Perinatal mortality in pregnancies with omphalocele: data from the Chinese national birth defects monitoring network, 1996-2006

Temporal trends in the prevalence of major birth defects in China: a nationwide population-based study from 2007 to 2021

BACKGROUND

Birth defects constitute a significant public health issue worldwide, yet there is a lack of comprehensive population-based data for the Chinese population.

METHODS

We analyzed data from the China National Population-based Birth Defects Surveillance System from 2007 to 2021, we calculated the prevalence rates of selected birth defects, stratified by maternal residence, geographic region, maternal age, and infant sex. The Joinpoint regression model was utilized to assess trends and annual percent changes in prevalence.

RESULTS

From 2007 to 2021, significant downward trends in prevalence were observed for neural tube defects (NTDs), hydrocephalus, cleft lip with or without palate (CL/P), limb reduction defects (LRD), omphalocele, Down syndrome, and tetralogy of Fallot (TOF). Conversely, upward trends were identified for hypospadias, cleft palate (CP), microtia/anotia, polydactyly, syndactyly, ventricular septal defect (VSD), atrial septal defect/patent foramen ovale (ASD/PFO), and patent ductus arteriosus (PDA). Younger mothers exhibited a higher prevalence of hydrocephalus, gastroschisis, CL/P, and polydactyly, while anotia/microtia, Down syndrome, and congenital heart diseases (CHDs) were more common in mothers aged 35 years or older. Significant variations in the prevalence of anencephalus, spina bifida, CL/P, anorectal atresia/stenosis, hypospadias, polydactyly, syndactyly, VSD, ASD/PFO, and PDA were found across different maternal residences and geographic regions.

CONCLUSION

This study highlights the diverse trends and prevalence patterns of major birth defects, underscoring the necessity for defect-specific public health interventions.

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.

Fetal deaths from birth defects in Hunan Province, China, 2016-2020

To describe the fetal death rate of birth defects (including a broad range of specific defects) and to explore the relationship between fetal deaths from birth defects and a broad range of demographic characteristics. Data was derived from the birth defects surveillance system in Hunan Province, China, 2016-2020. Fetal death refers to the intrauterine death of a fetus at any time during the pregnancy, including medical termination of pregnancy. Fetal death rate is the number of fetal deaths per 100 births (including live births and fetal deaths) in a specified group (unit: %). The fetal death rate of birth defects with 95% confidence intervals (CI) was calculated by the log-binomial method. Crude odds ratios (ORs) were calculated to examine the relationship between each demographic characteristic and fetal deaths from birth defects. This study included 847,755 births, and 23,420 birth defects were identified. A total of 11,955 fetal deaths from birth defects were identified, with a fetal death rate of 51.05% (95% CI 50.13-51.96). 15.78% (1887 cases) of fetal deaths from birth defects were at a gestational age of < 20 weeks, 59.05% (7059 cases) were at a gestational age of 20-27 weeks, and 25.17% (3009 cases) were at a gestational age of ≥ 28 weeks. Fetal death rate of birth defects was higher in females than in males (OR = 1.25, 95% CI 1.18-1.32), in rural than in urban areas (OR = 1.43, 95% CI 1.36-1.50), in maternal age 20-24 years (OR = 1.35, 95% CI 1.25-1.47), and ≥ 35 years (OR = 1.19, 95% CI 1.11-1.29) compared to maternal age of 25-29 years, in diagnosed by chromosomal analysis than ultrasound (OR = 6.24, 95% CI 5.15-7.55), and lower in multiple births than in singletons (OR = 0.41, 95% CI 0.36-0.47). The fetal death rate of birth defects increased with the number of previous pregnancies (χ2trend = 49.28, P < 0.01), and decreased with the number of previous deliveries (χ2trend = 4318.91, P < 0.01). Many fetal deaths were associated with birth defects. We found several demographic characteristics associated with fetal deaths from birth defects, which may be related to the severity of the birth defects, economic and medical conditions, and parental attitudes toward birth defects.

Prevalence and death rate of birth defects from population-based surveillance in Hunan Province, China, 2010-2020

To describe the prevalence and death rate of birth defects from population-based surveillance in Hunan Province, China. Data were obtained from the population-based Birth Defects Surveillance System in Hunan Province, China (2010-2020). The surveillance population included all live births, stillbirths, infant deaths, and legal terminations of pregnancy from 28 weeks of gestation to 42 days after birth between 2010 and 2020 when the mother resided in the surveillance area (Liuyang County and Shifeng District, Hunan Province). The prevalence of birth defects is the number of birth defects per 1000 infants (‰). The death rate of birth defects is the number of deaths attributable to birth defects per 100 birth defects (%). The prevalence and death rate with 95% confidence intervals (CI) were calculated by the log-binomial method. Crude odds ratios (ORs) were calculated to examine the association of each demographic characteristic with birth defects. Our study included 228,444 infants, and 4453 birth defects were identified, with a prevalence of 19.49‰ (95%CI 18.92-20.07). Congenital heart defects were the most common specific defects (5.29‰), followed by limb defects (4.01‰). Birth defects were more common in males than females (22.34‰ vs. 16.26‰, OR = 1.38, 95%CI 1.30-1.47), in premature birth than not (91.82‰ vs. 16.14‰, OR = 6.16, 95%CI 5.72-6.65), in birth weight < 2500 g (98.26‰ vs. 16.22‰, OR = 6.61, 95%CI 6.11-7.15) or > 4000 g (19.48‰ vs. 16.22‰, OR = 1.21, 95%CI 1.03-1.42) than birth weight 2500-4000 g, in hospitalized deliveries than other institutions (22.16‰ vs. 11.74‰, OR = 1.91, 95%CI 1.76-2.07), in multiple births than singletons (28.50‰ vs. 19.28‰, OR = 1.49, 95%CI 1.27-1.76), in maternal age < 20 years (26.33‰ vs. 18.69‰, OR = 1.42, 95%CI 1.15-1.76) or >  = 35 years (24.31‰ vs. 18.69‰, OR = 1.31, 95%CI 1.18-1.45) than maternal age 25-29 years, and in number of pregnancies >  = 4 (22.91‰ vs. 18.92‰, OR = 1.22, 95%CI 1.10-1.35) than the first pregnancy. A total of 747 deaths attributable to birth defects were identified, including 603 (80.72%) stillbirths, 75 (10.04%) deaths within 7 days after birth, 46 (6.16%) deaths in 7-27 days after birth, 23 (3.08%) deaths in 28-42 days after birth. The death rate of birth defects was 16.78% (95%CI 15.57-17.98). Deaths attributable to birth defects accounted for 51.09% (747/1462) of all deaths. Central nervous system defects had the highest death rate (90.27%), and neonatal genetic metabolic defects had the lowest death rate (0.39%). In summary, we have described the prevalence and epidemiology of birth defects from population-based surveillance in Hunan Province, China, 2010-2020. There were differences in the prevalence and death rate of birth defects between population-based surveillance and hospital-based surveillance.

Perinatal deaths attributable to congenital heart defects in Hunan Province, China, 2016-2020

OBJECTIVE

To explore the association between demographic characteristics and perinatal deaths attributable to congenital heart defects (CHDs).

METHODS

Data were obtained from the Birth Defects Surveillance System of Hunan Province, China, 2016-2020. The surveillance population included fetuses and infants from 28 weeks of gestation to 7 days after birth whose mothers delivered in the surveillance hospitals. Surveillance data included demographic characteristics such as sex, residence, maternal age, and other key information, and were used to calculate the prevalence of CHDs and perinatal mortality rates (PMR) with 95% confidence intervals (CI). Multivariable logistic regression analysis (method: Forward, Wald, α = 0.05) and adjusted odds ratios (ORs) were used to identify factors associated with perinatal deaths attributable to CHDs.

RESULTS

This study included 847755 fetuses, and 4161 CHDs were identified, with a prevalence of 0.49% (95%CI: 0.48-0.51). A total of 976 perinatal deaths attributable to CHDs were identified, including 16 (1.64%) early neonatal deaths and 960 (98.36%) stillbirths, with a PMR of 23.46% (95%CI: 21.98-24.93). In stepwise logistic regression analysis, perinatal deaths attributable to CHDs were more common in rural areas than urban areas (OR = 2.21, 95%CI: 1.76-2.78), more common in maternal age <20 years (OR = 2.40, 95%CI: 1.05-5.47), 20-24 years (OR = 2.13, 95%CI: 1.46-3.11) than maternal age of 25-29 years, more common in 2 (OR = 1.60, 95%CI: 1.18-2.18) or 3 (OR = 1.43, 95%CI: 1.01-2.02) or 4 (OR = 1.84, 95%CI: 1.21-2.78) or > = 5 (OR = 2.02, 95%CI: 1.28-3.18) previous pregnancies than the first pregnancy, and more common in CHDs diagnosed in > = 37 gestional weeks (OR = 77.37, 95%CI: 41.37-144.67) or 33-36 gestional weeks (OR = 305.63, 95%CI: 172.61-541.15) or < = 32 gestional weeks (OR = 395.69, 95%CI: 233.23-671.33) than diagnosed in postnatal period (within 7 days), and less common in multiple births than singletons (OR = 0.48, 95%CI: 0.28-0.80).

CONCLUSIONS

Perinatal deaths were common in CHDs in Hunan in 2016-2020. Several demographic characteristics were associated with perinatal deaths attributable to CHDs, which may be summarized mainly as economic and medical conditions, severity of CHDs, and parental attitudes toward CHDs.

Perinatal deaths from birth defects in Hunan Province, China, 2010-2020

OBJECTIVE

To describe the perinatal mortality rate (PMR) of birth defects and to define the relationship between birth defects (including a broad range of specific defects) and a broad range of factors.

METHODS

Data were obtained from the Birth Defects Surveillance System in Hunan Province, China, 2010-2020. The prevalence rate (PR) of birth defects is the number of birth defects per 1000 fetuses (births and deaths at 28 weeks of gestation and beyond). PMR is the number of perinatal deaths per 100 fetuses. PR and PMR with 95% confidence intervals (CI) were calculated using the log-binomial method. Chi-square trend tests (χ2trend) were used to determine trends in PR and PMR by year, maternal age, income, education level, parity, and gestational age of termination. Crude odds ratios (ORs) were calculated to examine the association of each maternal characteristic with perinatal deaths attributable to birth defects.

RESULTS

Our study included 1,619,376 fetuses, a total of 30,596 birth defects, and 18,212 perinatal deaths (including 16,561 stillbirths and 1651 early neonatal deaths) were identified. The PR of birth defects was 18.89‰ (95%CI: 18.68-19.11), and the total PMR was 1.12%(95%CI: 1.11-1.14). Birth defects accounted for 42.0% (7657 cases) of perinatal deaths, and the PMR of birth defects was 25.03%. From 2010 to 2020, the PMR of birth defects decreased from 37.03% to 2010 to 21.00% in 2020, showing a downward trend (χ2trend = 373.65, P < 0.01). Congenital heart defects caused the most perinatal deaths (2264 cases); the PMR was 23.15%. PMR is highest for encephalocele (86.79%). Birth defects accounted for 45.01% (7454 cases) of stillbirths, and 96.16% (7168 cases) were selective termination of pregnancy. Perinatal deaths attributable to birth defects were more common in rural than urban areas (31.65% vs. 18.60%, OR = 2.03, 95% CI: 1.92-2.14) and in females than males (27.92% vs. 22.68%, OR = 1.32, 95% CI: 1.25-1.39). PMR of birth defects showed downward trends with rising maternal age (χ2trend = 200.86, P < 0.01), income (χ2trend = 54.39, P < 0.01), maternal education level (χ2trend = 405.66, P < 0.01), parity (χ2trend = 85.11, P < 0.01) and gestational age of termination (χ2trend = 15297.28, P < 0.01).

CONCLUSION

In summary, birth defects are an important cause of perinatal deaths. Rural areas, female fetuses, mothers with low maternal age, low income, low education level, low parity, and low gestational age of termination were risk factors for perinatal deaths attributable to birth defects. Future studies should examine the mechanisms. Our study is helpful for intervention programs to reduce the PMR of birth defects.

Epidemiology and prevalence of pulmonary sequestration in Chinese population, 2010-2019

BACKGROUND

Pulmonary sequestration (PS) is the second common congenital lung malformation and has been known for over 150 years. However, there is a scarcity of epidemiological studies on it. This study aimed to characterize the epidemiology of pulmonary sequestration in Chinese population in the recent decade by using a nationwide database.

METHODS

Using data from the Chinese Birth Defects Monitoring Network during 2010-2019, the prevalence rates for PS were calculated by birth year, maternal age, residence area, geographical region, and infant sex. Variations in prevalence and changes over time were further examined. Other variables of interest for analysis included the pregnancy outcomes of affected infants, the prenatal diagnosis, and the co-occurring anomalies of PS cases.

RESULTS

During the study period, we identified an average prevalence rate of 0.31, 0.11, and 0.42 per 10,000 live and still births for the isolated, non-isolated, and overall PS, respectively. An upward trend was observed for each category of PS. The prevalence rates varied significantly by maternal age (< 20 years, 0.34/10,000; 20-24 years, 0.33/10,000; 25-29 years, 0.45/10,000; 30-34 years, 0.46/10,000; ≥ 35 years, 0.36/10,000), residence area (urban vs. rural, 0.51/10,000 vs. 0.30/10,000), geographical region (western, 0.33/10,000; eastern, 0.49/10,000; central, 0.43/10,000), and by infant sex (male vs. female, 0.45/10,000 vs. 0.38/10,000). Non-isolated PS cases were more likely born prematurely than isolated cases (15.29% vs. 7.83%). 40.28% and 33.80% of non-isolated cases were accompanied by additional respiratory, and circulatory system malformations, respectively.

CONCLUSIONS

The study presents for the first time the prevalence of pulmonary sequestration in Chinese population. The rising prevalence and relatively poor perinatal outcome of affected fetuses or newborns indicate the necessity to improve perinatal management of PS.

Anatomy and embryology of abdominal wall defects

Abdominal wall defects are one of the most frequently encountered human congenital anomalies. They are seen in as many as 1 in 2,000 live births with evidence to suggest that their incidence is increasing. While often discussed together abdominal wall defects consist mainly of two entities namely gastroschisis and omphalocele. There are marked differences in their theories of embryo-pathogenesis, clinical presentation/anatomy and overall outcomes. There is no clear consensus explaining the precise embryological mechanisms leading to the development of abdominal wall defects. Many clinicians and embryologists have attempted to explain the genesis of congenital abdominal wall defects because of failure of progression of various phases of normal embryonic development. This review summarizes the mechanisms involved in normal and abnormal development of the ventral abdominal wall leading to the development of gastroschisis and omphalocele.

Epidemiology of Birth Defects in Eastern China and the Associated Risk Factors

BACKGROUND This study aimed to survey the overall situation of birth defects (BDs) among citizens of Hangzhou, China, and the risk factors of different BD types. MATERIAL AND METHODS We collected the data of 4349 perinatal infants with BDs in Hangzhou. The potentially associated risk factors of BDs were recorded and logistic regression analysis was used to predict the high incidence of BDs. RESULTS Among all perinatal infants with BDs, there were 4105 (94.3%) single births, 225 (5.2%) twin births, and 10 (0.2%) multiple births. In clinical outcomes, there were 2477 (57.0%) live births, 1806 (41.5%) dead fetuses, and 11 (0.3%) stillbirths. Down syndrome ranked first, accounting for 30.7% of the total births, followed by cleft lip and polydactyly. Low family income, nulliparity, high parity, high education level, and taking contraceptives in early pregnancy were found to be risk factors of Down syndrome. Low parity, low education level, and pesticide exposure were found to be risk factors of cleft lip. For polydactyly, young age of the mother and a parity above 0 were identified as risk factors. CONCLUSIONS Different risks factors can influence BD development and potentially help to predict specific BD types, such as demographic features and harmful exposure in early pregnancy.

Can perinatal outcomes of fetal omphalocele be improved at a tertiary center in South China?

OBJECTIVE

To assess the efficacy of positive feedback closed-loop management system (PFCMS) protocol in influencing parents' decision about pregnancy continuation in pregnancies diagnosed with omphalocele.

METHODS

This was a retrospective cohort study of patients who were diagnosed with fetal omphalocele prior to 20 weeks' gestation by ultrasound and were referred to Fetal Care Center at a mainland Chinese medical center during an 11-year period. Two management strategies were offered during the two stages of the study period: a single consultant with a routine protocol and a multidisciplinary support team with PFCMS, respectively. We analyzed the two protocols influencing parents' decision about pregnancy continuation.

RESULTS

Forty-nine patients diagnosed with fetal omphalocele were included in this study. In Group A including 16 patients with routine protocol during the first stage of the study period, the majority opted for termination, and only five continued the pregnancy. In Group B including 33 patients with PFCMS during the second stage of the study period, less than one third chose TOP, and 23 ended in live births. There was a significantly lower TOP rate in patients treated with the PFCMS protocol.

CONCLUSION

The PFCMS protocol may be an efficient approach in managing pregnancies complicated by omphalocele, which may help in preventing unnecessary pregnancy terminations.

Omphalocele in Finland from 1993 to 2014: Trends, Prevalence, Mortality, and Associated Malformations-A Population-Based Study

INRODUCTION

 The aim of this study is to assess the changes in prevalence, mortality and termination pregnancy of omphalocele, and to identify associated anomalies.

MATERIALS AND METHODS

 A population-based nationwide register study. All cases with omphalocele were identified in the Finnish Register of Congenital Malformations and the Care Register for Health Care from 1993 to 2014 including live births, stillbirths, and terminations of pregnancy due to fetal anomalies. Associated anomalies were recorded and analyzed, and perinatal and infant mortality and prevalence were calculated.

RESULTS

 There were 600 cases with omphalocele including 229 live births, 39 stillbirths, and 332 (55%) abortions. Birth prevalence in Finland was 1.96 per 10,000 births with no consistent trend over time. However, total prevalence was much higher (4.71/10,000) because more than half of these families chose option for the termination of pregnancy. Omphalocele is often complicated with other anomalies; most commonly chromosomal abnormalities (9.3%), heart defects (6.3%), central nervous system anomalies (3.0%), gastrointestinal, and urogenital malformations (both 2.0%). Proportion of chromosomal and central nervous system abnormalities were even higher in terminated pregnancies. Overall infant mortality was 22%. Total 1-year survival rates for isolated omphalocele, cases with multiple anomalies and neonates with chromosomal defects were 80, 88, and 17%, respectively.

CONCLUSION

 Omphalocele is a rare congenital anomaly, often associated with other malformations. Our data suggest that isolated cases may be more common than previously thought. In the absence of chromosomal defects, survival is reasonably good. Regardless, more than half of these pregnancies are often terminated.

Abdominal Wall Defects-Current Treatments

Gastroschisis and omphalocele reflect the two most common abdominal wall defects in newborns. First postnatal care consists of defect coverage, avoidance of fluid and heat loss, fluid administration and gastric decompression. Definitive treatment is achieved by defect reduction and abdominal wall closure. Different techniques and timings are used depending on type and size of defect, the abdominal domain and comorbidities of the child. The present review aims to provide an overview of current treatments.

Long-term hospital admissions and surgical treatment of children with congenital abdominal wall defects: a population-based study

Congenital abdominal wall defects, namely, gastroschisis and omphalocele, are rare congenital malformations with significant morbidity. The long-term burden of these anomalies to families and health care providers has not previously been assessed. We aimed to determine the need for hospital admissions and the requirement for surgery after initial admission at birth. For our analyses, we identified all infants with either gastroschisis (n=178) or omphalocele (n=150) born between Jan 1, 1998, and Dec 31, 2014, in the Register of Congenital Malformations. The data on all hospital admissions and operations performed were acquired from the Finnish Hospital Discharge Register between Jan 1, 1998, and Dec 31, 2015, and compared to data on the whole Finnish pediatric population (0.9 million) live born 1993-2008. Patients with gastroschisis and particularly those with omphalocele required hospital admissions 1.8 to 5.7 times more than the general pediatric population (p<0.0001). Surgical interventions were more common among omphalocele than gastroschisis patients (p=0.013). At the mean follow-up of 8.9 (range 1.0-18.0) years, 29% (51/178) of gastroschisis and 30% (45/150) of omphalocele patients required further abdominal surgery after discharge from the neonatal admission.Conclusion: Patients with gastroschisis and especially those with omphalocele, are significantly more likely than the general pediatric population to require hospital care. Nevertheless, almost half of the patients can be treated without further surgery, and redo abdominal surgery is only required in a third of these children. What is Known: • Gastroschisis and omphalocele are congenital malformations with significant morbidity • There are no reports on the long-term need for hospital admissions and surgery in these children What is New: • Patients with abdominal wall defects are significantly more likely than the general pediatric population to require hospital care • Almost half of the patients can be treated without further surgery, and abdominal redo operations are only required in a third of these children.

A multi-country study of prevalence and early childhood mortality among children with omphalocele

BACKGROUND

Omphalocele is the second most common abdominal birth defect and often occurs with other structural and genetic defects. The objective of this study was to determine omphalocele prevalence, time trends, and mortality during early childhood, by geographical region, and the presence of associated anomalies.

METHODS

We conducted a retrospective study with 23 birth defect surveillance systems in 18 countries who are members of the International Clearinghouse for Birth Defects Surveillance and Research that submitted data on cases ascertained from 2000 through 2012, approximately 16 million pregnancies were surveyed that resulted in live births, stillbirths, or elective terminations of pregnancy for fetal anomalies (ETOPFA) and cases with omphalocele were included. Overall prevalence and mortality rates for specific ages were calculated (day of birth, neonatal, infant, and early childhood). We used Kaplan-Meier estimates with 95% confidence intervals (CI) to calculate cumulative mortality and joinpoint regression for time trend analyses.

RESULTS

The prevalence of omphalocele was 2.6 per 10,000 births (95% CI: 2.5, 2.7) and showed no temporal change from 2000-2012 (average annual percent change = -0.19%, p = .52). The overall mortality rate was 32.1% (95% CI: 30.2, 34.0). Most deaths occurred during the neonatal period and among children with multiple anomalies or syndromic omphalocele. Prevalence and mortality varied by registry type (e.g., hospital- vs. population-based) and inclusion or exclusion of ETOPFA.

CONCLUSIONS

The prevalence of omphalocele showed no temporal change from 2000-2012. Approximately one-third of children with omphalocele did not survive early childhood with most deaths occurring in the neonatal period.

Investigating the use of ultrasonography for the antenatal diagnosis of structural congenital anomalies in low-income and middle-income countries: a systematic review

BACKGROUND

Congenital anomalies are the fifth leading cause of under-5 mortality globally. The greatest burden is faced by those in low/middle-income countries (LMICs), where over 95% of deaths occur. Many of these deaths may be preventable through antenatal diagnosis and early intervention. This systematic literature review investigates the use of antenatal ultrasound to diagnose congenital anomalies and improve the health outcomes of infants in LMICs.

METHODS

A systematic literature review was conducted using three search strings: (1) structural congenital anomalies; (2) LMICs; and (3) antenatal diagnosis. The search was conducted on the following databases: Medline, Embase, PubMed and the Cochrane Library. Title, abstract and full-text screening was undertaken in duplicate by two reviewers independently. Consensus among the wider authorship was sought for discrepancies. The primary analysis focused on the availability and effectiveness of antenatal ultrasound for diagnosing structural congenital anomalies. Secondary outcomes included neonatal morbidity and mortality, termination rates, referral rates for further antenatal care and training level of the ultrasonographer. Relevant policy data were sought.

RESULTS

The search produced 4062 articles; 97 were included in the review. The median percentage of women receiving an antenatal ultrasound examination was 50.0% in African studies and 90.7% in Asian studies (range 6.8%-98.8%). Median detection rates were: 16.7% Africa, 34.3% South America, 34.7% Asia and 47.3% Europe (range 0%-100%). The training level of the ultrasound provider may affect detection rates. Four articles compared morbidity and mortality outcomes, with inconclusive results. Significant variations in termination rates were found (0%-98.3%). No articles addressed referral rates.

CONCLUSION

Antenatal detection of congenital anomalies remains highly variable across LMICs and is particularly low in sub-Saharan Africa. Further research is required to investigate the role of antenatal diagnosis for improving survival from congenital anomalies in LMICs.

PROSPERO REGISTRATION NUMBER

CRD42019105620.

Major abdominal wall defects in the low- and middle-income setting: current status and priorities

Major congenital abdominal wall defects (gastroschisis and omphalocele) may account for up to 21% of emergency neonatal interventions in low- and middle-income countries. In many low- and middle-income countries, the reported mortality of these malformations is 30-100%, while in high-income countries, mortality in infants with major abdominal wall reaches less than 5%. This review highlights the challenges faced in the management of newborns with major congenital abdominal wall defects in the resource-limited setting. Current high-income country best practice is assessed and opportunities for appropriate priority setting and collaborations to improve outcomes are discussed.

Gestational Outcomes of Pregnancies with Prenatally Detected Gastroschisis and Omphalocele

Objective: To evaluate and compare the outcomes of pregnancies with prenatally detected gastroschisis and omphalocele. Materials and Methods: We retrospectively evaluated prenatally detected gastroschisis and omphalocele cases. Cases were compared in terms of maternal demographic and clinical characteristics as well as pregnancy and neonatal outcomes. Results: This study consisted of 17 gastroschisis and 30 omphalocele cases. Only one case with gastroschisis was terminated due to additional severe limb deformities. Seventeen out of 30 cases of omphalocele were terminated for various reasons (56.7%). All patients with gastroschisis had surgical repair, while 8 out of 13 omphalocele cases had surgery. One patient with an omphalocele died after surgery due to sepsis. Six cases of gastroschisis also died in the neonatal period due to various reasons (6/16, 37.5%). Conclusion: Additional genetic disorders are more frequent in those with omphalocele cases, and they are more frequently terminated during gestation that the gastroschisis fetuses.

Insights into embryology and development of omphalocele

Congenital abdominal wall defects are one of the most common human birth defects with an incidence of about 1 in 2000 live births. While often discussed together abdominal wall defects consist mainly of two distinct entities namely gastroschisis and omphalocele. There is no clear consensus explaining the precise embryological mechanisms leading to the development of an omphalocele. Many clinicians and embryologists have attempted to explain congenital malformation as a result of failure of progression of normal embryonic development. This review summarizes the mechanisms involved in normal and abnormal development of the ventral abdominal wall.

Evaluating the time trends in prevalence of exomphalos in 14 cities of Liaoning province, 2006 to 2015

To evaluate time trends of exomphalos prevalence using a large population-based study with cases identified by the Liaoning Birth Defects Registry including 14 cities over the course of a 10-year period. Exomphalos prevalence, percent change, annual percent change (APC), and contribution rates of each city were calculated. Additionally, epidemiological characteristics of this malformation were described. We observed 516 cases of exomphalos among 3,248,954 live births. Birth prevalence of exomphalos was 1.59 per 10,000 live births with non-significant change during the observational period (APC = −1.19%, P = 0.48). However, significantly decreasing trends were noticed in three cities: Fushun (APC = −9.15%, P = 0.03), Benxi (APC = −11.49%, P = 0.05), and Yingkou (APC = −16.47%, P = 0.04), contributing 62.77% of the decreasing trend of overall prevalence. The mean maternal age, gestational age, and birth weight was 28.4 years (standard deviation [SD], 6.1 years), 25.6 weeks (SD, 8.6 weeks), and 1236.2 gram (SD, 1164.4 gram). For time of diagnosis, 79.8% (n = 412) cases were diagnosed during pregnancy. In summary, the prevalence of exomphalos in Liaoning province did not change remarkably during 2006 to 2015. Future studies are warranted to investigate the risk factors and create prevention strategies for this disease.

Long-term trends and seasonality of omphalocele during 1996-2010 in China: a retrospective analysis based on the hospital-based birth defects surveillance system

BACKGROUND

Little is known about secular trends and seasonal variation in the birth prevalence of omphalocele in China. This study aimed to explore the long-term trends and seasonality of this birth defect, to provide insight into the etiology and prevention of omphalocele.

METHODS

A retrospective analysis of all births with omphalocele (1322 cases in 8.8 million births) registered in the hospital-based Chinese Birth Defects Monitoring Network between January 1996 and September 2010. Negative binomial cyclical regression models were used to analyze the long-term trends and seasonal fluctuations of omphalocele occurrence in the southern and northern regions and urban and rural areas of China.

RESULTS

The total prevalence of omphalocele was 1.50 cases (95% confidence interval (CI): 1.42-1.58) per 10,000 births. There was no significant secular trend of omphalocele occurrence in China between 1996 and 2010. The observed prevalence of omphalocele in rural areas was 2.03-2.54 cases per 10,000 births between May and August, which was higher than that observed in other months. The highest prevalence of births with omphalocele in rural areas occurred at the end of June; on average, the prevalence of omphalocele at that time point increased by 20% (95% CI: 6-35%) compared with other months.

CONCLUSIONS

There were no long-term trends found for occurrence of omphalocele in China between 1996 and 2010; however, seasonality was observed for omphalocele in women living in rural areas. These results may help generate hypotheses for further study of environmental factors that vary by season.