Nested case-control study on children with severe birth defects in Shanghai / 上海预防医学

ObjectiveTo design a prospective nested case-control study based on a city-wide birth cohort of Shanghai， so as to understand their health status and explore the influencing factors of birth defects. MethodsBased on the birth registration covering the entire city of Shanghai， the nested case-control study of children with severe birth defects was designed. Children born with severe birth defects were selected as the case group， and healthy children were matched as the control group. Basic information， health status， maternal pregnancy history， and survival outcome of children both in the case group and the control group were collected through medical history review and home visits. The logistic regression model was used for multivariate analysis. ResultsA total of 18 875 infants born between January 1， 2011， and December 31， 2021， were included， among which 11 500 （60.93%） were children with severe birth defects and 7 375 （39.07%） were healthy children. The logistic regression model analysis showed that being male （OR=1.20， 95%CI：1.13‒1.29）， non-Shanghai residency （OR=1.16， 95%CI： 1.06‒1.25）， multiple births （OR=8.41， 95%CI：6.25‒11.30）， artificial insemination （OR=2.31， 95%CI：1.34‒3.99）， in vitro fertilization （IVF） （OR=1.85， 95%CI：1.44‒2.38）， maternal exposure to radiation （OR=1.83， 95%CI：1.07‒3.14）， maternal illness during pregnancy （OR=1.61， 95%CI：1.49‒1.74）， experiencing a traumatic event during pregnancy （OR=2.34， 95%CI：1.88‒2.92）， paternal chemical exposure （OR=1.88， 95%CI：1.32‒2.69）， paternal radiation exposure （OR=1.65， 95%CI： 1.18‒2.33）， family history of birth defects （OR=8.18， 95%CI： 3.96‒16.89）， being overweight before pregnancy （OR=1.16， 95%CI： 1.07‒1.27）， being obese before pregnancy （OR=1.15， 95%CI：1.03‒1.30）， and being excessively obese before pregnancy （OR=1.52， 95%CI：1.26‒1.83） were risk factors for the occurrence of birth defects. Analysis by type of birth defect found that prematurity was a risk factor for cardiac malformations and cheilopalatoschisis （OR=27.87， 95%CI： 20.84‒37.27）， especially ranking first in cardiac malformations. ConclusionAfter controlling for influencing factors， maternal overweight， obesity， and excessive obesity before pregnancy， artificial insemination， and IVF are independent risk factors for the occurrence of birth defects. Choosing a healthy lifestyle， improving physical and mental health during pregnancy， and controlling BMI during pregnancy are beneficial in reducing the risk of birth defects.

Relationship between atmospheric pollutants and some adverse pregnancy outcomes / 中国比较医学杂志

The rapid development of the Chinese economy and the continuous advancement of urbanization have made the problem of air pollution more prominent,which may have an impact on people's health.In recent years,a large number of studies have emerged in the academic community both domestically and internationally.Many cohort studies have shown that during pregnancy,the surrounding air pollutants are relatively high,which may increase the risk of adverse pregnancy outcomes.So now people are paying more attention to the impact of air pollutants on the health of pregnant women or fetuses.This article provides a brief review of the impact of atmospheric pollutants on some adverse pregnancy outcomes and their possible biological mechanisms.

Proportion of Consanguineous Marriages in Community and Factors Affecting Pregnancy Outcome : A Hospital based Study in Ahmedabad City, Gujarat

Objectives : To find out (i) the proportion and the types of consanguinity and (ii) its correlation with fetal loss, neonatal deaths, complication related to obstetric and congenital abnormalities. Methods : All the delivered women at Tertiary Care Hospital were included in the cross sectional study during the study period. Total sample size was 6775. Information regarding educational status, occupation, consanguinity and pregnancy outcome was collected. Results : 17% consanguinity was found in selected people and among these marriages, 59.8% were between first cousins. There was highly significant difference observed between the consanguineous status of women and pregnancy outcome (Congenital malformations, abortion, Intrauterine death). Conclusion: The incidence of congenital abnormalities, Intrauterine Device (IUD) and abortion was found higher in Consanguineous marriages. There is a need to improve public awareness regarding problems related to Consanguineous marriages

Monitoring of birth defects in perinatal infants born during 2015-2019 in Huainan City, Anhui Province / 中国基层医药

Objective:To analyze birth defects in perinatal infants in Huainan city, Anhui province.Methods:The data of perinatal infants with birth defects born during 2015-2019 who were monitored in nine national and provincial birth defect monitoring hospitals in Huainan City were collected. The changes in birth defects, the incidence of birth defects in infants ≥ 28 weeks, urban and rural area distribution of birth defects, type of defects, and the related factors of birth defects during a 5-year study period were analyzed.Results:A total of 90 466 perinatal infants with the incidence of birth defects of 89.87/10 000 were monitored during 2015-2019. The incidence of birth defects in Anhui Province was 139.74/10 000. The proportion of preterm infants < 28 weeks with birth defects among full-term births with birth defects was 30.93% and the proportion increased year by year during 2015-2019, with the proportion of 14.84%, 31.69%, 34.83%, 32.84% and 34.02% respectively. The top five birth defects detected during 2015-2019 were multiple fingers (toes) ( n = 189, 20.89/10 000), cleft lip ( n = 96, 10.61/10 000), external ear deformity ( n = 79, 8.73/10 000), congenital heart disease ( n = 65, 7.19/10 000) and syndactyly ( n = 40, 4.42/10 000). The incidence of birth defects in males and females was 102.77/10 000 and 85.28/10 000, respectively. The incidence of birth defects in urban and rural areas were 107.38/10 000 and 79.60/10 000, respectively. Conclusion:The incidence of birth defects in preterm infants < 28 weeks in Huainan City was lower than that in the whole Anhui Province. The incidence of birth defects in Huainan City differed in different years. The incidence of birth defects in males was higher than that in females. From 2016, the incidence of birth defects in urban area was higher than that in rural area. Birth defects mainly consisted of multiple fingers (toes), external ear deformity, congenital heart disease, cleft lip and syndactyly. The detection rate of birth defects in preterm (< 28 weeks) patients was increased year by year. Early intervention effectively decreased the incidence of birth defects and improved the quality of the population in Huainan City.

Hereditary effects of ionizing radiation-a review of human epidemiological studies / 中华放射医学与防护杂志

Parental exposure to ionizing radiation (IR) can induce mutation in germline that may lead to genome instability, chromosomal aberrations, sex ratio variations, increased cancer susceptibility, and even increased probability of birth defects among their offspring, which substantially increase the burden of hereditary diseases. Up to now, the hereditary effect of IR has been observed in a number of species, but there is lack of evidence in humans. With reference to related studies in China and globally, this article reviews the human epidemiological studies of the hereditary effect of IR and briefly discusses why the hereditary effect of IR is not obvious in humans, so as to provide a reference for future assessment of the hereditary effect of radiation in China.

Surveillance of perinatal birth defects in Minhang District of Shanghai from 2014 to 2018 / 上海预防医学

Objective:To retrospectively characterize the perinatal birth defects in the latest 5 years in Minhang District of Shanghai， and provide the evidence to improve the preventive strategies. Methods:The data of perinatal birth defects was retrieved from “Shanghai information reporting system for children with birth defects and disabilities” ，which was recorded by five sentinel hospitals in Minhang District from January 2014 to December 2018. Average proportion of perinatal birth defects in the recent 5 years， annual variation， comparison with municipal data in the same period， difference between registered population and migrant population， difference between male and female， and common birth defects were determined. Results:The average proportion of perinatal birth defects in the recent 5 years was determined to be 6.24‰， which increased from 5.32‰ in 2014 to 7.90‰ in 2018. It was lower than the municipal proportion in Shanghai with an average of 11.02 ‰ （from 9.7 ‰ in 2014 to 14.00 ‰ in 2018）. The proportion was higher in resident population （9.15‰） than that in migrant population （5.57‰）. In addition， the proportion was higher in male infants （6.81‰） than that in female infants （5.59‰）. The first two common defects were congenital heart disease and polydactyly， while cleft lip and cleft lip with palate showed a decreasing trend. Conclusion:In the recent 5 years， the proportion of birth defect increases， which is consistent with the whole city. There remain challenges in the maternal and children healthcare.

The Effects of Folic Acid in Fetuses and Newborns / 中国药学杂志

Folic acid is one of the essential nutrients for human health. Folic acid supplementation during pregnancy is important to prevent fetal neural tube defects. This article briefly reviews its current clinical use from the basic characteristics and mechanism of folic acid, and also reviews the latest literature of fetal, neonatal and children. The terms such as "fetus", "newborn", "folate", "infant, newborn" [Mesh], and "folic acid" [Mesh] are used to search for relevant research from China National Knowledge Infrastructure, Wanfang, PubMed and The Cochrane Library. Summary of domestic and foreign studies: folic acid may be associated with fetal neural tube defects, the relationship between folic acid and fetal birth defects, fetal growth restriction and perinatal mortality remains to be further studied; in addition, folic acid is associated with neonatal asphyxia and brain injury; may be associated with childhood asthma, mental retardation and immunity. It can be seen that although the correlation between folic acid and various diseases still needs more scientific research, it is recommended that periconception and pregnant should reasonably supplement folic acid.

Folic acid and birth defects / 国际儿科学杂志

Folic acid deficiency is associated with birth defects such as fetal spina bifida and congenital heart disease.Folic acid supplementation during pregnancy can prevent various birth defects, but excessive folic acid may increase the risk of certain diseases.This article reviews the causes of folate deficiency, single nucleotide polymorphisms of folate metabolism-related enzyme genes, the mechanism of birth defects caused by folic acid deficiency, and the correct supplementation of folic acid to prevent birth defects.

Clinical and socioeconomic factors associated with delayed orchidopexy in cryptorchid boys in China: A retrospective study of 2423 cases / 亚洲男科学杂志(英文版)

We investigated the associations of clinical and socioeconomic factors with delayed orchidopexy for cryptorchidism in China. A retrospective study was conducted on cryptorchid boys who underwent orchidopexy at Children's Hospital at Chongqing Medical University in China from January 2012 to December 2017. Of 2423 patients, 410 (16.9%) received timely repair by 18 months of age, beyond which surgery was considered delayed. Univariate analysis suggested that the laterality of cryptorchidism (P = 0.001), comorbidities including inguinal hernia/scrotal hydrocele (P < 0.001) or urinary tract disease (P = 0.016), and whether patients lived in a poverty county (P < 0.001) could influence whether orchidopexy was timely or delayed. Logistic regression analysis suggested that the following factors were associated with delayed repair: unilateral rather than bilateral cryptorchidism (odds ratio [OR] = 1.752, P < 0.001), absence of inguinal hernia or hydrocele (OR = 2.027, P = 0.019), absence of urinary tract disease (OR = 3.712, P < 0.001), and living in a poverty county (OR = 2.005, P < 0.001). The duration of postoperative hospital stay and hospital costs increased with the patient's age at the time of surgery.

Mathematical model for predicting birth defect trend in Xi'an / 西安交通大学学报(医学版)

Objective: To understand the trend of birth defects in Xi'an by using gray model, ARIMA and NAR. Methods: The birth defects monitoring data of perinatal infants from 28-week pregnant women to 7 days after birth were collected from all the hospitals with obstetrical department in Xi'an during 2003 and 2015. The incidence of birth defects data from October 2003 to September 2015 in Xi'an City were used to construct the data model. We compared data with the actual birth defects rate from October 2003 to September 2015 to further optimize and make supplement for the model, and then predicted the incidence of birth defects in Xi'an from 2016 to 2017. Microsoft Excel 2003 was used for data input and SPSS version 16.0 was used for statistical analysis. Matlab was used for Gray Model and NAR prediction. ARIMA mathematical model was predicted by R software. Results: The grey prediction model suggested that the birth defects rate in the four quarters of 2016 and 2017 was 9.62‰, 9.67‰, 9.72‰, 9.77‰, 9.82‰, 9.87‰, 9.92‰ and 9.97‰, which was in slow increase. The ARIMA model predicted that the birth defects rate in Xi'an would still fluctuate at a high level in 2016 and 2017, and the rate in the four quarters was 11.98‰, 12.83‰, 11.28‰, 11.78‰, 12.23‰, 11.73‰, 11.80‰ and 12.00‰. The NAR model predicted that the birth defects rate in Xi'an was 13.24‰, 17.91‰, 10.55‰, 16.08‰, 16.47‰, 9.42‰, 11.99‰ and 11.68‰. The birth defects rate would reach the peak in 2016 and decrease in 2017. Comparison of the above three models showed that the root mean square error of grey prediction model, ARIMA model and NAR model was 1.353 009, 1.181 373 and 0.555 347, respectively. Conclusion: Based on the prediction by the above three mathematical models, it shows that NAR model is more accurate and reliable in predicting the data of this study, followed by ARIMA and grey model. Effective intervention measures for birth defects are still the key task of public health for a long time.

Application of the gray model GM (1, 1) in predicting birth defects / 西安交通大学学报(医学版)

Objective: To investigate the application of gray model GM(1, 1) in predicting the incidence of birth defects at different levels and the effect of data volatility on the prediction outcome. Methods: Based on the monitoring data of birth defects in Xi'an from October 2009 to September 2016, the GM(1, 1) was used to predict the overall incidence of birth defects and incidence of five main birth defects at three levels (month, quarter, and year). We compared the fitting accuracy of different level prediction models. Results: The average relative error for yearly prediction of overall birth defect was 4.6%, and the mean square deviation was 0.259, which might suggest better prediction. Quarterly forecasting results were almost qualified and the average relative error was 10.2%. Monthly prediction was poor with an average relative error of 17.5%. With the extension of the forecast period, the grey model prediction results of the top five birth defects (congenital heart disease, cleft lip and palate, neural tube defects, multiple fingers, and congenital hydrocephalus) in Xi'an all increased, and the fitting accuracy gradually improved. The gray scale of the year was the best. Conclusion: The prediction results of the gray model may be related to the volatility of the data. It may be suitable for predicting the incidence of birth defects by the year.

Folic acid and birth defects / 国际儿科学杂志

Folic acid deficiency is associated with birth defects such as fetal spina bifida and congenital heart disease. Folic acid supplementation during pregnancy can prevent various birth defects, but excessive fo-lic acid may increase the risk of certain diseases. This article reviews the causes of folate deficiency, single nu-cleotide polymorphisms of folate metabolism-related enzyme genes, the mechanism of birth defects caused by folic acid deficiency, and the correct supplementation of folic acid to prevent birth defects.

Application of chromosome microarray analysis in neonatal birth defects / 中华实用儿科临床杂志

Objective@#To explore the application of chromosomal microarray analysis (CMA) in neonatal birth defects and further determine the frequency of chromosome imbalances in neonates with birth defects.@*Methods@#Retrospective analysis was performed in 121 neonates with specific features, such as distinctive facial features, congenital heart disease, congenital malformation, neonatal decreased responsive, hypotonia, seizures and others at the Department of Neonatology, Guangdong Women and Children Hospital from May 2016 to November 2017.All the cases were analyzed by using chromosomal microarray analysis (CMA).@*Results@#A total of 23 (19.0%) patients were identified with pathogenic CNVs, 3 patients (2.5%) with uncertain clinical significant CNVs.There were 5 patients (4.1%)with chromosome numerical abnormalities, 12 patients (9.9%)with microdeletion/microduplication syndrome, 6 patients (5.0%) with chromosome deletion or duplication.All groups whose incidence was sorted from high to low were facial characters(30.3%), congenital malformation(21.6%), neonatal decreased responsive(9.1%) and other indications(6.7%).@*Conclusions@#CMA is a valuable clinical diagnostic tool that allows precise identification of chromosome imbalances as the cause of birth defects in neonates.CMA can detect many more clinically relevant genomic abnormalities than conventional cytogenetic study and assist the clinician in diagnosis, early neonatal intervention, and genetic counseling.

Clinical and socioeconomic factors associated with delayed orchidopexy in cryptorchid boys in China: a retrospective study of 2423 cases / 亚洲男科学杂志(英文版)

We investigated the associations of clinical and socioeconomic factors with delayed orchidopexy for cryptorchidism in China. A retrospective study was conducted on cryptorchid boys who underwent orchidopexy at Children's Hospital at Chongqing Medical University in China from January 2012 to December 2017. Of 2423 patients, 410 (16.9%) received timely repair by 18 months of age, beyond which surgery was considered delayed. Univariate analysis suggested that the laterality of cryptorchidism (P = 0.001), comorbidities including inguinal hernia/scrotal hydrocele (P < 0.001) or urinary tract disease (P = 0.016), and whether patients lived in a poverty county (P < 0.001) could influence whether orchidopexy was timely or delayed. Logistic regression analysis suggested that the following factors were associated with delayed repair: unilateral rather than bilateral cryptorchidism (odds ratio [OR] = 1.752, P < 0.001), absence of inguinal hernia or hydrocele (OR = 2.027, P = 0.019), absence of urinary tract disease (OR = 3.712, P < 0.001), and living in a poverty county (OR = 2.005, P < 0.001). The duration of postoperative hospital stay and hospital costs increased with the patient's age at the time of surgery.

Analysis of birth defect rate trend of cleft lip and palate in Shanghai from 2007 to 2016 / 中华口腔医学杂志

Objective@#To analysis the rate of birth defects of cleft lip and palate among newborns in Shanghai during 2007 and 2016 and describe its change trend, for the purpose of prevention, treatment and nursing of newborns with cleft lip and palate.@*Methods@#Birth registration information in Shanghai during January 2007 and December 2016 were collected. Rate of birth defects, gender ratio and maternal age of newborns with cleft lip and palate were analyzed. Annual percent change was applied to analyze the trend.@*Results@#The total birth defect rate of children with cleft lip and palate was 937/million in the past 10 years in Shanghai, showing an overall decreasing trend, decreased 28.20% compared to the data of 2007. The total birth defect rate of newborns with cleft lip decreased 40.86%. Overall decline rate of newborns with cleft lip and palate was 54.60%, but birth defect rate of newborns with the isolated cleft palate rised 14.34%. The number of female isolated cleft palate newborns were 1.6 times higher than those of male isolated cleft palate newborns, male newborns with cleft lip were 1.8 times higher than that of the female newborns with cleft lip. Male newborns with cleft lip and palate were 1.5 times as much as the female newborns with cleft lip and palate. Maternal age is mainly 25 to 29 years old, accounting for 42.01% of the total number of mothers, the according birth defect rate was lowest as 853/million. When maternal age is too low or too high, the risk of neonatal cleft lip and palate could increase. Birth defects of cleft lip and palate was up to 130.8/million when maternal age is less than 20, while birth defects of cleft lip and palate was up to 188.2/million when maternal age over 40 years old.@*Conclusions@#In recent 10 years, the overall rate of birth defects of cleft lip and palate in Shanghai shows a decreasing trend, with cleft lip and palate declining obviously, but isolate cleft palate has an increasing tendency. Maternal age less than 20 years old or more than 40 years old will increase the risk of birth defects in newborns with cleft lip and palate.

The occurrence of macrosomia and its influencing factors / 西安交通大学学报(医学版)

Objective To analyze the factors influencing the occurrence of macrosomia so as to provide a theoretical basis for the prevention of macrosomia.Methods The data were selected from the findings of Survey on Prevalence and Risk Factors for Birth Defects in Shaanxi Province.This study intended to select data of macrosomia in Xianyang City and its influencing factors for statistical analysis.The rates were compared by χ2 ;the influencing factors were analyzed by univariate and multivariate Logistic regression.Results The incidence of fetal macrosomia among single live birth neonates in Xianyang was 5.2%.The incidence of macrosomia was 6.5%in males and 4.2% in females,with a significant difference (P <0.001).From 2010 to 2013 the annual incidence rate of macrosomia was 5.4%,6.2%,5.9% and 4.4%,with no significant difference (P =0.151).The incidence rate of macrosomia in urban and rural areas was 6.3% and 5.5%,respectively,without significant difference (P =0.556).The incidence of macrosomia was 3.2% in Binxian County,5.6% in Changwu County,6.7% in Liquan County,5.4% in Qianxian County,8.0% in Wugong County,and 4.2% in Xunyi County,with significant differences (P <0.001).Logistic regression analysis showed that the occurrence of macrosomia was related to the baby's sex,mother's age,the times of pregancy,the time of antenatal care,alcohol intake during pregnancy and father's occupation.Conclusion The incidence of macrosomia of Xianyang from 2010 to 2013 was close to the national average.The sex of baby,mother's age,the times of pregnancy,the times of antenatal care,drinking history during pregnancy and father's occupation may affect the occurrence of macrosomia.

The occurrence of macrosomia and its influencing factors / 西安交通大学学报(医学版)

Objective To analyze the factors influencing the occurrence of macrosomia so as to provide a theoretical basis for the prevention of macrosomia.Methods The data were selected from the findings of Survey on Prevalence and Risk Factors for Birth Defects in Shaanxi Province.This study intended to select data of macrosomia in Xianyang City and its influencing factors for statistical analysis.The rates were compared by χ2 ;the influencing factors were analyzed by univariate and multivariate Logistic regression.Results The incidence of fetal macrosomia among single live birth neonates in Xianyang was 5.2%.The incidence of macrosomia was 6.5%in males and 4.2% in females,with a significant difference (P <0.001).From 2010 to 2013 the annual incidence rate of macrosomia was 5.4%,6.2%,5.9% and 4.4%,with no significant difference (P =0.151).The incidence rate of macrosomia in urban and rural areas was 6.3% and 5.5%,respectively,without significant difference (P =0.556).The incidence of macrosomia was 3.2% in Binxian County,5.6% in Changwu County,6.7% in Liquan County,5.4% in Qianxian County,8.0% in Wugong County,and 4.2% in Xunyi County,with significant differences (P <0.001).Logistic regression analysis showed that the occurrence of macrosomia was related to the baby's sex,mother's age,the times of pregancy,the time of antenatal care,alcohol intake during pregnancy and father's occupation.Conclusion The incidence of macrosomia of Xianyang from 2010 to 2013 was close to the national average.The sex of baby,mother's age,the times of pregnancy,the times of antenatal care,drinking history during pregnancy and father's occupation may affect the occurrence of macrosomia.

Application of multiple seasonal ARIMA model in predication of birth defect incidence in Xi'an area / 西安交通大学学报(医学版)

Objective To predict the incidence of birth defects in Xi'an using the auto-regressive integrated moving average product seasonal model.Methods In Xi'an,the trend of the incidence of birth defects was analyzed and tested from October 2009 to August 2015.Using the data from September to December 2015,the actual birth defects were compared with the model fitting data to evaluate the predictive performance of the model.Multiple seasonal ARIMA model was then fitted under time series to predict the incidence of birth defects in 2016.Results Seasonal effect was seen in the incidence of birth defects in Xi'an.A multiple seasonal ARIMA(0,0,1) (0,1,1)12 was established.The mean of absolute error and the relative error were 9.5 and 0.084,respectively,when compared to the simulated number of patients from September to December in 2015,suggesting that ARIMA (0,0,1) (0,1,1)12 has a better predictive ability.Results under the prediction of multiple seasonal ARIMA model showed that the number of patients in 2016 was similar to that of 2015 in Xi'an,with a slight increase and a decrease in the peak value.Conclusion Multiple seasonal ARIMA(0,0,1)(0,1,1)12 model could be used to successfully predict the incidence of birth defects in Xi'an.

The epidemiological characteristics of perinatal birth defects in Xi'an from 2010 to 2015 / 西安交通大学学报(医学版)

Objective To investigate the dynamic epidemiological characteristics of perinatal birth defects in Xi'an so as to provide scientific evidence for the priority of future birth defect prevention.Methods We made a statistical description of the data of perinatal birth defects from 2010 to 2015 reported by all the maternity hospitals in Xi'an.Results The incidence of birth defects in Xi'an from 2010 to 2015 was 89.62/104 (87.60/104,91.74/ 104) and had an annual ascending tendency (x2-157.13,P＜0.01).The top five main birth defects in a descending order were congenital heart disease (26.53/104),polydactyly (13.10/104),total cleft lip (11.42/104),neural tube defects (6.06 /104),and congenital hydrocephalus (5.08/104),accounting for 69.39％ of the total number of birth defects.And the incidence of congenital heart diseases showed a year-by-year ascending trend (x2=837.65,P＜ 0.01).The incidence of birth defects was higher in urban areas than in rural areas (OR 1.108,95％ CI:1.056-1.162).The birth defects were more frequently seen in males than in females (OB=1.151,95％ CI:1.097-1.208).Mother's age ＜20 (OR=1.764,95％ CI..1.532-2.032) and mother'sage≥35 (OR=1.283,95％ CI:1.179-1.395) also were risk factors for birth defects.Up to 72.54％ of the defects were live births.There were 52.83％ cases diagnosed by ultrasound and 46.24％ ones by clinical examination.The prenatal diagnosis rate was 33.20％.Conclusion The incidence of perinatal birth defects in Xi'an from 2010 to 2015 showed an annual ascending trend.We should improve the prenatal diagnosis level of all monitored hospitals in order to reduce incidence of birth defects and increase the quality of population.

Time-series analysis of air pollution and birth defects during 2010 to 2015 in Xi'an / 西安交通大学学报(医学版)

Objective To study the effects of air pollution including sulphur dioxide (SO2),nitrogen dioxide (NO2) and PM10 in Xi'an on birth defects.Methods We collected the birth defects data from Xi'an Maternal and Child Health Hospital,meteorological data from Xi'an Bureau of Meteorology,and the air pollution data from Xi'an Environment Monitoring Station from 2010 to 2015.Generalized additive model (GAM) was used to explore the relationship between air pollution and birth defects after adjusting the effects of long-term and seasonal trend,temperature,and relative humidity.Results The monthly average birth defects were 89 cases;the monthly average concentration of SO2,NO2 and PM10 was 34.05 μg/m3,45.13 μg/m3,and 96.77 μg/m3,respectively.In the GAM,the monthly average temperature was 13.57 ℃ and the relative humidity was 63.20％.The three kinds of air pollutants all had a certain lag effect in 10 months,which reached the maximum.With an increase of concentration by 10 μg/m3 in three air pollutants,the relative risks and confidence interval of SO2,NO2,and PM10 were 1.060 (1.023-1.097),1.033 (1.014-1.052) and 1.018 (1.007-1.029),with significant differences (P＜0.05).Conclusion Exposure to SO2,NO2,and PM10 may be associated with the risk of birth defects.