Trends in the prevalence of congenital hydrocephalus in 14 cities in Liaoning province, China from 2006 to 2015 in a population-based birth defect registry from the Liaoning Women and Children's Health Hospital

Independent factors associated with birth defects during the whole of pregnancy in Shenyang City, China: a case-control study

Background

Birth defects, as a kind of diseases that seriously affect human life, have always attracted much attention. In the past, perinatal data have been studied for birth defects. This study analyzed the surveillance data of birth defects during the perinatal period and the whole of pregnancy, as well as the independent influencing factors, to help to minimize their risk of birth defects.

Methods

A total of 23,649 fetuses delivered in the hospital from January 2017 to December 2020, were enrolled in this study. There were 485 cases of birth defects, including live births and stillbirths by detailed inclusion and exclusion criteria. Maternal and neonatal clinical data were collated to analyze the influencing factors associated with birth defects. Pregnancy complications and comorbidities were diagnosed according to the criteria of the Chinese Medical Association. Univariate and multivariate logistic regression models were used to investigate the association between independent variables and birth defect events.

Results

The incidence of birth defects during the whole of pregnancy was 175.46/10,000, while the incidence of perinatal birth defects was 96.22/10,000. The birth defect group had significantly higher maternal age, gravidity, parity, rate of preterm birth, cesarean section (CS) rate, scarred uterus, stillborn, and male newborns compared to the control group. Multivariate logistic regression model analysis showed that preterm birth [odds ratio (OR): 1.69, 95% confidence interval (CI): 1.01 to 2.86], CS (OR: 1.46, 95% CI: 1.08 to 1.98), scarred uterus (OR: 1.70, 95% CI: 1.01 to 2.85), and low birth weight (OR >4 compared to the other two classes) were significantly associated with birth defects during the whole of pregnancy (all P<0.05). The independent influencing factors associated with perinatal birth defects included CS (OR: 1.43, 95% CI: 1.05 to 1.93), gestational hypertension (OR: 1.70, 95%: 1.04 to 2.78), and low birth weight (OR >3.70 compared to the other two classes).

Conclusions

The discovery and monitoring of known influencing factors associated with birth defects, such as, preterm birth, gestational hypertension, low birth weight, should be enhanced. For the controllable influencing factors, obstetrics providers should work with patients to minimize their risk of birth defects.

Association Between Maternal Exposure to SO2 and Congenital Ear Malformations in Offspring: A Population-Based Case-Control Study in Liaoning Province, China

Objectives: To examine associations between maternal sulfur dioxide (SO2) exposure and congenital ear malformations risk in offspring.

Methods: We surveyed 1676 cases with congenital ear malformations and 7950 controls from the Maternal and Child Health Certificate Registry of Liaoning Province between 2010 and 2015. SO2 concentrations were obtained from the Municipal Environment Protection Bureau of Liaoning Province. Multivariable logistic regression models and Restricted cubic splines (RCS) model were used to assess the aforementioned association.

Results: There were significant associations between maternal SO2 exposure and congenital ear malformations risk during the 3 months before conception (OR Q4 vs. Q1 = 1.93, 95% CI = 1.43–2.59) and the 3 months after conception (OR Q4 vs. Q1 = 1.63, 95% CI = 1.22–2.18). Similar results were obtained in the analysis of single-month exposure windows, except for the third month before conception and the third month after conception. Moreover, these findings were broadly consistent across subgroups and robust in sensitivity analyses. There were non-linear dose-response associations between SO2 exposure and congenital ear malformations based on restricted cubic spline model analysis.

Conclusion: Maternal SO2 exposure is associated with increased congenital ear malformations risk in offspring.

Analysis of early neonatal case fatality rate among newborns with congenital hydrocephalus, a 2000-2014 multi-country registry-based study

BACKGROUND

Congenital hydrocephalus (CH) comprises a heterogeneous group of birth anomalies with a wide-ranging prevalence across geographic regions and registry type. The aim of the present study was to analyze the early neonatal case fatality rate (CFR) and total birth prevalence of newborns diagnosed with CH.

METHODS

Data were provided by 25 registries from four continents participating in the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR) on births ascertained between 2000 and 2014. Two CH rates were calculated using a Poisson distribution: early neonatal CFR (death within 7 days) per 100 liveborn CH cases (CFR) and total birth prevalence rate (BPR) per 10,000 births (including live births and stillbirths) (BPR). Heterogeneity between registries was calculated using a meta-analysis approach with random effects. Temporal trends in CFR and BPR within registries were evaluated through Poisson regression modeling.

RESULTS

A total of 13,112 CH cases among 19,293,280 total births were analyzed. The early neonatal CFR was 5.9 per 100 liveborn cases, 95% confidence interval (CI): 5.4-6.8. The CFR among syndromic cases was 2.7 times (95% CI: 2.2-3.3) higher than among non-syndromic cases (10.4% [95% CI: 9.3-11.7] and 4.4% [95% CI: 3.7-5.2], respectively). The total BPR was 6.8 per 10,000 births (95% CI: 6.7-6.9). Stratified by elective termination of pregnancy for fetal anomalies (ETOPFA), region and system, higher CFR were observed alongside higher BPR rates. The early neonatal CFR and total BPR did not show temporal variation, with the exception of a CFR decrease in one registry.

CONCLUSIONS

Findings of early neonatal CFR and total BPR were highly heterogeneous among registries participating in ICBDSR. Most registries with higher CFR also had higher BPR. Differences were attributable to type of registry (hospital-based vs. population-based), ETOPFA (allowed yes or no) and geographical regions. These findings contribute to the understanding of regional differences of CH occurrence and early neonatal deaths.

Maternal Exposure to Sulfur Dioxide and Risk of Omphalocele in Liaoning Province, China: A Population-Based Case-Control Study

Evidence of the association between maternal sulfur dioxide (SO₂) exposure and the risk of omphalocele is limited and equivocal. We aimed to assess the aforementioned topic during the first trimester of pregnancy. A population-based case-control study was carried out in infants consisting of 292 cases of omphalocele and 7,950 healthy infant controls. Exposure to SO₂, particulate matter with aerodynamic diameters ≤ 10 μm, and nitrogen dioxide was assessed by averaging the concentration from all stations in the mother's residential city. SO₂ exposure was categorized into three groups, with the lowest tertile defined as the reference category. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using multivariable logistic regression models. Higher SO₂ exposure during the first trimester was significantly associated with omphalocele risk [per standard deviation (42 ug/m³) increment: OR = 1.39, 95% CI = 1.22–1.65]. When focusing on shorter exposure windows, similar positive associations were observed for SO₂ exposure in the first and third months of pregnancy. In addition, compared with the lowest tertile, high SO₂ exposure in the second month of pregnancy increased the risk of omphalocele (OR = 2.80, 95% CI = 1.61–4.97). Maternal exposure to SO₂ during the first trimester may increase the risk of omphalocele in offspring.

Congenital Hydrocephalus and Associated Risk Factors: An Institution-Based Case–Control Study, Dessie Town, North East Ethiopia

Introduction

Congenital hydrocephalus is one of the commonest congenital anomalies of the central nervous system. It is characterized by extensive accumulation of cerebrospinal fluid within the ventricles of the brain due to an imbalance between synthesis and absorption of cerebrospinal fluid. This study was planned to investigate the incidence and associated risk factors of congenital hydrocephalus.

Methods

Unmatched case–control study was conducted in 34 (cases) and 104 (controls) pregnant women. Maternal data were collected from a structured questionnaire, and fetal-related data were recorded from obstetric ultrasound. Epi-info 7 and SPSS version 24 were used for data entry and analysis, respectively. The association between congenital hydrocephalus and risk factors was evaluated using binary logistic regression.

Results

The incidence of congenital hydrocephalus was 2.67 per 1000 pregnancies. The result of multivariate logistic regression indicated that alcohol use and iron with folic acid supplementation during pregnancy were significantly associated with the development of congenital hydrocephalus (OR: 7.64, 95% CI: 1.97–29.66 and p-value: 0.003 and OR: 0.186, 95% CI: 0.07–0.49 and p-value: 0.001, respectively). Maternal exposure to typhus and typhoid and use of antibiotics during early pregnancy were also significantly associated with congenital hydrocephalus. Moreover, significant association was also observed between the simultaneous development of spina bifida and congenital hydrocephalus (p-value 0.03).

Conclusion

In conclusion, alcohol consumption, unprescribed use of antibiotics and infection during pregnancy as well as absence of folic acid supplementation may predispose to congenital hydrocephalus.

Association between maternal exposure to PM10 and risk of anorectal atresia/stenosis in offspring: a population-based case-control study in Liaoning Province, China

The potential association between maternal exposure to PM₁₀ ranging from 3 months prior to conception to the end of the early trimester and the risk of anorectal atresia/stenosis in offspring has not been established. Thus, we determined the association between maternal exposure to PM₁₀ and risk of anorectal atresia/stenosis in offspring in this study. We recruited 713 patients including 480 male and 233 female with anorectal atresia/stenosis and 7950 randomly selected healthy offspring from the Maternal and Child Health Certificate Registry of Liaoning Province and delivered between 1 January 2010 and 31 December 2015. Monthly PM₁₀ concentrations were retrieved from the Environment Protection Bureau of each city in Liaoning Province. We established a multivariable logistic regression model to calculate the adjusted odds ratios (ORs) and 95% confidence intervals (CIs). Maternal exposure to PM₁₀ was associated with an increased risk for anorectal atresia/stenosis in offspring during the 3 months prior to conception (per 10 μg/m³ increment: OR = 1.15, 95% CI = 1.03-1.20; per SD [27 μg/m³] increment: OR = 1.33, 95% CI = 1.09-1.63) and the first trimester (per 10 μg/m³ increment: OR = 1.08, 95% CI = 1.00-1.17; per SD [28 μg/m³] increment: OR = 1.26, 95% CI = 1.01-1.57). Evaluation of the association with a shorter exposure window (1 month) revealed a positive association between anorectal atresia/stenosis and PM₁₀ from the 3rd month prior to pregnancy to each month of the 1st trimester. Maternal exposure to PM₁₀ 3 months prior to conception and during the 1st trimester was associated with an increased risk of anorectal atresia/stenosis in the offspring. Future perspective cohort studies are needed to confirm our findings.

Interpregnancy interval and subsequent perinatal risk of congenital heart disease in Guangzhou, Southern China: a retrospective cohort study, 2014-2019

BACKGROUND

The association between maternal interpregnancy interval (IPI) and congenital heart disease (CHD) in neonates remains inconclusive. This study aimed to examine the effect of maternal IPI on birth risk of CHD.

METHODS

Chinese women with two consecutive singleton deliveries in Guangzhou between January 2014 and December 2019 were selected as participants. Information on IPI and CHD was extracted from the Guangzhou Perinatal Health Care and Delivery Registry and the Guangzhou Birth Defects Surveillance Program. We stratified IPI into four categories: <24 months, 24-35 months, 36-59 months, and ≥60 months. A multivariate logistic regression model was used to examine the association between IPI and CHD. Subgroup analysis was also performed to assess whether the associations differed across top three CHD subtypes.

RESULTS

For 119,510 women enrolled in this study, the mean ages at two consecutive deliveries were 26.2 ± 3.8 and 28.8 ± 4.0 years, which yielded a median IPI of 51.2 (interquartile range, 32.1-77.2) months. Among them, 828 delivered infants with CHD during their second pregnancy. There was a J-shaped curve relationship between IPI and CHD with the lowest birth prevalence (5.33‰) at 24-35-month interval. Compared to women with an IPI of 24-35 months, those with an IPI ≥60 had an increased risk of delivering infants with CHD (adjusted odds ratio (OR), 1.41; 95% confidence interval (CI), 1.19-1.64). However, for those with an IPI <24 months (adjusted OR, 1.24; 95% CI, 0.97-1.51), IPI was statistically insignificant associated with the risk of delivering infants with CHD (p = .12). There were different patterns of associations for different CHD subtypes.

CONCLUSIONS

Longer maternal IPI (≥60 months) was associated with an increased risk of delivering infants with CHD in the Chinese population.

Maternal PM10 Exposure Increases Risk for Spina Bifida: A Population-Based Case-Control Study

Limited studies have focused on the impact of ambient air pollution on spina bifida. A population-based case-control study was conducted in Liaoning Province, China to assess the associations between maternal PM₁₀ exposures in various exposure windows and spina bifida risk. Data on spina bifida cases born between 2010 and 2015 were available from the Maternal and Child Health Certificate Registry of Liaoning Province. Controls were a random sample of healthy livebirths without any birth defects delivered in the selected five cities during 2010–2015. Ambient air monitoring data for PM₁₀ were obtained from 75 monitoring stations in Liaoning Province. The multivariable logistic regression models were established to calculate adjusted odds ratios (OR) and 95% confidence intervals (CI). We further performed sensitivity analyses by using three propensity score methods. A total of 749 spina bifida cases and 7,950 controls were included. After adjusting for potential confounders, spina bifida was associated with a 10 μg/m³ increment in PM₁₀ during the first trimester of pregnancy (adjusted OR = 1.06, 95% CI: 1.00–1.12) and the 3 months before pregnancy (adjusted OR = 1.12, 95% CI: 1.06–1.19). The adjusted ORs in the final model for the highest vs. the lowest quartile were 1.51 (95% CI: 1.04–2.19) for PM₁₀ during the first trimester of pregnancy and 2.01 (95% CI: 1.43–2.81) for PM₁₀ during the 3 months before pregnancy. Positive associations were found between PM₁₀ exposures during the single month exposure windows and spina bifida. Sensitivity analyses based on two propensity score methods largely reported similar positive associations. Our findings support the evidence that maternal PM₁₀ exposure increases the risk of spina bifida in offspring. Further, validation with a prospective design and a more accurate exposure assessment is warranted.

Maternal exposure to sulfur dioxide before and after conception and the risk of hypospadias in offspring

As far as we know, there have been no studies exploring the association between maternal sulfur dioxide (SO₂ ) exposure and the risk of hypospadias in offspring. We aimed to evaluate this association during the 3 months before conception and the first trimester. A population-based case-control study was conducted in male infants, consisting of 348 cases of hypospadias and 4023 controls. Maternal exposure to SO₂ , particulate matter with aerodynamic diameters ≤10 μm (PM₁₀ ), and nitrogen dioxide (NO₂ ) was assessed by averaging the concentrations recorded at all stations in the mother's city of residence. Air pollutants were tested for multicollinearity using variance inflation factor analysis. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by multivariable logistic regression models. SO₂ exposure during the 3 months before conception was significantly associated with the risk of hypospadias (highest tertile: OR = 7.40, 95% CI: 3.54-15.62). When focusing on shorter exposure windows, similar associations were observed for SO₂ exposure in the first and second month before and the first month after conception. In conclusion, maternal exposure to SO₂ during the 3 months before and the first and second months after conception may increase the risk of hypospadias in offspring.

Maternal exposure to ambient SO2 and risk of polydactyly and syndactyly: a population-based case-control study in Liaoning Province, China

Evidence links exposure to maternal sulfur dioxide (SO₂) and the risk of limb defects have been inconsistent. To investigate associations between SO₂ exposure during preconception and the first trimester and risks of polydactyly and syndactyly. The study population was acquired from the Maternal and Child Health Certificate Registry of Liaoning Province between 2010 to 2015, and consisted of 2605 polydactyly, 595 syndactyly cases, and 7950 controls. Ambient air pollutants levels were retrieved from air quality monitoring stations. We used multivariable logistic regression model to assess the adjusted odds ratios (ORs) and 95% confidence intervals (CIs). We found that exposure to increased SO₂ concentrations was associated with polydactyly during both the 3 months preconception (OR_{Q4 vs. Q1} = 3.76; 95% CI 2.61, 5.42; per 10 μg/m³ increment: OR = 1.07; 95% CI 1.04, 1.10) and the first trimester (OR_{Q4 vs. Q1} = 2.03; 95% CI 1.41, 2.92; per 10 μg/m³ increment: OR = 1.07; 95% CI 1.03, 1.11). However, we only observed increased risk for syndactyly in the analysis of high vs. low quartiles (three months preconception: OR_{Q4 vs. Q1} = 3.72; 95% CI 2.05, 6.75; first trimester: OR_{Q4 vs. Q1} = 1.98; 95% CI 1.11, 3.51). Most results of analyses based on single-month exposure window generally showed similar positive associations. Additionally, these findings were broadly consistent across subgroups and sensitivity analyses. Maternal SO₂ exposure increase the risk of polydactyly and syndactyly.

Maternal exposure to ambient particulate matter 10 μm or less in diameter before and after pregnancy, and anencephaly risk: A population-based case-control study in China

BACKGROUND

There is no epidemiological evidence on the effects of maternal exposure to ambient particulate matter 10 μm or less in diameter (PM₁₀) and anencephaly risk in offspring.

METHODS

We conducted a population-based case-control study in Liaoning Province, China. The case group consisted of 663 cases with anencephaly and the control group consisted of 7950 healthy infants from the Maternal and Child Health Certificate Registry of Liaoning Province that were born between 2010 and 2015. Daily PM₁₀ concentrations were obtained from 77 monitoring stations located within the study area. A multivariable logistic regression model was established to calculate the adjusted odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Maternal PM₁₀ exposure was significantly associated with an increased risk of anencephaly at three months before conception (highest versus lowest tertile: OR = 1.74, 95% CI: 1.29-2.34; per 10 μg/m³ increment: OR = 1.13, 95% CI: 1.06-1.20) and three months after conception (highest versus lowest tertile: OR = 1.93, 95% CI: 1.44-2.60; per 10 μg/m³ increment: OR = 1.01, 95% CI: 0.95-1.08). The evaluation of shorter exposure windows revealed similar associations for PM₁₀ exposure from the third month before pregnancy to the third month after pregnancy.

CONCLUSIONS

Maternal PM₁₀ exposure is positively associated with anencephaly risk during the critical period of neural system development.

Association between maternal exposure to PM10 and polydactyly and syndactyly: A population-based case-control study in Liaoning province, China

BACKGROUND

The number of studies on air pollution with birth defects as the primary outcome has increased dramatically over the past two decades, but the potential role of specific air pollutants in congenital limb anomalies remains unclear.

OBJECTIVES

To evaluate associations between preconception and first-trimester PM₁₀ exposure and polydactyly and syndactyly in a population-based case-control study.

METHODS

Polydactyly cases (n = 2605), syndactyly cases (n = 595), and controls without any birth defects (n = 7950) born between 2010 and 2015 were selected from the Maternal and Child Health Certificate Registry of Liaoning Province. The monthly mean PM₁₀ concentrations were obtained from 75 air monitoring stations, and the exposure assessment was based on the mean concentration of all stations in mother's residential city. A multivariable logistic regression model was constructed to calculate adjusted odds ratios (aORs) and 95% confidence intervals (CIs).

RESULTS

PM₁₀ exposure was positively associated with the risks of polydactyly (preconception: aOR_{T3 vs. T1} = 1.95, 95% CI 1.56-2.45, aOR = 1.06, 95% CI 1.01-1.10 [per 10-μg/m³ increment]; first-trimester: aOR_{T3 vs. T1} = 2.51, 95% CI 2.00-3.15) and syndactyly (preconception: aOR_{T3 vs. T1} = 2.86, 95% CI 1.98-4.13, aOR = 1.11, 95% CI 1.03-1.20 [per 10-μg/m³ increment]; first-trimester: aOR_{T3 vs. T1} = 3.10, 95% CI 2.11-4.56). Analyses based on single month exposure windows basically showed similar positive associations. Additionally, these findings were robust in sensitivity analyses and broadly consistent across subgroups.

CONCLUSION

Our study suggest that preconception and first-trimester PM₁₀ exposures are related to increased risks of polydactyly and syndactyly.