Association of interpregnancy interval and risk of adverse pregnancy outcomes in woman by different previous gestational ages.

Background: With an increasing proportion of multiparas, proper interpregnancy intervals (IPIs) are urgently needed. However, the association between IPIs and adverse perinatal outcomes has always been debated. This study aimed to explore the association between IPIs and adverse outcomes in different fertility policy periods and for different previous gestational ages.

Non-invasive prenatal testing for the detection of trisomies 21, 18, and 13 in pregnant women with various clinical indications: A multicenter observational study of 1,854,148 women in China.

Objective: This study aimed to evaluate the performance of noninvasive prenatal testing (NIPT) for detecting three common trisomies (T21, T18, and T13) in pregnant women with diverse clinical indications.

Methods: Frequencies of NIPT, of high chance of having one of the three trisomies, and of confirmed trisomies were determined for women with each of seven clinical indications in a national cross-sectional survey of approximately 300 prenatal diagnosis centers. Data were collected for the period from October 1, 2016 to September 30, 2018 using the Prenatal Diagnosis Technology Management On-line Information System.

Characteristics and fetal outcomes of pregnant women with hypertensive disorders in China: a 9-year national hospital-based cohort study.

Background: Hypertensive disorders of pregnancy (HDP) are a growing concern and a challenge for maternity care providers as the prevalence of hypertension continues to increase. However, optimal management of HDP is unclear. Therefore, we aimed to explore the differences in adverse fetal outcomes among women with different subtypes of HDP and different blood pressure (BP) levels, to provide evidence-based management of HDP.

Interrupted-time-series analysis of the immediate impact of COVID-19 mitigation measures on preterm birth in China.

Preliminary evidence from China and other countries has suggested that coronavirus disease 2019 (COVID-19) mitigation measures have caused a decline in preterm births, but evidence is conflicting. Utilising a national representative data of 11,714,947 pregnant women in China, we explored the immediate changes in preterm birth rates during the COVID-19 mitigation period using an interrupted-time-series analysis. We defined the period prior to February 1, 2020 as the baseline, followed by the COVID-19 mitigation stage.

Temporal trends and adverse perinatal outcomes of twin pregnancies at differing gestational ages: an observational study from China between 2012-2020.

Background: With the development of assisted reproductive technology, the twinning rate in China has been increasing. However, little is known about twinning from 2014 onwards. In addition, previous studies analysing optimal gestational times have rarely considered maternal health conditions.

Geographical disparities in infant mortality in the rural areas of China: a descriptive study, 2010-2018.

Background: The infant mortality rate (IMR) is considered a basic measure of public health for countries around the world. The specific aim of our study was to provide an updated description of infant mortality rate among different regions in rural China, and assess the trends and causes of the IMR geographical disparities.

Methods: Data were collected from China's Under-5 Child Mortality Surveillance System(U5CMSS).

Incidence, trends and risk factors for obstetric massive blood transfusion in China from 2012 to 2019: an observational study.

Objectives: This study aims to use the high-quality national monitoring data from the China's National Maternal Near Miss Surveillance System (NMNMSS) to ascertain the incidence, trends and risk factors of obstetric massive blood transfusion (MBT) from 2012 to 2019 in China and determine its clinical outcomes.

Settings: Observational study of hospitalised pregnancies who had given birth or ended their pregnancy among member hospitals of NMNMSS.

Participants: 11 667 406 women were included in this study.

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

Background: Preterm birth rates have increased significantly worldwide over the past decade. Few epidemiological studies on the incidence of preterm birth and temporal trends are available in China. This study used national monitoring data from China's National Maternal Near Miss Surveillance System (NMNMSS) to estimate the rate of preterm birth and trends between 2012 and 2018 in China and to assess risk factors associated with preterm birth.

Characteristics and adverse outcomes of Chinese adolescent pregnancies between 2012 and 2019.

We aimed to describe the characteristics of adolescent pregnancy, determine its effect on adverse maternal and perinatal outcomes and explore whether that association varies with gestational age with the goal of proposing specific recommendations for adolescent health in China. This study included 2,366,559 women aged 10-24 years who had singleton pregnancies between 2012 and 2019 at 438 hospitals. Adolescent pregnancy was defined as younger than 20 years of age.

The trends and associated adverse maternal and perinatal outcomes of labour neuraxial analgesia among vaginal deliveries in China between 2012 and 2019: a real-world observational evidence.

Background: There is a lack of national report of the labour neuraxial analgesia (NA) rates in China in recent years, especially after the national promotion policy. The adverse maternal and perinatal outcomes associated with NA in China are also unknown. The aim of this study is to estimate the trends of NA rates from 2012 to 2019, to evaluate the effect of national policy on promoting NA and to identify the association between NA and adverse outcomes in China.

Apgar score and neonatal mortality in China: an observational study from a national surveillance system.

Background: To examine the association between the Apgar score and neonatal mortality over gestational age in China and to explore whether this association changed when Apgar scores were combined at 1 and 5 min.

Methods: Data for all singleton live births collected from 438 hospitals between 2012 and 2016 were used in this study. Poisson regression with a robust variance estimator adjusted for a complete set of confounders was used to describe the strength of the association between the Apgar score and neonatal mortality.

Provincial-level outcomes of China's 'Reducing maternal mortality and eliminating neonatal tetanus' program.

To determine whether the nationwide program 'Reducing maternal mortality and eliminating neonatal tetanus' contributed to the rapid decline in China's maternal mortality ratio (MMR) and neonatal tetanus elimination by enhancing hospital delivery, we compared MMR and neonatal tetanus incidence rate (NTR) reductions by province from 2000 to 2013. The difference-in-difference method was used to analyze the program effect. Long-term effects were analyzed relative to MMR and NTR in 2000 and 2002, respectively, while short-term effects in a given year were analyzed relative to MMR and NTR in the preceding year.

Spatiotemporal trends and ecological determinants in maternal mortality ratios in 2,205 Chinese counties, 2010-2013: A Bayesian modelling analysis.

Background: As one of its Millennium Development Goals (MDGs), China has achieved a dramatic reduction in the maternal mortality ratio (MMR), although a distinct spatial heterogeneity still persists. Evidence of the quantitative effects of determinants on MMR in China is limited. A better understanding of the spatiotemporal heterogeneity and quantifying determinants of the MMR would support evidence-based policymaking to sustainably reduce the MMR in China and other developing areas worldwide.

The national maternal near miss surveillance in China: A facility-based surveillance system covered 30 provinces.

To introduce the National Maternal Near Miss Surveillance System (NMNMSS) in detail and to report the composition of maternal near miss (MNM) in China.The NMNMSS was established by the National Health Commission at the end of 2010, covered over 400 health facilities from 30 provinces in China. The NMNMSS was designed to collect individual information for every pregnant woman admitted to obstetric department in the sampled health facilities.

Prevalence of postterm births and associated maternal risk factors in China: data from over 6 million births at health facilities between 2012 and 2016.

Postterm births are associated with an increased risk of adverse perinatal outcomes, but few studies have investigated the epidemiological characteristics of postterm births. We aimed to estimate the prevalence of postterm births and examine the potential association between maternal sociodemographic and obstetric characteristics and postterm births. Data were collected from China's National Maternal Near Miss Surveillance System, 2012-2016.

Maternal mortality ratios in 2852 Chinese counties, 1996-2015, and achievement of Millennium Development Goal 5 in China: a subnational analysis of the Global Burden of Disease Study 2016.

Background: As one of only a handful of countries that have achieved both Millennium Development Goals (MDGs) 4 and 5, China has substantially lowered maternal mortality in the past two decades. Little is known, however, about the levels and trends of maternal mortality at the county level in China.

Methods: Using a national registration system of maternal mortality at the county level, we estimated the maternal mortality ratios for 2852 counties in China between 1996 and 2015.

Prior caesarean section and likelihood of vaginal birth, 2012-2016, China.

Objective: To examine the trends and safety of vaginal birth after caesarean section around the period of the one-child policy relaxation in China.

Methods: We used data from China's National Maternal Near Miss Surveillance System between 2012 and 2016. To examine trends in vaginal birth after caesarean section, we used Poisson regression with a robust variance estimator.

Relaxation of the one child policy and trends in caesarean section rates and birth outcomes in China between 2012 and 2016: observational study of nearly seven million health facility births.

Objective: To examine how the relaxation of the one child policy and policies to reduce caesarean section rates might have affected trends over time in caesarean section rates and perinatal and pregnancy related mortality in China.

Design: Observational study.

Setting: China's National Maternal Near Miss Surveillance System (NMNMSS).

The Sex Ratio at Birth for 5,338,853 Deliveries in China from 2012 to 2015: A Facility-Based Study.

Objective: The accuracy of a population-based sex ratio at birth (SRB) in China has long been questioned. To depict a more accurate profile, the present study used data from a national surveillance system for health facility births to explore the characteristics of SRB in China.

Methods: Data from China's National Maternal Near Miss Surveillance System between 2012 and 2015 were used.

Low birthweight in China: evidence from 441 health facilities between 2012 and 2014.

Objective: This study aimed to identify new evidence about the burden and risk factors of low birthweight (LBW) in China using national facility-based data.

Methods: The association between sociodemographic and obstetric characteristics and LBW was examined using a multilevel model, taking into account the clustering of livebirths within hospitals and multiple gestations per woman.

Results: There were 3 915 965 deliveries and 235 247 cases born with LBW, producing a LBW rate of 5.

Hypoxia-inducible factor-1α mediates the toll-like receptor 4 signaling pathway leading to anti-tumor effects in human hepatocellular carcinoma cells under hypoxic conditions.

Hypoxia-inducible factor-1α (HIF-1α) and toll-like receptor 4 (TLR4) are involved in numerous mechanisms of cancer biology, including cell proliferation and survival; however the interaction of the two factors under hypoxic conditions remains unclear. The present study investigated the mechanism that results in the suppression of tumor cell growth and cellular functions when HIF-1α is silenced. In the present study, the human hepatocellular carcinoma HepG2 cell line was transfected with short hairpin RNA (shRNA) against HIF-1α and cultured under hypoxic conditions (1% O for 24 h).

Sociodemographic and obstetric characteristics of stillbirths in China: a census of nearly 4 million health facility births between 2012 and 2014.

Background: Very little is known about the burden and determinants of stillbirths in China. We used data from a national surveillance system for health facility births to compute a stillbirth rate representative of all facility births in China and to explore sociodemographic and obstetric factors associated with variation in the stillbirth rate.

Methods: We used data from China's National Maternal Near Miss Surveillance System between Jan 1, 2012, and Dec 31, 2014, which covers 441 hospitals in 326 urban districts and rural counties.

A novel missense NMNAT1 mutation identified in a consanguineous family with Leber congenital amaurosis by targeted next generation sequencing.

Leber congenital amaurosis is the earliest onset and most severe inherited retinal dystrophy. Mutations in 21 genes have been identified to be responsible for LCA. To detect the causative variants, we performed targeted next generation sequencing in two affected siblings of a consanguineous Chinese family with suspected LCA.

Geographic and urban-rural disparities in the total prevalence of neural tube defects and their subtypes during 2006-2008 in China: a study using the hospital-based birth defects surveillance system.

Background: Previous reports on the prevalence of neural tube defects (NTDs) in China did not include cases of NTDs that were less than 28 weeks of gestational age (GA) and hence did not accurately reflect the total prevalence of NTDs or the geographic and urban-rural disparities in their prevalence. This article includes cases of NTDs that were less than 28 weeks of GA.

Methods: Data used in this study were collected from 2006 to 2008 using a nationwide hospital-based registry, the Chinese Birth Defects Monitoring Network.