Juan Liang

Time trends in oral clefts in Chinese newborns: Data from the Chinese National Birth Defects Monitoring Network

BACKGROUND Although the prevalence of oral clefts in China is among the highest in countries worldwide, little is known about its descriptive epidemiology. METHODS Data used in this study were collected from 1996 to 2005 using the nationwide hospital-based registry, the Chinese Birth Defects Monitoring Network. A total of 4,891,472 newborns (live or still births with 28 weeks of gestation or more) delivered in member hospitals were assessed for birth defects within 7 days following birth. RESULTS The prevalence of nonsyndromic, syndromic, and overall clefts was 14.23, 2.40, and 16.63 per 10,000, respectively. An upward time trend in the prevalence of nonsyndromic cleft palate and nonsyndromic cleft lip was detected. Cleft lip with or without cleft palate showed a different pattern by gender, urban-rural classification, and geographic location when compared to cleft palate, particularly for nonsyndromic cases. Maternal age was associated with prevalence of all oral clefts. Neonates with oral clefts had increased rates of mortality. CONCLUSIONS The observed complex patterns of prevalence of oral clefts from the Chinese national birth defects registry indicate that oral cleft subtypes by either cleft location or syndromic status should be considered in the development of intervention measures and in future analytical studies.

Birth defects surveillance in China.

BackgroundBirth defects are a global public health problem because of their large contribution to infant mortalities and disabilities. It is estimated that 4%–6% of Chinese newborns are affected by birth defects every year. Surveillance is a basic approach to understanding the occurrence and associated factors of birth defects. The Ministry of Health of China initiated a national hospital-based birth defects monitoring system 20 years ago. Nearly every province in this country has established its own surveillance system in the past. The authors reviewed the result of the monitoring system at different administrative levels in China.Data sourcesAvailable publications on the surveillance of birth defects and data from national and provincial birth defects surveillance systems were reviewed to evaluate the effectiveness of the surveillance systems.ResultsAccording to the 2009 data, the national hospital-based birth defects surveillance system monitored over 1.3 million births, which accounted for more than 8% of births in China. In addition, 30 provincial hospital-based surveillance programs covered a birth population of more than 3.6 million (22% of births in China). Great achievements have been made in terms of case ascertainment, data quality control, and online reporting. But the surveillance systems in China still have some limitations. A short ascertainment period may miss some internal anomalies, inherited metabolic diseases, and malformed fetus aborted before the 28th gestational week. Discrepancies in antenatal or postnatal diagnosis of birth defects between surveillance institutes may affect the detection rate and introduce biases. Absence of baseline data and lack of integrated database systems limit the application of surveillance data to etiological studies and affect the process of decision-making.ConclusionsThe surveillance system for birth defects is prerequisite to propose, conduct and assess any interventions for the disease. To meet the need of study and prevention of birth defects, measures should be taken to improve the national and provincial birth defects surveillance systems in China.

Maternal mortality in China, 1996-2005

To analyze the trend in maternal mortality ratio (MMR), characteristics and causes of maternal deaths, and factors influencing the MMR in China between 1996 and 2005.

Mortality rate for children under 5 years of age in China from 1996 to 2006

OBJECTIVES To study the change in mortality rate for children under 5 years of age in China over the past decade, and to evaluate Chinas progress in achieving Millennium Development Goal 4. STUDY DESIGN Population-based descriptive study. METHODS A population-based survey was conducted through a nationwide multi-level surveillance network. The mortality rate and the leading causes of death for children under 5 years of age were analysed. RESULTS The mortality rate for children under 5 years of age in China dropped by 54.2% between 1996 and 2006 (from 45.0 per 1000 livebirths to 20.6). During this period, deaths due to pneumonia and diarrhoea dropped by 69.4% and 69.7%, respectively. The proportion of deaths due to pneumonia dropped from 23.4% in 1996 to 15.6% in 2006, and the proportion of deaths due to diarrhoea dropped from 5.6% in 1996 to 3.7% in 2006. CONCLUSION The mortality rate for children under 5 years of age in China dropped remarkably from 1996 to 2006. This reduction was mainly due to a significant decrease in deaths due to pneumonia and diarrhoea. Based on the survey results, China should be able to achieve Millennium Development Goal 4.

Preventable maternal mortality: Geographic/rural-urban differences and associated factors from the population-based maternal mortality surveillance system in China

BackgroundMost maternal deaths in developing countries can be prevented. China is among the 13 countries with the most maternal deaths; however, there has been a marked decrease in the maternal mortality ratio (MMR) over the last 3 decades. Chinas reduction in the MMR has contributed significantly to the global decline of the MMR. This study examined the geographic and rural-urban differences, time trends and related factors in preventable maternal deaths in China during 1996-2005, with the aim of providing reliable evidence for effective interventions.MethodsData were retrieved from the population-based maternal mortality surveillance system in China. Each death was reviewed by three committees to determine whether it was avoidable. The preventable maternal mortality ratio (PMMR), the ratios of PMMR (risk ratio, RR) and 95% confidence intervals (CI) were used to analyze regional disparities (coastal, inland and remote regions) and rural-urban variations. Time trends in the MMR, along with underlying causes and associated factors of death, were also analysed.ResultsOverall, 86.1% of maternal mortality was preventable. The RR of preventable maternal mortality adjusted by region was 2.79 (95% CI 2.42-3.21) and 2.38 (95% CI: 2.01-2.81) in rural areas compared to urban areas during the 1996-2000 and 2001-2005 periods, respectively. Meanwhile, the RR was the highest in remote areas, which was 4.80(95%CI: 4.10-5.61) and 4.74(95%CI: 3.86-5.83) times as much as that of coastal areas. Obstetric haemorrhage accounted for over 50% of preventable deaths during the 2001-2005 period. Insufficient information about pregnancy among women in remote areas and out-of-date knowledge and skills of health professionals and substandard obstetric services in coastal regions were the factors frequently associated with MMR.ConclusionsPreventable maternal mortality and the distribution of its associated factors in China revealed obvious regional differences. The PMMR was higher in underdeveloped regions. In future interventions in remote and inland areas, more emphasis should be placed on improving womens ability to utilize healthcare services, enhancing the service capability of health institutions, and increasing the accessibility of obstetric services. These approaches will effectively lower PMMR in those regions and narrow the gap among the different regions.

Geographical disparities of infant mortality in rural China.

Objective The purpose of the study was to investigate the trends and causes of regional disparities of infant mortality rate (IMR) in rural China from 1996 to 2008. Design A population-based, longitudinal study. Setting The national child mortality surveillance network. Population Population of the 79 surveillance counties. Main outcome measure IMR, leading causes of infant death and the RR of IMR. Results The IMR in coastal, inland and remote regions declined by 72.4%, 62.9% and 58.2%, respectively, from 1996 to 2008. Compared with the coastal region, the RR of IMR were 1.7 (95% CI 1.6 to 1.9), 1.9 (95% CI 1.7 to 2.0) and 1.8 (95% CI 1.6 to 2.0) for inland region and 2.6 (95% CI 2.4 to 2.7), 3.2 (95% CI 3.0 to 3.5) and 3.1 (95% CI 2.7 to 3.4) for the remote region during 1996–2000, 2001–2005 and 2006–2008, respectively. The regional disparities existed for both male and female IMRs. The postneonatal mortality showed the highest regional disparities. Pneumonia, birth asphyxia, prematurity/low birth weight, injuries and diarrhoea were the main contributors to the regional disparities. There were significantly more infants who did not seek healthcare services before death in the remote region relative to the inland and coastal regions. Conclusion The results indicated persistent existence of regional disparities in IMR in rural China. It is worth noting that regional disparities in IMR increased in the remote and coastal regions during 2001–2005 in rural China. These disparities remained unchanged during 2006–2008. The results indicate that strategies to reduce mortality caused by pneumonia, birth asphyxia and diarrhoea are keys to reducing IMR.

The changes in maternal mortality in 1000 counties in mid-western China by a government-initiated intervention.

Background Since 2000, the Chinese government has implemented an intervention program to reduce maternal mortality and eliminate neonatal tetanus in accordance with the Millennium Development Goals 5. To assess the effectiveness of this intervention program, we analyzed the level, trend and reasons defining the maternal mortality ratio (MMR) in the 1,000 priority counties before and after implementation of the intervention between 1999 and 2007. Methodology/Principal Findings The data was obtained from the National Maternal and Child Health Routine Reporting System. The intervention included providing basic and emergency obstetric equipment and supplies to local medical hospitals, and also included providing professional training to local obstetric doctors, development of obstetric emergency centers and “green channel” express referral networks, reducing or waiving the cost of hospital delivery, and conducting community health education. Based on the initiation time of the intervention and the level of poverty, 1,000 counties, containing a total population of 300 million, were categorized into three groups. MMR significantly decreased by about 50%, with an average reduction rate of 9.24%, 16.06%, and 18.61% per year in the three county groups, respectively. The hospital delivery rate significantly increased. Obstetric hemorrhage was the leading cause of maternal deaths and significantly declined, with an average decrease in the MMR of 11.25%, 18.03%, and 24.90% per year, respectively. The magnitude of the MMR, the average reduction rate of the MMR, and the occurrence of the leading causes of death were closely associated with the percentage of poverty. Conclusions/Significance The intervention program implemented by the Chinese government has significantly reduced the MMR in mid-western China, suggesting that well-targeted interventions could be an efficient strategy to reducing MMR in resource-poor areas. Reduction of the MMR not only depends on conducting proven interventions, but also relies on economic development in rural areas with a high burden of maternal death.

Time trends and geographic variations in the prevalence of hypospadias in China

BACKGROUND Little is known about the main epidemiologic characteristics of hypospadias prevalence in China. We investigated the time trends and geographic variations in the prevalence of hypospadias in China from 1996 to 2008. METHODS Data were retrieved from the hospital-based birth defects monitoring system in China from 1996 to 2008. We used prevalence ratios (PRs) to describe the difference in prevalence of hypospadias between urban and rural areas, as well as among different regions. Poisson regression was used to explore the long time trend for the prevalence of hypospadias and its regional disparity. RESULTS The prevalences of hypospadias for isolated anomalies, multiple anomalies, and overall cases were 7.64, 1.39, and 9.03 per 10,000 births, respectively. The national PRs (urban vs. rural) of hypospadias for overall and isolated cases were 1.25 (95% confidence interval [CI], 1.16-1.35) and 1.27 (95% CI, 1.17-1.38), respectively. The highest prevalence (12.10 per 10,000 births) was observed in the eastern region. A positive correlation was found between the prevalence of hypospadias and maternal age (p < 0.01). The average annual increase of 7.43% (95% CI, 5.52-9.38%) was observed in the overall prevalence of hypospadias in China; it was 5.28% (95% CI, 4.16-6.43%) in urban areas, 9.79% (95% CI, 7.72-11.90%) in rural areas, 9.08% (95% CI, 6.36-11.86%) in the eastern region, 4.76% (95% CI, 2.93-6.62%) in the central region, and 6.57% (95% CI, 4.44-8.74%) in the western region. CONCLUSION The increasing trends and differences of hypospadias prevalence by urban-rural classification and geographical location suggest that environmental exposure and maternal age might have a critical role in the development of hypospadias.

Neonatal mortality due to preterm birth at 28-36 weeks gestation in China 2003-2008.

Almost all (99%) neonatal deaths occur in developing countries, where the progress in reducing neonatal mortality rates (NMR) has been small; the Millennium Development Goal for child survival cannot be met if this situation continues. China is among the 10 countries that have the largest numbers of neonatal deaths. In order to provide effective interventions to reduce the national NMR for government policy makers, we analyse the trends, causes and characteristics of the neonatal deaths of preterm babies in different regions of China during the period 2003-2008. The data for this retrospective study were retrieved from the population-based Maternal and Child Health Surveillance System of China. The Cochran-Armitage trend test was used to analyse the trend of NMRs due to immaturity. The national NMR due to immaturity has decreased by 38.7% in 6 years. However, the proportion of preterm births among the causes of neonatal death has increased significantly from 33.6% in 2003 to 40.9% in 2008. The relative risk of neonatal death among preterm babies has shown significant regional disparity. In 2008, the adjusted relative risk was 1.30 [95% confidence interval (CI) 0.95, 1.78] in the inland regions and 2.37 [95% CI 1.56, 3.60] in the remote regions, both compared with the coastal regions. The proportion of neonatal deaths with a gestational age <32 weeks or a birthweight <1500 g was highest among the coastal regions. Most neonatal deaths of preterm babies in remote areas were born at home and were not treated before death. Our study suggests that preterm birth is the leading cause of neonatal death in China and neonatal mortality due to immaturity displayed regional differences. The Chinese government should implement major effective strategies for reducing the mortality of preterm infants to further decrease the total NMR. Priority interventions should be region-specific, depending on the availability of economic and health care resources.

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

BackgroundPrevious 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.MethodsData used in this study were collected from 2006 to 2008 using a nationwide hospital-based registry, the Chinese Birth Defects Monitoring Network. The total prevalence ratio (PR) of NTDs and their subtypes, the ratios of PR (PRR), and 95% confidence intervals (CI) were used to analyse geographic disparities at both the regional (north, south) and provincial levels and to analyse disparities between rural and urban areas.ResultsOverall, the total PR of NTDs was 14.0 per 10,000 births. The PRR of NTDs of rural women between the north and south region was 2.26 (95% CI: 2.04-2.52), which was much higher than that of urban women (PRR: 1.56, 95% CI: 1.41-1.72). The three subtypes of NTDs had different geographic distribution at the level of province. The urban–rural PRR of NTDs was 2.14 (95% CI: 1.94-2.34) in the north but only 1.47 (95% CI: 1.31-1.66) in the south.ConclusionsThere is a high total prevalence of NTDs, which remains one of the major public health concerns in China. Eliminating the geographic and urban–rural disparities in the disease burden is a priority for future intervention.