Non-genetic risk factors for gastroschisis

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.

Genitourinary infection and gastroschisis: A systematic review and meta-analysis

BACKGROUND

Gastroschisis is a congenital anomaly of the umbilical ring with increasing prevalence, especially amongst younger mothers. There is increasing evidence that exposure to genitourinary infections (GUTI) may play an important role in the etiology of gastroschisis. This systematic review and meta-analysis aimed to identify, appraise, and summarize the literature on exposure to GUTI and gastroschisis.

METHODS

Six electronic databases (MEDLINE, EMBASE, Web of Science, Scopus, Cochrane Library electronic databases, and Prospero) were searched using a comprehensive search strategy. Citations and cited articles for all included studies were searched. Peer-reviewed, quantitative studies reporting an association of urinary tract infections (UTI) and/or sexually transmitted infections (STI) with gastroschisis were included. Prospero registration CRD42022377420.

RESULTS

A total of 2392 papers were identified via the searches of which 15 met our inclusion criteria and were included after title and abstract and full text screening. The study period for included studies ranged from 1995 to 2016, most were from the USA. Four studies considering exposure to STIs and five to UTIs were eligible to progress to meta-analysis. Meta-analysis identified a significantly increased risk of gastroschisis in association with periconceptional exposure to UTI [OR 1.54 (95% CI 1.29, 1.8)], STI [OR 1.4 (95% CI 1.01, 1.79)].

CONCLUSIONS

Periconceptional exposure to GUTI is associated with an increased risk of gastroschisis. The prevention and timely treatment of GUTI amongst women of childbearing age may help to reduce the occurrence of gastroschisis.

Medication use during pregnancy and the risk of gastroschisis: a systematic review and meta-analysis of observational studies

OBJECTIVES

The aetiology of gastroschisis is considered multifactorial. We conducted a systematic review and meta-analysis to assess whether the use of medications during pregnancy, is associated with the risk of gastroschisis in offspring.

METHODS

PubMed, EMBASE, and Scopus were searched from 1st January 1990 to 31st December 2020 to identify observational studies examining the association between medication use during pregnancy and the risk of gastroschisis. The Newcastle-Ottawa Scale was used for the quality assessment of the individual studies. We pooled adjusted measures using a random-effect model to estimate relative risk [RR] and the 95% confidence interval [CI]. I2 statistic for heterogeneity and publication bias was calculated.

RESULTS

Eighteen studies providing data on 751,954 pregnancies were included in the meta-analysis. Pooled RRs showed significant associations between aspirin (RR 1.66, 95% CI 1.16-2.38; I2 = 58.3%), oral contraceptives (RR 1.52, 95% CI 1.21-1.92; I2 = 22.0%), pseudoephedrine and phenylpropanolamine (RR 1.51, 95% CI 1.16-1.97; I2 = 33.2%), ibuprofen (RR 1.42, 95% CI 1.26-1.60; I2 = 0.0%), and gastroschisis. No association was observed between paracetamol and gastroschisis (RR 1.16, 95% CI 0.96-1.41; I2 = 39.4%).

CONCLUSIONS

These results suggest that the exposure in the first trimester of pregnancy to over the counter medications (OTC) such as aspirin, ibuprofen, pseudoephedrine and phenylpropanolamine as well as to oral contraceptives, was associated with an increased risk of gastroschisis. However, these associations are significant only in particular subgroups defined by geographic location, adjustment variables and type of control. Therefore, further research is needed to investigate them as potential risk factors for gastroschisis, to assess their safety in pregnancy and to develop treatment strategies to reduce the risk of gastroschisis in offspring. PROSPERO registration number: CRD42021287529.

Is gastroschisis associated with county-level socio-environmental quality during pregnancy?

BACKGROUND

Gastroschisis prevalence more than doubled between 1995 and 2012. While there are individual-level risk factors (e.g., young maternal age, low body mass index), the impact of environmental exposures is not well understood.

METHODS

We used the U.S. Environmental Protection Agency's Environmental Quality Index (EQI) as a county-level estimate of cumulative environmental exposures for five domains (air, water, land, sociodemographic, and built) and overall from 2006 to 2010. Adjusted odds ratios (aOR) and 95% confidence interval (CI) were estimated from logistic regression models between EQI tertiles (better environmental quality (reference); mid; poorer) and gastroschisis in the National Birth Defects Prevention Study from births delivered between 2006 and 2011. Our analysis included 594 cases with gastroschisis and 4105 infants without a birth defect (controls).

RESULTS

Overall EQI was modestly associated with gastroschisis (aOR [95% CI]: 1.29 [0.98, 1.71]) for maternal residence in counties with poorer environmental quality, compared to the reference (better environmental quality). Within domain-specific indices, only the sociodemographic domain (aOR: 1.51 [0.99, 2.29]) was modestly associated with gastroschisis, when comparing poorer to better environmental quality.

CONCLUSIONS

Future work could elucidate pathway(s) by which components of the sociodemographic domain or possibly related psychosocial factors like chronic stress potentially contribute to risk of gastroschisis.

Mexican-American Women's Lifelong Residence in the United States Is Associated with an Increased Risk of Gastroschisis: A Population-Based Study

OBJECTIVE

To determine whether nativity is associated with abdominal wall defects among births to Mexican-American women.

STUDY DESIGN

Using a cross-sectional, population-based design, stratified and multivariable logistic regression analyses were performed on the 2014-2017 National Center for Health Statistics live-birth cohort dataset of infants of US-born (n = 1 398 719) and foreign-born (n = 1 221 411) Mexican-American women.

RESULTS

The incidence of gastroschisis was greater among births to US-born compared with Mexico-born Mexican-American women: 36.7/100 000 vs 15.5/100 000, RR = 2.4 (2.0, 2.9). US-born (compared with Mexico-born) Mexican-American mothers had a greater percentage of teens and cigarette smokers, P < .0001. In both subgroups, gastroschisis rates were greatest among teens and decreased with advancing maternal age. Adjusting for maternal age, parity, education, cigarette smoking, pre-pregnancy body mass index, prenatal care usage, and infant sex), OR of gastroschisis for US-born (compared with Mexico-born) Mexican-American women was 1.7 (95% CI 1.4-2.0). The population attributable risk of maternal birth in the US for gastroschisis equaled 43%. The incidence of omphalocele did not vary by maternal nativity.

CONCLUSIONS

Mexican-American women's birth in the US vs Mexico is an independent risk factor for gastroschisis but not omphalocele. Moreover, a substantial proportion of gastroschisis lesions among Mexican-American infants is attributable to factors closely related to their mother's nativity.

Neighborhood-level Socioeconomic Position During Early Pregnancy and Risk of Gastroschisis

BACKGROUND

Neighborhood-level socioeconomic position has been shown to influence birth outcomes, including selected birth defects. This study examines the un derstudied association between neighborhood-level socioeconomic position during early pregnancy and the risk of gastroschisis, an abdominal birth defect of increasing prevalence.

METHODS

We conducted a case-control study of 1,269 gastroschisis cases and 10,217 controls using data from the National Birth Defects Prevention Study (1997-2011). To characterize neighborhood-level socioeconomic position, we conducted a principal component analysis to construct two indices-Neighborhood Deprivation Index (NDI) and Neighborhood Socioeconomic Position Index (nSEPI). We created neighborhood-level indices using census socioeconomic indicators corresponding to census tracts associated with addresses where mothers lived the longest during the periconceptional period. We used generalized estimating equations to estimate odds ratios (ORs) and 95% confidence intervals (CIs), with multiple imputations for missing data and adjustment for maternal race-ethnicity, household income, education, birth year, and duration of residence.

RESULTS

Mothers residing in moderate (NDI Tertile 2 aOR = 1.23; 95% CI = 1.03, 1.48 and nSEPI Tertile 2 aOR = 1.24; 95% CI = 1.04, 1.49) or low socioeconomic neighborhoods (NDI Tertile 3 aOR = 1.28; 95% CI = 1.05, 1.55 and nSEPI Tertile 3 aOR = 1.32, 95% CI = 1.09, 1.61) were more likely to deliver an infant with gastroschisis compared with mothers residing in high socioeconomic neighborhoods.

CONCLUSIONS

Our findings suggest that lower neighborhood-level socioeconomic position during early pregnancy is associated with elevated odds of gastroschisis. Additional epidemiologic studies may aid in confirming this finding and evaluating potential mechanisms linking neighborhood-level socioeconomic factors and gastroschisis.

Association of maternal depression and hypothyroidism with infant gastroschisis: a population-based cohort study in Canada

Gastroschisis has increased globally over recent decades, and this increase has not been explained by identified risk factors. We conducted a population-based study of infants born in Canada, 2004-2020. We used "winter" months (i.e., September through June) and northern areas of residence as indicators of less sunlight/less active lifestyle, while "summer" (i.e., July and August) and southern areas were considered as reference. Rate of gastroschisis for infants conceived in winter (3.4 per 10,000) was higher than for infants conceived in summer (2.2 per 10,000; p < 0.001). Exposure to winter, and northern area, hypothyroidism, substance or tobacco uses and depressive disorder were initially identified as risk factors for gastroschisis. There was a significant interaction between women < 24 years of age and 2-month conception intervals (rate ratio (RR): 1.42 (95% confidence interval [CI] 1.19-1.70). The association of maternal depression (mean ratio 2.19, 95% CI 0.87-3.50, p = 0.001) with infant gastroschisis was mediated by hypothyroidism (mean ratio 1.04, 95% CI 1.01-1.07, p < 0.001), whereas substance use, hypothyroidism, tobacco smoking and gestational diabetes showed 5.5-, 3.1-, 2.7-, and 1.2-fold associations, respectively, with maternal depression. In contrast to the summer conception interval of low gastroschisis risk, an elevated risk of gastroschisis spans the other ten months in association with higher levels of stress adaptation, thermoregulation and metabolism, reproduction, and growth effector hormones. Our findings suggest that periconception depression with mediation by hypothyroidism, may play a causal role in offspring gastroschisis.

Epidemiology of birth defects in teenage pregnancies: Based on provincial surveillance system in eastern China

Background

Healthcare for adolescents and birth defects (BD) prevention are highlighted public health issues. The epidemiology of birth defects in teenage pregnancies has not been studied extensively.

Objectives

To investigate the prevalence trend and spectrum of BDs among teenage mothers.

Methods

This observational study covered all births registered in the BD surveillance system in Zhejiang Province, China, during 2012-2018. The annual change in the prevalence of BDs among adolescent mothers was estimated. Crude relative ratios using the BD categories in teenage pregnancies were calculated and compared with those in women aged 25-29 years.

Results

Overall, 54,571 BD cases among 1,910,977 births were included in this study, resulting in an overall prevalence of 234.64 to 409.07 per 10,000 births from 2012 to 2018 (P _trend < 0.001) in total population. The prevalence of birth defects in teenage pregnancies increased from 247.19 to 387.73 per 10,000 births in 2012-2018 (P _trend = 0.024). The risks of neural tube defects (relative risk [RR] = 3.15, 95% confidence interval [CI] 2.56, 3.87), gastroschisis (RR = 7.02, 95% CI 5.09, 9.69), and multiple birth defects (RR=1.27, 95% CI 1.07, 1.52) were higher in teenage pregnancies than those in women aged 25-29 years.

Conclusions

We found a distinctive spectrum of BDs, with higher proportions of fatal or multiple anomalies in infants born to teenage mothers than in those born to adults aged 25-29 years. These results emphasize the importance of providing adolescents with better access to reproductive and prenatal care.

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.

Gastroschisis annual incidence, mortality, and trends in extreme Southern Brazil

OBJECTIVE

To analyze gastroschisis annual incidence, mortality rates, and trends in the Brazilian state of Rio Grande do Sul from the year 2000 to the year 2017.

METHOD

Population-based study with the analysis of the temporal trend of gastroschisis annual incidence and mortality rates. Data were obtained from the Live Birth Information System and the Mortality Information System, with the analysis performed by polynomial regression modeling.

RESULTS

There were 2,612,532 live births, 705 hospitalizations, and 233 deaths due to gastroschisis. The annual incidence of gastroschisis was 2.69 per 10,000 live births. The annual incidence rate increased by 85% in the total period (p = 0.003), and mortality was 33% in the 2000-2017 period. Maternal age < 25 years was a risk factor for gastroschisis (p < 0.001). Children were more likely to be born weighing < 2,500 g (p < 0.001) and with a gestational age < 37 weeks (p < 0.001). The annual incidence trend was to increase, and the mortality trend was to decrease.

CONCLUSION

Similar to what has been described in several regions/countries, there was a trend showing an 85% increase in the annual incidence of gastroschisis (p = 0.003) and the mortality was 33% with a trend of decreasing (p = 0.002).

The association between wildfire exposure in pregnancy and foetal gastroschisis: A population-based cohort study

BACKGROUND

Global climate change has led to an increase in the prevalence and severity of wildfires. Pollutants released into air, soil and groundwater from wildfires may impact embryo development leading to gastroschisis.

OBJECTIVE

The objective of this study was to determine the association between wildfire exposure before and during pregnancy and the risk of foetal gastroschisis development.

METHODS

This was a retrospective cohort study using The California Office of Statewide Health Planning and Development Linked Birth File linked to The California Department of Forestry and Fire Protection data between 2007 and 2010. Pregnancies complicated by foetal gastroschisis were identified by neonatal hospital discharge ICD-9 code. Pregnancies were considered exposed to wildfire if the mother's primary residence zip code was within 15 miles to the closest edge of a wildfire. The exposure was further stratified by trimester or if exposed within 30 days prior to pregnancy. Multivariable log-binomial regression analyses were performed to estimate the association between wildfire exposure in each pregnancy epoch and foetal gastroschisis.

RESULTS

Between 2007 and 2010, 844,348 (40%) births were exposed to wildfire in California. Compared with births without wildfire exposure, those with first-trimester exposure were associated with higher rates of gastroschisis, 7.8 vs. 5.7 per 10,000 births (adjusted relative risk [aRR] 1.28, 95% confidence interval [CI] 1.07, 1.54). Furthermore, those with prepregnancy wildfire exposure were also found to have higher rates of gastroschisis, 12.5 vs. 5.7 per 10,000 births, (aRR 2.17, 95% CI 1.42, 3.52). In contrast, second- and third-trimester wildfire exposures were not associated with foetal gastroschisis.

CONCLUSIONS

Wildfire exposure within 30 days before pregnancy was associated with more than two times higher risk of foetal gastroschisis, whereas a 28% higher risk was demonstrated if exposure was in the first trimester.

National birth prevalence, associated anomalies and mortality for gastroschisis in Sweden

AIM

An increased incidence has been reported for the congenital abdominal wall defect gastroschisis. The reason for this increasing trend is not known, nor the aetiology. The aim of this study was to examine the national birth prevalence in Sweden, the termination rate, associated anomalies and the mortality of gastroschisis within the cohort.

METHODS

A nationwide, population-based descriptive study of children born with gastroschisis in Sweden between 1/1 1997 and 31/12 2016 was conducted. The cohort was collected from the Swedish Medical Birth Register and the Swedish National Patient Register. Several other national registers were then interlinked to identify outcome data.

RESULTS

The study included 361 cases of gastroschisis, 54% female. The birth prevalence was 1.52 in 10,000 live births. The termination rate was 21%. The mortality within the cohort was 4.4% with a 1-year mortality of 3.9%. Most frequent associated anomalies were gastrointestinal (11.4%), musculoskeletal (9.8%) and cardiovascular anomalies (7.9%).

CONCLUSION

During the 20-year study period, a stable birth prevalence of 1.52 per 10 000 live births was seen in Sweden. The mortality was low, 4.4%, but the termination of pregnancies was high, 21%. Almost one-third had associated congenital anomalies where gastrointestinal anomalies were the most common.

Management of transient central diabetes insipidus with intravenous desmopressin in a premature infant with gastroschisis and septo-optic dysplasia: A case report

Central diabetes insipidus (CDI) may occur in the setting of intracranial abnormalities that affect the hypothalamus-pituitary system. It occurs rarely in neonates, especially in the premature population, and represents a challenging disease process to treat pharmacologically. Little is known regarding the treatment options in premature infants, including dose and route of administration of intravenous desmopressin (DDAVP). We present a case of a late premature male infant with gastroschisis and septo-optic dysplasia who developed transient CDI. He was treated with intravenous DDAVP but required frequent laboratory monitoring and a multidisciplinary approach, and ultimately his CDI resolved. Although there are minimal guidelines regarding the appropriate formulation and dosage of DDAVP for management of CDI in infants, we initiated the lowest dose available and titrated the medication based on close monitoring of urine output and serum sodium levels in order to successfully treat his transient CDI.

Prevalence rates study of selected isolated non-Mendelian congenital anomalies in the Hutterite population of Alberta, 1980-2016

A study of the prevalence rates for selected isolated non-Mendelian congenital anomalies in the Hutterite Brethren of Alberta, Canada was undertaken to further examine longitudinal data in this isolated community that was last reported in 1985 (Lowry et al., 1985), although there are numerous publications on recessive disorders (Boycott et al., 2008; Triggs-Raine et al., 2016). Cases were ascertained from the Alberta Congenital Anomaly Surveillance System for the years 1997-2016. Since our initial results showed some surprising findings in the Hutterite Brethren, such as zero cases of spina bifida, cleft lip and palate, gastroschisis, and omphalocele, and a significant excess of cases with hypospadias, we extended the study to prior years (1980-1996) for selected anomalies. For the extended study period (1980-2016), there was a significant increased prevalence of hypospadias, tetralogy of Fallot and tricuspid atresia in the Hutterite population, and although not statistically significant, zero cases of cleft lip with cleft palate, gastroschisis and omphalocele were confirmed. Further research is needed to determine the precise effects of rural environmental exposures, lifestyle factors, and genetic associations for selected multifactorial congenital anomalies.

Lifestyle and sociodemographic risk factors for gastroschisis: a systematic review and meta-analysis

BACKGROUND

Gastroschisis is strongly associated with young maternal age. This association suggests the need for further investigations on non-genetic risk factors. Identifying these risk factors is a public health priority in order to develop prevention strategies aimed at reducing the prevalence and health consequences in offspring.

OBJECTIVE

To systematically assess and quantitatively synthesise the available epidemiological studies to evaluate the association between non-genetic risk factors and gastroschisis.

METHODS

Literature from PubMed, EMBASE and Scopus was searched for the period 1990-2018. Epidemiological studies reporting risk estimates between lifestyle and sociodemographic risk factors and gastroschisis were included. Two pairs of reviewers independently extracted information on study characteristics following Preferred Reporting Items for Systematic Reviews and Meta-Analyses and MOOSE (Meta-analysis Of Oservational Studies in Epidemiology) guidelines. Relative risk (RR) estimates were calculated across the studies and meta-analysis was performed using random-effects model.

RESULTS

We identified 58 studies. Meta-analyses were conducted on 29 studies. Maternal smoking (RR 1.56, 95% CI 1.40 to 1.74), illicit drug use (RR 2.14, 95% CI 1.48 to 3.07) and alcohol consumption (RR 1.40, 95% CI 1.13 to 1.70) were associated with an increased risk of gastroschisis. A decreased risk among black mothers compared with non-Hispanic white mothers (RR 0.49, 95% CI 0.38 to 0.63) was found. For Hispanic mothers no association was observed.

CONCLUSIONS

Exposure to smoking, illicit drugs and alcohol during pregnancy is associated with an increased risk of gastroschisis. A significantly decreased risk for black mothers was observed. Further epidemiological studies to assess the potential role of other environmental factors are strongly recommended.

PROSPERO REGISTRATION NUMBER

CRD42018104284.

Does overweight before pregnancy reduce the occurrence of gastroschisis?: the Japan Environment and Children's Study

OBJECTIVE

For several observational studies that have reported the factors related to gastroschisis, the target population in these studies was mainly residents of Europe or the US, and there is little data on the Asian population. In this study, we summarised characteristics of Japanese women who delivered infants with gastroschisis, particularly focusing on the pre-pregnancy body mass index (BMI), which was found to be inversely associated with gastroschisis in past studies, because the distribution of BMI is clearly different in Asia and the West.

RESULTS

We used data from a nationwide birth cohort study which recruited pregnant women between 2011 and 2014. Among 92,796 women who delivered singleton live births, the frequency of underweight (pre-pregnancy BMI < 18.5 kg/m2) was 16.2%, reference weight (18.5-24.9 kg/m2) 73.1%, and overweight (≥ 25.0 kg/m2) 10.6%. We identified only 9 infants with gastroschisis, 2 of whose women were underweight (frequency of gastroschisis = 0.01%), 5 were in the reference group (0.01%), and 2 were overweight (0.02%). Of these 9 women, none were aged < 20 years, 2 were aged 20-29 years (frequency = 0.01%), and 7 were aged 30-39 years (0.01%). No reduction in the occurrence of gastroschisis was apparent among Japanese women who were overweight before pregnancy.

A machine learning approach to investigate potential risk factors for gastroschisis in California

BACKGROUND

To generate new leads about risk factors for gastroschisis, a birth defect that has been increasing in prevalence over time, we performed an untargeted data mining statistical approach.

METHODS

Using data exclusively from the California Center of the National Birth Defects Prevention Study, we compared 286 cases of gastroschisis and 1,263 non-malformed, live-born controls. All infants had delivery dates between October 1997 and December 2011 and were stratified by maternal age at birth (<20 and ≥ 20 years). Cases and controls were compared by maternal responses to 183 questions (219 variables) using random forest, a data mining procedure. Variables deemed important by random forest were included in logistic regression models to estimate odds ratios and 95% confidence intervals.

RESULTS

Among women younger than 20, of variables deemed important, there were higher odds observed for higher consumption of chocolate, low intake of iron, acetaminophen use, and urinary tract infections during the beginning of pregnancy. After adjustment, the higher odds remained for low iron intake and a urinary tract infection in the first month of pregnancy. Among women aged 20 or older, of variables deemed important, higher odds were observed for US-born women of Hispanic ethnicity and for parental substance abuse. There were lower odds observed for obese women, women who ate any cereal the month before pregnancy, and those with higher parity.

CONCLUSIONS

We did not discover many previously unreported associations, despite our novel approach to generate new hypotheses. However, our results do add evidence to some previously proposed risk factors.

Insights into the etiology and embryology of gastroschisis

The development of gastroschisis has long remained an area of interest and controversy. Successive theories about its pathogenesis are herein reviewed and discussed. Two historical assumptions, that omphalocele results from a persistent umbilical hernia, and that gastroschisis does not involve the umbilical cord, are dismissed. Therefore, one can envision gastroschisis for what it is, i.e. a ruptured physiological hernia. The causal agents for this intrauterine accident to occur are yet to be determined. Further bowel damage and complications can be explained by the mesenteric insult.

Impact of societal factors and health care delivery systems on gastroschisis outcomes

Care of infants with gastroschisis is associated with a significant burden on health care delivery systems. Mortality rates in patients with gastroschisis have significantly improved over the past few decades. However, the condition is still associated with significant short-term and potentially long-term morbidity. Significant variations in clinical outcomes and resource utilization may be explained by several factors including provider and hospital experience, level of neonatal intensive care, variations in hospital regionalization of care, and differences in healthcare delivery systems. Reviewing and assessing these hospital and healthcare system related factors are paramount in addressing variations in gastroschisis care and improving outcomes for these vulnerable infants.

Gastroschisis and Cumulative Stressor Exposures

BACKGROUND

Gastroschisis, a congenital defect of the abdominal wall, occurs disproportionately more in offspring of young mothers and has been increasing in prevalence over the past decades. A wide range of exposures have been reported in association with an increased gastroschisis risk, independent of mother's age; many have also been correlated with stress responses.

METHODS

We explored cumulative exposures to such stressor exposures among 1,261 mothers of gastroschisis cases and 10,682 mothers of controls in the National Birth Defects Prevention Study (1997-2011). We considered 16 exposures as stressors in the first trimester: fever, genitourinary infection, anti-herpetic medication use, injury, bronchodilator use, cigarette smoking, alcohol intake, illicit drug use, prescription opioid use, oral contraceptive use, interpregnancy interval < 12 months, residential move, aspirin use, ibuprofen use, venlafaxine use, and paroxetine use.

RESULTS

Mothers of cases reported more stressor exposures than controls. For 1, 2, 3, and ≥ 4 stressor exposures compared with none, the age-adjusted odds ratios (95% confidence interval) were 1.3 (1.1, 1.6), 1.7 (1.4, 2.1), 2.5 (2.0, 3.1), and 3.6 (2.9, 4.4), respectively. When we weighted cumulative stress scores according to the magnitude of stressor-specific odds ratios, similar associations were observed. Cumulative stressor exposure did not account for the strong inverse association between age and gastroschisis risk.

CONCLUSIONS

These findings show that gastroschisis risk appears to increase with accumulation of widely different types of exposures, consistent with the hypothesis that stress-induced inflammation might play an etiologic role.

Genetic variants conferring susceptibility to gastroschisis: a phenomenon restricted to the interaction with the environment?

BACKGROUND

Genes involved in gastroschisis have shown a strong interaction with environmental factors. However, less is known about its influence. We aimed to systematically review the genetic associations of gastroschisis, to summarize whether its genetic susceptibility has been restricted to the interaction with the environment, and to identify significant gaps that remain for consideration in future studies.

METHODS

Genetic association studies of gastroschisis published 1980-2017 (PubMed/MEDLINE) were independently searched by two reviewers. Significant SNP-gastroschisis associations were grouped into crude and stratified risks, whereas SNPs were assessed from two or more independent studies. Frequencies, odds ratios, and 95% confidence intervals were pooled using descriptive analysis and Chi-square test accounting for heterogeneity.

RESULTS

Seven eligible articles capturing associations of 14 SNPs from 10 genes for crude risk (including 10 and 4 SNPs with increased and decreased risk, respectively) and 30 SNPs from 14 genes for stratified risk in gastroschisis (including 37 and 14 SNPs with increased and decreased risk, respectively) were identified (Fisher's exact test, P = 0.438). The rs4961 (ADD1), rs5443 (GNB3), rs1042713, and rs1042714 (ADRB2) were significantly associated with gastroschisis.

CONCLUSIONS

Genetic susceptibility in gastroschisis is not restricted to the interaction with the environment and should not be too narrowly focused on environmental factors. We found significant associations with four SNPs from three genes related to blood pressure regulation, which supports a significant role of vascular disruption in the pathogenesis of gastroschisis. Future studies considering gene-gene or gene-environmental interactions are warranted for better understanding the etiology of gastroschisis.

Herpesvirus Infection in Infants with Gastroschisis

BACKGROUND

Gastroschisis is a congenital malformation that has been shown to be more common in younger mothers and appears to be increasing in prevalence in the United States and elsewhere. Epidemiologic data suggest a potential role of infection and recent studies report an association between maternal antibodies to human herpesviruses (HHV) and development of gastroschisis.

METHODS

In this study, we examined newborn bloodspots from 50 children with gastroschisis and 50 healthy controls using a highly sensitive digital droplet polymerase chain reaction assay covering eight human herpesviruses [herpes simplex sirus 1/2, Epstein-Barr virus (HHV-4), cytomegalovirus (HHV-5), HHV-6A/B, HHV-7, and HHV-8], to examine the presence of herpesvirus DNA at birth, which would suggest in utero infection.

RESULTS

One control tested positive for low-level cytomegalovirus infection. We found no evidence of an association between herpesvirus DNA in neonatal blood spots taken at birth and gastroschisis.

CONCLUSIONS

Our results do not support direct involvement of herpesviruses in the etiology of gastroschisis. However, there are several limitations in our study, most notably the known induction of this congenital malformation early in pregnancy and our analysis of blood taken at birth. Therefore, we cannot conclude that herpesviruses play no role in the etiology of gastroschisis and further research is needed to better define this relationship.

Maternal Chlamydia infection during pregnancy among younger mothers and risk of gastroschisis in singleton offspring

BACKGROUND

Prevalence of gastroschisis has been increasing in the United States (US) since 1980s. Genital infection with Chlamydia has also been increasing in prevalence, particularly among younger women. The etiology of gastroschisis is unknown. Ongoing research suggests multiple causal factors may be involved, including Chlamydia infection in mothers during pregnancy.

METHODS

Using birth certificate data from 2014 US vital records, we conducted a population-based case-control study to examine the association between prenatal Chlamydia exposure in young women (16-25 years of age) and gastroschisis in singleton offspring. Cases consisted of live births with gastroschisis, and controls had no major birth defects reported in their birth certificate. Logistic regression analysis was used to estimate crude and adjusted odds ratios (cOR and aOR) and 95% confidence intervals (CI).

RESULTS

There were 809 cases (95.6% were isolated cases) and 1,260,293 controls. Chlamydia during pregnancy was reported in 4.5% of case and 3.6% control mothers (p = .21). Case mothers were significantly more likely to be younger (16-20 years of age) at the time of delivery compared to control mothers (p < .0001). We found no significant association between Chlamydia infection during pregnancy and gastroschisis (cOR = 1.24; 95% CI = 0.89-1.73 and aOR = 1.06; 95% CI: 0.66-1.70).

CONCLUSION

With the caveat of possible misclassification of exposure and outcome variables in birth certificate data, we found no significant association between prenatal exposure to Chlamydia and gastroschisis in the offspring born to younger mothers. Future studies should refine measures by focusing on relevant risk period and biomarkers.

The prevalence of selected major birth defects in the United States

Although collectively they are fairly common, birth defects receive limited attention as a group of outcomes either clinically or from a public health perspective. This article provides an overview of the prevalence, trends and selected socio-demographic risk factors for several major birth defects, including neural tube defects, cranio-facial anomalies, congenital heart defects, trisomies 13, 18, and 21, and gastroschisis and omphalocele. Attention should focus on strengthening existing registries, creating birth defects surveillance programs in states that do not have them, and standardizing registry methods so that broadly national data to monitor these trends are available.

Maternal Antibodies to Herpes Virus Antigens and Risk of Gastroschisis in Offspring

Gastroschisis risk is highest in offspring of young women and is increasing in prevalence, suggesting that exposures that are increasingly common among younger females may be causal. Some infections by viruses in the herpes family are more common in the earlier childbearing years and have been increasing in prevalence over time. Data from the Finnish Maternity Cohort were linked to Finnish malformation and birth registers (1987-2012) for this study, a nested case-control study of mothers of offspring with gastroschisis and age-matched controls. Maternal antibody responses in early pregnancy (mean gestational age = 11.1 weeks) to Epstein Barr virus (EBV), herpes simplex virus types 1 and 2 (HSV-1 and HSV-2), and cytomegalovirus were measured. Conditional logistic regression models were used to estimate odds ratios (and 95% confidence intervals) for high immunoglobulin reactivity. Odds ratios for high immunoglobulin M (IgM) reactivity to EBV-viral capsid antigen and HSV-1 or HSV-2 (as indicators of recent infection) were 2.16 (95% confidence interval (CI): 0.97, 4.79) and 1.94 (95% CI: 0.74, 5.12), respectively. For higher immunoglobulin G (IgG) reactivity to EBV-viral capsid antigen and HSV-2 IgG, odds ratios were 2.16 (95% CI: 0.82, 5.70) and 2.48 (95% CI: 1.50, 4.10), respectively. Reactivities to HSV-1 IgG, cytomegalovirus IgM, or cytomegalovirus IgG did not appear to increase gastroschisis risk. Primary EBV infection was not associated with gastroschisis, but observed associations with both IgM and IgG reactivities to EBV and HSV suggest that reactivations may be risk factors for it.

Decreasing prevalence and time trend of gastroschisis in 14 cities of Liaoning Province: 2006-2015

To identify trends in the prevalence of gastroschisis on the basis of a large population-based observation study with cases identified by the Liaoning Birth Defects Registry including 14 cities over the course of a 10-year period. Data were obtained from the aforementioned registry which was maintained by the Liaoning Women and Children's Health Hospital, a comprehensive care institution as well as being responsible for the women's and children's health care guidance in this province. Gastroschisis prevalence, percent change, annual percent change (APC), and contribution rates of each city were calculated. We observed 747 cases of gastroschisis among 3,248,954 live births, for a prevalence of 2.30 per 10,000 births. The gastroschisis prevalence significantly decreased by 12.63% per year in Liaoning Province. Although the decreasing trends were observed in all these 14 cities, significant results were only observed in Shenyang (APC = -16.31%), Tieling (APC = -20.23%), and Chaoyang (APC = -13.50%). Notably, Tieling, Shenyang, and Yingkou were the three major cities which contributed almost 37.17% of the decreasing trend of gastroschisis in Liaoning Province. In conclusion, our findings demonstrate that the prevalence of gastroschisis has been decreasing during the recent decade among 14 cities in Liaoning Province.

Gene variants as risk factors for gastroschisis

In a population‐based case‐control study in California of 228 infants, we investigated 75 genetic variants in 20 genes and risk of gastroschisis with regard to maternal age, race/ethnicity, vitamin use, and smoking exposure. We hypothesized that genes related to vascular compromise may interact with environmental factors to affect the risk of gastroschisis. Haplotypes were constructed for 75 gene variants using the HaploView program. Risk for gastroschisis associated with each gene variant was calculated for both the homozygotes and the heterozygotes, with the homozygous wildtypes as the referent. Risks were estimated as odds ratios (ORs) with 95% confidence intervals (CIs) by logistic regression. We found 11 gene variants with increased risk and four variants with decreased risk of gastroschisis for heterozygous (OR_h) or homozygous variants (OR_v) genotypes. These included NOS3 (rs1036145) OR_h = 0.4 (95% CI: 0.2–0.7); NOS3 (rs10277237) OR_v = 2.7 (95% CI: 1.3–6.0); ADD1 (rs12503220) OR_h = 2.9 (95% CI: 1.6–5.4), GNB3 (rs5443) OR_h = 0.2 (95% CI: 0.1–0.5), OR_v = 0.4 (95% CI: 0.2–0.9); ICAM1 (rs281428) OR_v = 6.9 (95% CI: 2.1–22.9), ICAM1 (rs3093030) OR_v = 2.6 (95% CI: 1.2–5.6); ICAM4 (rs281438) OR_v = 4.9 (95% CI: 1.4–16.6), ICAM5 (rs281417) OR_h = 2.1 (95% CI: 1.1–4.1), OR_v = 4.8 (95% CI: 1.7–13.6); ICAM5 (rs281440) OR_h = 23.7 (95% CI: 5.5–102.5), OR_v = 20.6 (95% CI: 3.4–124.3); ICAM5 (rs2075741) OR_v = 2.2 (95% CI: 1.1–4.4); NAT1 OR_v = 0.3 (95% CI: 0.1–0.9). There were additional associations between several gene variants and gastroschisis among women aged 20–24 and among mothers with and without vitamin use. NOS3, ADD1, ICAM1, ICAM4, and ICAM5 warrant further investigation in additional populations and with the interaction of additional environmental exposures. © 2016 Wiley Periodicals, Inc.

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.

Geographic clusters of congenital anomalies in Argentina

Geographical clusters are defined as the occurrence of an unusual number of cases higher than expected in a given geographical area in a certain period of time. The aim of this study was to identify potential geographical clusters of specific selected congenital anomalies (CA) in Argentina. The cases were ascertained from 703,325 births, examined in 133 maternity hospitals in the 24 provinces of Argentina. We used the spatial scan statistic to determine areas of Argentina which had statistically significant elevations of prevalence. Prenatal diagnosis followed by referral of high-risk pregnancies to high complexity hospitals in a hospital-based surveillance system can create artifactual clusters. We assessed the referral bias by evaluating the prevalence heterogeneity within each cluster. Eight clusters of selected CAs with unusually high birth prevalence were identified: anencephaly, encephalocele, spina bifida, diaphragmatic hernia, talipes equinovarus, omphalocele, Cleft lip with or without cleft palate (CL/P), and Down syndrome. The clusters of Down syndrome and CL/P observed in this study match the previously reported clusters. These findings support local targeted interventions to lower the prevalence of the CAs and/or further research on the cause of each cluster. The clusters of spina bifida, anencephaly, encephalocele, omphalocele, congenital diaphragmatic hernia, and talipes equinovarus may be influenced by prenatal diagnosis and referral to high complexity hospitals.

Spatial variability of gastroschisis in Canada, 2006-2011: An exploratory analysis

OBJECTIVES

Gastroschisis is a serious birth defect of the abdominal wall that is associated with mortality and significant morbidity. Our understanding of the factors causing this defect is limited. The objective of this paper is to describe the geographic variation in incidence of gastroschisis and characterize the spatial pattern of all gastroschisis cases in Canada between 2006 and 2011. Specifically, we aimed to ascertain the differences in spatial patterns between geographic regions and identify significant clusters and their location.

METHODS

The study population included 641 gastroschisis cases from the Canadian Pediatric Surgery Network (CAPSNet) database, a population-based dataset of all gastroschisis cases in Canada. Cases were geocoded based on maternal residence. Using Statistics Canada live-birth data as a denominator, the total prevalence of gastroschisis was calculated at the provincial/territorial levels. Random effects logistic models were used to estimate the rates of gastroschisis in each census division. These rates were then mapped using ArcGIS. Cluster detection was performed using Local Indicators of Spatial Association (LISA).

RESULTS

There is significant spatial heterogeneity of the rate of gastroschisis across Canada at both the provincial/territorial and census-division level. The Yukon, Northwest Territories and Prince Edward Island have higher overall rates of gastroschisis relative to other provinces/territories. Several census divisions in Alberta, Manitoba, Saskatchewan, Ontario, Northwest Territories and British Columbia demonstrated case "clusters", i.e., focally higher rates in discrete areas relative to surrounding areas.

CONCLUSIONS

There is clear evidence of spatial variation in the rates of gastroschisis across Canada. Future research should explore the role of area-based variables in these patterns to improve our understanding of the etiology of gastroschisis.

[Recurrence of pregnancies with gastroschisis: a case report]

Gastroschisis, a parietal anomaly belonging to median celosomia, is characterized by right lateral-umbilical evisceration. Its frequency, estimated at 1 birth in 2700, shows an excellent final prognosis conditioned by the digestive ischemic damage found at birth whose therapeutic management is often limited. No genetic cause is currently incriminated in the genesis of gastroschisis, except syndromic group associations. In this original observation, we report the case of a couple with a normal history whose obstetric management of the first pregnancy showed a fetus with gastroschisis at 12 WG, with primary closure at birth. The same couple began a second pregnancy in post-partum with on the first-quarter echography showing gastroschisis. A boy was delivered vaginally with extraction, who died of a multivisceral failure at 48h of life. Although no genetic factor is currently identified in gastroschisis onset and although only environmental factors such as illicit substance consumption, young maternal age, and socio-economic precariousness explain the genesis of this parietal anomaly, our observation is original because of the recurrence of this anomaly in the same woman during two successive pregnancies. The early characteristic of the second pregnancy, starting as soon as menstruation returned, can explain the organogenesis of this second gestation in a similar environmental context.

Prevalence and risk factors for gastroschisis in a public hospital from west México

Mexico is recognized as a country with a high prevalence of gastroschisis, although the cause of this remains unclear. We define the prevalence and potential risk factors for gastroschisis in a public hospital from west México. A case-control study was conducted among 270 newborns, including 90 patients with nonsyndromic gastroschisis (cases) and 180 infants without birth defects (controls), born all during the period 2009 to 2013 at the Hospital Civil de Guadalajara "Dr. Juan I. Menchaca" (Guadalajara, Mexico), from a total of 51,145 live births. Potential maternal risk factors for gastroschisis were compared using multivariate logistic regression analysis to evaluate the deviance explained by different variables of interest. The overall prevalence of gastroschisis in live births was 17.6 per 10,000 births (95% confidence interval [CI] 14.0-21.2), whereas in offspring of women ≤ 19 years old was 29.9 per 10,000 births (95% CI 21.9-38.0). Mothers ≤ 19 years (adjusted odds ratio [aOR] 2.8: 95% CI 1.5-5.1), anemia during pregnancy (aOR 10.7; 95% CI 2.0-56.9), first-trimester exposure to hormonal contraceptives (aOR 3.7; 95% CI 1.0-13.0), and first-trimester alcohol consumption (aOR 3.4; 95% CI 1.6-7.3), were associated with gastroschisis. Contrarily, adjusted OR for pre-pregnancy body mass index ≥ 25 kg/m(2) has protective odds (aOR 0.2; 95% CI 0.1-0.5). Our results suggest an increased risk for gastroschisis among mothers under the age of 20, with anemia during pregnancy, and those who used hormonal contraceptives or consumed alcohol during early pregnancy, whereas, pre-pregnancy overweight has a protective OR, and they are discussed as clues in its pathogenesis.

Spatial analysis of gastroschisis in Massachusetts and Texas

PURPOSE

Previous research has suggested gastroschisis, a congenital malformation, may be linked to environmental or infectious factors and cases can occur in clusters. The objective of this study was to identify geographic areas of elevated gastroschisis risk.

METHODS

Cases of gastroschisis were identified from birth defect registries in Massachusetts and Texas. Random samples of live births were selected as controls. Generalized additive models were used to create a continuous map surface of odds ratios (ORs) by smoothing over latitude and longitude. Maternal age, race/ethnicity, education, cigarette smoking, and insurance status (MA only) were assessed for confounding. We used permutation tests to identify statistically significant areas of increased risk.

RESULTS

An area of increased risk was identified in North Central Massachusetts but was not significant after adjustment (P value = .07; OR = 2.0). In Texas, two statistically significant areas of increased risk were identified after adjustment (P value = .02; OR = 1.3 and 1.2). Texas had sufficient data to assess the combination of space and time, which identified an increased risk in 2003 and 2004.

CONCLUSIONS

This study suggests there were areas of elevated gastroschisis risk in Massachusetts and Texas, which cannot be explained by the risk factors we assessed. Additional exploration of underlying artifactual, environmental, infectious, or behavioral factors may further our understanding of gastroschisis.

Maternal genitourinary infections and the risk of gastroschisis

Genitourinary infections (GUIs) have been associated with increased risk of gastroschisis in 2 studies. Using data collected in the Slone Epidemiology Center Birth Defects Study, we examined the association between GUI and gastroschisis. From 1998 to 2010, mothers of 249 gastroschisis cases and 7,104 controls were interviewed within 6 months of delivery about pregnancy events, including vaginal infections, genital herpes, urinary tract infections (UTIs), and other sexually transmitted diseases (STDs). Women were considered exposed if they reported at least 1 instance of a GUI in the first trimester. Logistic regression models were used to calculate odds ratios and 95% confidence intervals. Women who reported having any GUI had an adjusted odds ratio of 1.8 (95% confidence interval (CI): 1.3, 2.4). The highest risk was seen among women who reported a UTI only (adjusted odds ratio = 2.3, 95% CI: 1.5, 3.5), while the odds ratio for an STD only was slightly elevated (adjusted odds ratio = 1.2, 95% CI: 1.0, 1.5). Among women under 25 years of age, the odds ratio for UTI only was 2.6 (95% CI: 1.7, 4.0), and among older women it was 1.8 (95% CI: 0.6, 5.9). When we considered the joint association of UTIs and young maternal age, a synergistic effect was observed. The results of this study add further evidence that UTIs may increase the risk of gastroschisis.

Early pregnancy agricultural pesticide exposures and risk of gastroschisis among offspring in the San Joaquin Valley of California

BACKGROUND

Prevalence of gastroschisis has inexplicably been increasing over the past few decades. Our intent was to explore whether early gestational exposures to pesticides were associated with risk of gastroschisis.

METHODS

We used population-based data, accompanied by detailed information from maternal interviews as well as information on residential proximity to a large number of commercial pesticide applications during early pregnancy. The study population derived from the San Joaquin Valley of California (). Cases were 156 infants/fetuses with gastroschisis and controls were 785 infants without birth defects.

RESULTS

Among 22 chemical pesticide groups analyzed, none had an elevated odds ratio with an associated confidence interval that excluded 1.0, although exposure to the triazine group showed borderline significance. Among 36 specific pesticide chemicals analyzed, only exposure to petroleum distillates was associated with an elevated risk, odds ratio = 2.5 (1.1-5.6). In general, a substantially different inference was not derived when analyses were stratified by maternal age or when risk estimation included adjustment for race/ethnicity, body mass index, folic acid supplement use, and smoking.

CONCLUSION

Our study rigorously adds to the scant literature on this topic. Our a priori expectation was that we would observe certain pesticide compounds to be particularly associated with young age owing to the disproportionate risk observed for young women to have offspring with gastroschisis. We did not observe an exposure profile unique to young women.

Maternal smoking, xenobiotic metabolizing enzyme gene variants, and gastroschisis risk

Maternal smoking during pregnancy is one proposed risk factor for gastroschisis, but reported associations have been modest, suggesting that differences in genetic susceptibility might play a role. We included 108 non-Hispanic white and 62 Hispanic families who had infants with gastroschisis, and 1,147 non-Hispanic white and 337 Hispanic families who had liveborn infants with no major structural birth defects (controls) in these analyses. DNA was extracted from buccal cells collected from infants and mothers, and information on periconceptional smoking history was obtained from maternal interviews, as part of the National Birth Defects Prevention Study. We analyzed five polymorphisms in three genes that code for enzymes involved in metabolism of some cigarette smoke constituents (CYP1A1, CYP1A2, and NAT2). Logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) independently for maternal smoking and maternal and infant gene variants, and to assess joint associations of maternal smoking and maternal or infant gene variants with gastroschisis. In analyses adjusted for maternal age at delivery and stratified by maternal race-ethnicity, we identified three suggestive associations among 30 potential associations with sufficient numbers to calculate ORs: CYP1A1*2A for non-Hispanic white mothers who smoked periconceptionally (aOR = 0.38, 95% CI 0.15-0.98), and NAT2*6 for Hispanic non-smoking mothers (aOR = 2.17, 95% CI 1.12-4.19) and their infants (aOR = 2.11, 95% CI 1.00-4.48). This analysis does not support the occurrence of effect modification between periconceptional maternal smoking and most of the xenobiotic metabolizing enzyme gene variants assessed.

Gastroschisis--what should be told to parents?

Gastroschisis is a common congenital abdominal wall defect. It is almost always diagnosed prenatally thanks to routine maternal serum screening and ultrasound screening programs. In the majority of cases, the condition is isolated (i.e. not associated with chromosomal or other anatomical anomalies). Prenatal diagnosis allows for planning the timing, mode and location of delivery. Controversies persist concerning the optimal antenatal monitoring strategy. Compelling evidence supports elective delivery at 37  weeks' gestation in a tertiary pediatric center. Cesarean section should be reserved for routine obstetrical indications. Prognosis of infants with gastroschisis is primarily determined by the degree of bowel injury, which is difficult to assess antenatally. Prenatal counseling usually addresses gastroschisis issues. However, parental concerns are mainly focused on long-term postnatal outcomes including gastrointestinal function and neurodevelopment. Although infants born with gastroschisis often endure a difficult neonatal course, they experience few long-term complications. This manuscript, which is structured around common parental questions and concerns, reviews the evidence pertaining to the antenatal, neonatal and long-term implications of a fetal gastroschisis diagnosis and is aimed at helping healthcare professionals counsel expecting parents.

The role of maternal stress in early pregnancy in the aetiology of gastroschisis: an incident case control study

Objective

The incidence of gastroschisis, a congenital anomaly where the infant abdominal wall is defective and intestines protrude from the abdominal cavity, is increasing in many countries. The role of maternal stress in some adverse birth outcomes is now well established. We tested the hypothesis that major stressful life events in the first trimester are risk factors for gastroschisis, and social support protective, in a case-control study in the United Kingdom.

Methods

Gastroschisis cases and three controls per case (matched for maternal age) were identified at routine 18-20 week fetal anomaly ultrasound scan, in 2007-2010. Face to face questionnaire interviews were carried out during the antenatal period (median 24 weeks gestation) asking about serious stressful events and social support in the first trimester. Data were analysed using conditional logistic regression.

Results

Two or more stressful life events in the first trimester (adjusted OR 4.9; 95% CI 1.2-19.4), and moving address in the first trimester (aOR 4.9; 95% CI 1.7-13.9) were strongly associated with risk of gastroschisis, independent of behavioural risk factors including smoking, alcohol, and poor diet. Perceived availability of social support was not associated with reduced risk of gastroschisis (aOR 0.8; 95% CI 0.2-3.1).

Conclusions

Stressful maternal life events in the first trimester of pregnancy including change of address were strongly associated with a substantial increase in the risk of gastroschisis, independent of stress related high risk behaviours such as smoking, alcohol consumption and poor diet. This suggests that stress pathways are involved in the aetiology of gastroschisis.

Violence against women and gastroschisis: a case-control study

BACKGROUND

Gastroschisis, a birth defect characterized by herniated fetal abdominal wall, occurs more commonly in infants born to teenage and young mothers. Ischemia of the vascular vitelline vessels is the likely mechanism of pathogenesis. Given that chronic stress and violence against women are risk factors for cardiovascular disease we explored whether these may represent risk factors for gastroschisis, when they occur during pregnancy. A case-control study was conducted, with 15 incident cases of children born with gastroschisis in the Region of Murcia, Spain, from December 2007 to June 2013. Forty concurrent controls were recruited at gestation weeks 20-24 or post-partum. All mothers of cases and controls completed a comprehensive, in-person, 'green sheet' questionnaire on environmental exposures.

RESULTS

Mothers of children with gastroschisis were younger, smoked more cigarettes per week relative to controls, were exposed to higher amounts of illegal drugs, and suffered from domestic violence more frequently than the controls. Multivariable logistic regression analysis highlights periconceptional 'gender-related violence' (OR: 16.6, 95% CI 2.7 to 101.7) and younger maternal age (OR 1.1, 95% CI 1.0-1.3).

CONCLUSIONS

Violence against pregnant women is associated with birth defects, and should be studied in more depth as a cause-effect teratogenic. Psychosocial risk factors, including gender-based violence, are important for insuring the health and safety of the pregnant mother and the fetus.

Antiherpetic medication use and the risk of gastroschisis: findings from the National Birth Defects Prevention Study, 1997-2007

BACKGROUND

Previous studies examining the teratogenic effects of antiherpetic medications have found no associations for birth defects overall but have not examined the risk of specific birth defects.

METHODS

The National Birth Defects Prevention Study ascertains population-based cases with birth defects and live-born controls without birth defects in 10 states across the United States for the purpose of identifying potential teratogenic risk factors. Mothers of cases and controls are interviewed within 2 years of their estimated date of delivery about demographic, medical and behavioural factors before and during pregnancy. This analysis examined the possible association between use of antiherpetic medications (acyclovir, valacyclovir or famciclovir) during early pregnancy and gastroschisis, a birth defect of the abdominal wall.

RESULTS

The mothers of 1.1% (n = 10) of 941 gastroschisis cases and 0.3% (n = 27) of 8339 controls reported antiherpetic medication use during the month before conception through the third month of pregnancy. The adjusted odds ratios for such use in relation to gastroschisis were 4.7 [95% confidence interval 1.7, 13.3] and 4.7 [95% CI 1.2, 19.0] among women with and without self-reported genital herpes, respectively, when compared with women without antiherpetic use or herpes. Among women reporting no antiherpetic medication use, the odds ratio for self-reported genital herpes in relation to gastroschisis was 3.0 [95% CI 1.6, 5.7].

CONCLUSIONS

Our study raises the possibility of an increased risk of gastroschisis because of either antiherpetic medication use during early pregnancy or the underlying genital herpes infection for which it was indicated.

The association of ambient air pollution and traffic exposures with selected congenital anomalies in the San Joaquin Valley of California

Congenital anomalies are a leading cause of infant mortality and are important contributors to subsequent morbidity. Studies suggest associations between environmental contaminants and some anomalies, although evidence is limited. We aimed to investigate whether ambient air pollutant and traffic exposures in early gestation contribute to the risk of selected congenital anomalies in the San Joaquin Valley of California, 1997-2006. Seven exposures and 5 outcomes were included for a total of 35 investigated associations. We observed increased odds of neural tube defects when comparing the highest with the lowest quartile of exposure for several pollutants after adjusting for maternal race/ethnicity, education, and multivitamin use. The adjusted odds ratio for neural tube defects among those with the highest carbon monoxide exposure was 1.9 (95% confidence interval: 1.1, 3.2) compared with those with the lowest exposure, and there was a monotonic exposure-response across quartiles. The highest quartile of nitrogen oxide exposure was associated with neural tube defects (adjusted odds ratio = 1.8, 95% confidence interval: 1.1, 2.8). The adjusted odds ratio for the highest quartile of nitrogen dioxide exposure was 1.7 (95% confidence interval: 1.1, 2.7). Ozone was associated with decreased odds of neural tube defects. Our results extend the limited body of evidence regarding air pollution exposure and adverse birth outcomes.

Association between maternal age and birth defects of unknown etiology: United States, 1997-2007

BACKGROUND

Birth defects affect 3% of babies born, and are one of the leading causes of infant mortality. Both younger and older maternal age may pose increased risks for certain birth defects. This study assessed the relationship between maternal age at the estimated delivery date and the risk for birth defects.

METHODS

Data were obtained from the National Birth Defects Prevention Study, a population-based case-control study including mothers across 10 states. Maternal age was stratified into six categories: <20, 20 to 24, 25 to 29, 30 to 34, 35 to 39, and ≥40 years, and also analyzed as a continuous variable. Logistic regression models adjusted formaternal race/ethnicity, education, body mass index (BMI), folic acid use, smoking, gravidity, and parental age difference were used to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CIs).

RESULTS

For maternal age <20 years, associations with total anomalous pulmonary venous return (aOR, 2.3; 95% CI, 1.3-4.0), amniotic band sequence (aOR, 2.4; 95% CI, 1.5-3.8), and gastroschisis (aOR, 6.1; 95% CI, 4.8-8.0) were observed. For the ≥40 year age group, associations with several cardiac defects, esophageal atresia (aOR, 2.9; 95% CI, 1.7-4.9), hypospadias (aOR, 2.0; 95% CI, 1.4-3.0), and craniosynostosis (aOR, 1.6; 95% CI, 1.1-2.4) were observed. Results using maternal age as a continuous variable were consistent with those that used categorized maternal age.

CONCLUSION

Elucidating risk factors specific to women ateither extreme of maternal age may offer prevention opportunities. All women should be made aware of prevention opportunities, such as folic acid supplementation, to reduce the occurrence of birth defects.

Short interpregnancy interval and gastroschisis risk in the National Birth Defects Prevention Study

BACKGROUND

The micronutrient depletion hypothesis proposes that consecutive pregnancies spaced too closely may leave insufficient time for maternal micronutrient replenishment. Short interpregnancy intervals (IPI) have been associated with an increased risk for several adverse pregnancy outcomes, but an association with gastroschisis risk has not been previously explored.

METHODS

Within a population-based, case-control study, we evaluated the association between IPI length and gastroschisis risk using multivariable logistic regression models to estimate gastroschisis odds ratios for IPI <12 months and 12 to 17 months relative to those 18 to 23 months. We further evaluated the association between IPI and gastroschisis risk stratified by maternal age, periconceptional multivitamin use, preceding pregnancy outcome, study center region, and season of conception to explore whether observed associations were compatible with the hypothesis of maternal micronutrient depletion.

RESULTS

For women with IPI <12 months, the adjusted odds ratio (aOR) was 1.7 (95% confidence interval [CI]: 1.1-2.5). The magnitude of the observed effect did not differ among strata of maternal age or periconceptional multivitamin use. However, the association was more pronounced after a miscarriage or termination (aOR: 2.5; 95% CI: 1.1-5.6) and among women who resided in northern study areas (aOR: 2.8; 95% CI: 1.3-5.9). The higher risk observed with short IPI among women in northern study areas was attenuated for spring/summer conceptions.

CONCLUSION

Short IPI was associated with an increased risk for gastroschisis, particularly among women whose preceding pregnancy resulted in a miscarriage or termination and among those who resided in northern study areas with winter/fall conception.

The role of maternal nutrition in the aetiology of gastroschisis: an incident case-control study

BACKGROUND

Gastroschisis, a congenital anomaly involving a defect in the fetal abdominal wall, has increased in prevalence in many countries, but the aetiology is uncertain. We tested the hypothesis that high maternal alcohol consumption and poor diet in the first trimester are risk factors in a case-control study in the UK (1 July 2007 to 28 February 2010).

METHODS

Gastroschisis cases and three controls per case (matched for maternal age) were identified at 18- to 20-week routine anomaly screening ultrasound scan (USS). Interviews were carried out during the antenatal period (median 24 weeks' gestation) using a piloted questionnaire. Conditional logistic regression was used to describe the associations between exposure variables and gastroschisis, adjusted for known confounding variables.

RESULTS

The response rate was 73% for cases (n = 91) and 70% for controls (n = 217). High consumption of fruits and vegetables during the first trimester (aOR 0.2; 95% CI 0.04-0.6), taking folic acid for at least 6 weeks during the first trimester (aOR 0.3; 95% CI 0.1-0.7) and increasing body fat percentage of total maternal body weight (aOR 0.9; 95% CI 0.8-0.9 per 1% increase) were independently associated with reduced risk. Cigarette smoking (aOR 2.7; 95% CI 1.1-6.8) was an independent risk factor.

CONCLUSION

We report for the first time that higher intake of fruits and vegetables during the first trimester, longer duration of folic acid supplementation and higher body fat percentage are associated with reduced risk of fetal gastroschisis, independent of cigarette smoking. The increased risk of cigarette smoking is greatest in older women and in high socio-economic groups.