged to the natural cycle group whereas the remaining 206 were in the HRT group. The primary outcome was live birth rate, while the secondary outcomes were implantation rate, clinical pregnancy rate, early miscarriage rate, late miscarriage rate, multiple birth rate and low birth weight rate.

RESULTS

The live birth rate (37.6% vs 30.1%, p = 0.119) of natural cycle group were higher than those of the hormone replacement therapy group, although the difference was not significant. The secondary outcomes were not found to differ significantly between the two groups. Nonetheless, the endometrium was found to be thicker in the natural cycle group (10.75 mm) than the HRT group (9.00 mm) (p < 0.001).

CONCLUSION

No significant differences were observed between the pregnancy outcomes of the natural cycle group and the HRT group which comprised of patients with regular menstrual cycle length.

[Therapeutic efficacy of volume-guaranteed high frequency oscillation ventilation on respiratory failure in preterm infants with a gestational age of 28-34 weeks: a prospective randomized controlled study]

OBJECTIVES

To investigate the therapeutic efficacy of volume-guaranteed high frequency oscillation ventilation (HFOV-VG) versus conventional mechanical ventilation (CMV) in the treatment of preterm infants with respiratory failure.

METHODS

A prospective study was conducted on 112 preterm infants with respiratory failure (a gestational age of 28-34 weeks) who were admitted to the Department of Neonatology, Jiangyin Hospital Affiliated to Medical School of Southeast University, from October 2018 to December 2022. The infants were randomly divided into an HFOV-VG group (44 infants) and a CMV group (68 infants) using the coin tossing method based on the mode of mechanical ventilation. The therapeutic efficacy was compared between the two groups.

RESULTS

After 24 hours of treatment, both the HFOV-VG and CMV groups showed significant improvements in arterial blood pH, partial pressure of oxygen, partial pressure of carbon dioxide, and partial pressure of oxygen/fractional concentration of inspired oxygen ratio (P<0.05), and the HFOV-VG group had better improvements than the CMV group (P<0.05). There were no significant differences between the two groups in the incidence rate of complications, 28-day mortality rate, and length of hospital stay (P>0.05), but the HFOV-VG group had a significantly shorter duration of invasive mechanical ventilation than the CMV group (P<0.05). The follow-up at the corrected age of 6 months showed that there were no significant differences between the two groups in the scores of developmental quotient, gross motor function, fine motor function, adaptive ability, language, and social behavior in the Pediatric Neuropsychological Development Scale (P>0.05).

CONCLUSIONS

Compared with CMV mode, HFOV-VG mode improves partial pressure of oxygen and promotes carbon dioxide elimination, thereby enhancing oxygenation and shortening the duration of mechanical ventilation in preterm infants with respiratory failure, while it has no significant impact on short-term neurobehavioral development in these infants.

Factors associated with high exclusive breastfeeding rates among preterm infants under 34 weeks of gestation in Da Nang, Vietnam: A retrospective cohort study

Background

Preterm infants have higher mortality than full-term infants. While breastfeeding dramatically reduces preterm death, it is limited by biological and practice barriers, particularly for babies born before 34 weeks gestational age. Da Nang Hospital for Women and Children developed a quality improvement approach to improve breastfeeding of preterm infants by strengthening feeding support, non-separation, and kangaroo mother care (KMC).

Methods

To determine breastfeeding outcomes following discharge and explore factors associated with improved feeding, mothers of infants under 34 weeks gestational age born October 2021 to March 2022 and discharged alive were interviewed at six months and their medical records were reviewed.

Results

Out of 104 preterm infants included, all were exclusively breastfed at discharge and one month, 86.5% at three months, and 63.5% at six months; 47.1% received immediate skin-to-skin contact, 31.7% immediate and continuous KMC, and the remaining 68.3% continuous KMC beginning at a median of three days. Exclusive breastfeeding at six months was associated with the mother antenatally seeking breastfeeding information (odds ratio (OR) = 14.5; 95% confidence interval (CI) = 1.2-173.6), avoiding bottle-feeding at home (OR = 7.7; 95% CI = 1.7-33.7) and reduced with each day delay between birth and full breastfeeding (OR = 0.8; 95% CI = 0.6-0.9).

Conclusions

Hospital environments that limit mother-baby separations and feeding delays, including rooming-in of mothers and infants, KMC, and breastfeeding support from birth, enabled 100% of preterm infants born before 34 weeks gestational age to breastfeed exclusively with continued rates higher than previously reported. Addressing antenatal and post-natal factors limiting practice can further improve longer-term breastfeeding outcomes. The approach can be adapted to achieve high exclusive breastfeeding rates, regardless of gestational age.

A nomogram for predicting death for infants born at a gestational age of <28 weeks: a population-based analysis in 18 neonatal intensive care units in northern China

Background

In China, the number of preterm infants is the second largest globally. Compared with those in developed countries, the mortality rate and proportion of treatment abandonment for extremely preterm infants (EPIs) are higher in China. It would be valuable to conduct a multicenter study and develop predictive models for the mortality risk. This study aimed to identify a predictive model among EPIs who received complete care in northern China in recent years.

Methods

This study included EPIs admitted to eighteen neonatal intensive care units (NICUs) within 72 hours of birth for receiving complete care in northern China between January 1, 2015, and December 31, 2018. Infants were randomly assigned into a training dataset and validation dataset with a ratio of 7:3. Univariate Cox regression analysis and multiple regression analysis were used to select the predictive factors and to construct the best-fitting model for predicting in-hospital mortality. A nomogram was plotted and the discrimination ability was tested by an area under the receiver operating characteristic curve (AUROC). The calibration ability was tested by a calibration curve along with the Hosmer-Lemeshow (HL) test. In addition, the clinical effectiveness was examined by decision curve analysis (DCA).

Results

A total of 568 EPIs were included and divided into the training dataset and validation dataset. Seven variables [birth weight (BW), being inborn, chest compression in the delivery room (DR), severe respiratory distress syndrome, pulmonary hemorrhage, invasive mechanical ventilation, and shock] were selected to establish a predictive nomogram. The AUROC values for the training and validation datasets were 0.863 [95% confidence interval (CI): 0.813-0.914] and 0.886 (95% CI: 0.827-0.945), respectively. The calibration plots and HL test indicated satisfactory accuracy. The DCA demonstrated that positive net benefits were shown when the threshold was >0.6.

Conclusions

A nomogram based on seven risk factors is developed in this study and might help clinicians identify EPIs with risk of poor prognoses early.

Association between light rare earth elements in maternal plasma and the risk of spontaneous preterm birth: a nested case-control study from the Beijing birth cohort study

BACKGROUND

Parental exposure to rare earth elements (REEs) could increase the risk of premature rupture of membranes, a major cause of spontaneous preterm birth (SPB). In addition, different subtypes of SPB, such as spontaneous preterm labor (SPL) and preterm premature rupture of membranes (PPROM), may have different susceptibility to environmental exposure. Therefore, we investigated the potential associations between REE exposure in different trimesters and SPB and its subtypes.

METHODS

A nested case-control study was performed. We included 244 women with SPB as cases and 244 women with full-term delivery as controls. The plasma concentrations of light REEs were measured in the first and third trimesters. Logistic regression was used to analyze the associations between single REE levels and SPB, and Bayesian kernel machine regression (BKMR) was used to analyze the mixed-exposure effect.

RESULTS

Exposure to light REEs was associated with SPB and its subtypes only in the third trimester. Specifically, the intermediate- and highest-tertile concentration groups of La and the highest-tertile concentration group of Sm were associated with an increased risk of SPL, with adjusted odds ratios (AORs) of 2.00 (95% CIs: 1.07-3.75), 1.87 (95% CIs: 1.01-3.44), and 1.82 (95% CIs: 1.00-3.30), respectively. The highest-tertile concentration group of Pr was associated with an increased risk of PPROM, with an AOR of 1.69 (95% CIs: 1.00-2.85). Similar results were also found in BKMR models.

CONCLUSIONS

La and Sm levels in plasma may be associated with the risk of SPL, and Pr levels in plasma may be associated with the risk of PPROM.