The prevalence of congenital anomalies in Europe

EUROCAT (European Surveillance of Congenital Anomalies) is the network of population-based registers of congenital anomaly in Europe, with a common protocol and data quality review, covering 1.5 million annual births in 22 countries. EUROCAT recorded a total prevalence of major congenital anomalies of 23.9 per 1,000 births for 2003-2007. 80% were livebirths. 2.5% of livebirths with congenital anomaly died in the first week of life. 2.0% were stillbirths or fetal deaths from 20 weeks gestation. 17.6% of all cases were terminations of pregnancy following prenatal diagnosis (TOPFA). Thus, congenital anomalies overwhelmingly concern children surviving the early neonatal period, who have important medical, social or educational needs. The prevalence of chromosomal anomalies was 3.6 per 1,000 births, contributing 28% of stillbirths/fetal deaths from 20 weeks gestation with congenital anomaly, and 48% of all TOPFA. Congenital heart defects (CHD) were the most common non-chromosomal subgroup, at 6.5 per 1,000 births, followed by limb defects (3.8 per 1,000), anomalies of urinary system (3.1 per 1,000) and nervous system defects (2.3 per 1,000). In 2004, perinatal mortality associated with congenital anomaly was 0.93 per 1,000 births, and TOPFA 4.4 per 1,000 births, with considerable country variation. Primary prevention of congenital anomalies in the population based on controlling environmental risk factors is a crucial policy priority, including preconceptional care and whole population approaches.

Use of selective serotonin-reuptake inhibitors in pregnancy and the risk of birth defects

BACKGROUND

Information regarding the safety of selective serotonin-reuptake inhibitors (SSRIs) in human pregnancy is sparse. Concern has been raised about the risk of congenital heart defects associated with the use of SSRIs in pregnancy.

METHODS

We obtained data on 9622 case infants with major birth defects and 4092 control infants born from 1997 through 2002 from the National Birth Defects Prevention Study. Case infants were ascertained through birth-defects surveillance systems in eight U.S. states; controls were selected randomly from the same geographic areas. Mothers completed a standardized telephone interview regarding exposure to potential risk factors, including medications, before and during pregnancy. Exposure to SSRIs was defined as treatment with any SSRI from 1 month before to 3 months after conception. Birth defects were assigned to 26 categories and subcategories.

RESULTS

There were no significant associations between maternal use of SSRIs overall during early pregnancy and congenital heart defects or most other categories or subcategories of birth defects. Maternal SSRI use was associated with anencephaly (214 infants, 9 exposed; adjusted odds ratio, 2.4; 95% confidence interval [CI], 1.1 to 5.1), craniosynostosis (432 infants, 24 exposed; adjusted odds ratio, 2.5; 95% CI, 1.5 to 4.0), and omphalocele (181 infants, 11 exposed; adjusted odds ratio, 2.8; 95% CI, 1.3 to 5.7).

CONCLUSIONS

Maternal use of SSRIs during early pregnancy was not associated with significantly increased risks of congenital heart defects or of most other categories of birth defects. Associations were observed between SSRI use and three types of birth defects, but the absolute risks were small, and these observations require confirmation by other studies.

Maternal medication use and risks of gastroschisis and small intestinal atresia

Gastroschisis and small intestinal atresia (SIA) are birth defects that are thought to arise from vascular disruption of fetal mesenteric vessels. Previous studies of gastroschisis have suggested that risk is increased for maternal use of vasoactive over-the-counter medications, including specific analgesics and decongestants. This retrospective study evaluated the relation between maternal use of cough/cold/analgesic medications and risks of gastroschisis and SIA. From 1995 to 1999, the mothers of 206 gastroschisis cases, 126 SIA cases, and 798 controls in the United States and Canada were interviewed about medication use and illnesses. Risks of gastroschisis were elevated for use of aspirin (odds ratio = 2.7, 95% confidence interval: 1.2, 5.9), pseudoephedrine (odds ratio = 1.8, 95% confidence interval: 1.0, 3.2), acetaminophen (odds ratio = 1.5, 95% confidence interval: 1.1, 2.2), and pseudoephedrine combined with acetaminophen (odds ratio = 4.2, 95% confidence interval: 1.9, 9.2). Risks of SIA were increased for any use of pseudoephedrine (odds ratio = 2.0, 95% confidence interval: 1.0, 4.0) and for use of pseudoephedrine in combination with acetaminophen (odds ratio = 3.0, 95% confidence interval: 1.1, 8.0). Reported fever, upper respiratory infection, and allergy were not associated with risks of either defect. These findings add more evidence that aspirin use in early pregnancy increases risk of gastroschisis. Although pseudoephedrine has previously been shown to increase gastroschisis risk, findings of this study raise questions about interactions between medications and possible confounding by underlying illness.

Aspirin consumption during the first trimester of pregnancy and congenital anomalies: a meta-analysis

OBJECTIVE

The purpose of this study was to determine, on the basis of published reports, whether aspirin use during the first trimester of pregnancy is associated with an increased risk of congenital malformations.

STUDY DESIGN

We reviewed the literature for published studies that reported exposure to aspirin during the first trimester of pregnancy and congenital malformations. Two reviewers independently determined whether a study should be included in the final analysis and extracted the data. We calculated the pooled odds ratio and 95% CI.

RESULTS

Twenty-two studies met the inclusion criteria. In the eight studies that reported an overall risk, the risk of congenital malformations in offspring of women who were exposed to aspirin was not significantly higher than that in control subjects (odds ratio, 1.33; 95% CI, 0.94-1.89). However, a significantly increased risk of gastroschisis (odds ratio, 2.37; 95% CI, 1.44-3.88) was found.

CONCLUSION

We found no evidence of an overall increase in the risk of congenital malformations that could be associated with aspirin. Aspirin exposure during the first trimester may be associated with an increased risk of gastroschisis.

Increasing prevalence of gastroschisis in Europe 1980-2002: a phenomenon restricted to younger mothers?

Gastroschisis is an abdominal wall defect more prevalent in offspring of young mothers. It is known to be increasing in prevalence despite the general decrease in the proportion of births to young European women. We investigated whether the increase in prevalence was restricted to the high-risk younger mothers. We analysed 936 cases of gastroschisis from 25 population-based registries in 15 European countries, 1980-2002. We fitted a Bayesian Hierarchical Model which allowed us to estimate trend, to estimate which registries were significantly different from the common distribution, and to adjust simultaneously for maternal age, time (in grouped years) and the random variation between registries. The maternal age-standardised prevalence (standardised to the year 2000 European maternal age structure) increased almost fourfold from 0.54 [95% Credible Interval (CrI) 0.37, 0.75] per 10,000 births in 1980-84 to 2.12 [95% CrI 1.85, 2.40] per 10,000 births in 2000-02. The relative risk of gastroschisis for mothers <20 years of age in 1995-2002 was 7.0 [95% CrI 5.6, 8.7]. There were geographical differences within Europe, with higher rates of gastroschisis in the UK, and lower rates in Italy after adjusting for maternal age. After standardising for regional variation, our results showed that the increase in risk over time was the same for mothers of all ages--the increase for mothers <20 years was 3.96-fold compared with an increase of 3.95-fold for mothers in the other age groups. These findings indicate that the phenomenon of increasing gastroschisis prevalence is not restricted to younger mothers only.

Development of gastroschisis: review of hypotheses, a novel hypothesis, and implications for research

Gastroschisis, a ventral body wall defect, is a continuing challenge and concern to researchers, clinicians, and epidemiologists seeking to identify its cause(s) and pathogenesis. Concern has been renewed in recent years because, unlike most other birth defects, rates of gastroschisis are reportedly increasing in many developed and developing countries. No tenable explanation or specific causes have been identified for this trend. Rates of gastroschisis are particularly high among pregnancies of very young women. Such an intriguing association, not observed to this degree with other birth defects, may afford clues to the defect's cause. Understanding the causes of gastroschisis may provide insight to the defect's origin. In pursuing such causal studies, it would be helpful to understand the embryogenesis of gastroschisis. To date, four main embryologic hypotheses have been proposed: (1) Failure of mesoderm to form in the body wall; (2) Rupture of the amnion around the umbilical ring with subsequent herniation of bowel; (3) Abnormal involution of the right umbilical vein leading to weakening of the body wall and gut herniation; and (4) Disruption of the right vitelline (yolk sac) artery with subsequent body wall damage and gut herniation. Although based on embryological phenomena, these hypotheses do not provide an adequate explanation for how gastroschisis would occur. Therefore, we propose an alternative hypothesis, based on well described embryonic events. Specifically, we propose that abnormal folding of the body wall results in a ventral body wall defect through which the gut herniates, leading to the clinical presentation of gastroschisis. This hypothesis potentially explains the origin of gastroschisis as well as that of other developmental defects of the ventral wall.

Congenital anterior abdominal wall defects in the north of England, 1986-1996: occurrence and outcome

The aim was to describe trends in prevalence, maternal age-specific prevalence, associated anomalies, clinical outcomes and the sensitivity of antenatal diagnosis of congenital anterior abdominal wall defects (in particular gastroschisis and exomphalos). Data were identified from a population-based register of major congenital abnormalities in the Northern health region of England, the Northern Congenital Abnormality Survey (NorCAS), between 1986 and 1996. 296 cases were notified; there were 133 cases of gastroschisis, 98 exomphalos, 30 limb-body wall defects and 23 other anterior abdominal wall defects. 12 cases could not be classified. In 19 (6 per cent) the initial diagnosis was changed following case review. 30 (30.6 per cent) cases of exomphalos were associated with a chromosomal anomaly compared with 1 (0.8 per cent) case of gastroschisis. The total prevalence for the 11 years was 6.33 (95 per cent CI=5.57-7.08) per 10 000 live births, still births and terminations of pregnancy, and the overall birth prevalence was 4.30 (95 per cent CI=3.68-4.93) per 10 000 live births and still births. For gastroschisis, there was a significant increase over the study period in both the total prevalence (1.48 in 1986 to 5.29 per 10 000 in 1996; chi(2)=8.41, p=0.00433) and the birth prevalence (1.48 in 1986 to 4.72 per 10 000 in 1996; chi(2)=7.42, p=0.00644), but there was no such significant increase for exomphalos (total prevalence chi(2)=2.29, p=0.13055; birth prevalence chi(2)=0.16, p=0.69348). The maternal age-specific prevalence was highest in the 11-19 year age group for gastroschisis but in the 35-39 year age group for exomphalos. Fewer pregnancies with gastroschisis resulted in a termination and a greater proportion of cases were alive at one year compared with exomphalos. The sensitivity of abnormality detection by ultrasonography was 75 per cent and 77.3 per cent for gastroschisis and exomphalos, respectively. Antenatal diagnosis improved from 47.4 per cent during 1986-91 to 80 per cent between 1992-96 for gastroschisis (chi(2)=5.7, p=0.00169), and from 55.6 per cent to 68.8 per cent for isolated exomphalos, although this increase was not significant. Total and birth prevalence of gastroschisis increased in the Northern region between 1986 and 1996. For exomphalos, there was a trend towards an increase in total prevalence and towards a decrease in birth prevalence. This decreasing trend has been accompanied by improvements in antenatal detection and subsequent termination of cases of exomphalos associated with other anomalies.

Evaluation of prenatal ultrasound diagnosis of fetal abdominal wall defects by 19 European registries

OBJECTIVES

To evaluate the current effectiveness of routine prenatal ultrasound screening in detecting gastroschisis and omphalocele in Europe.

DESIGN

Data were collected by 19 congenital malformation registries from 11 European countries. The registries used the same epidemiological methodology and registration system. The study period was 30 months (July 1st 1996-December 31st 1998) and the total number of monitored pregnancies was 690,123.

RESULTS

The sensitivity of antenatal ultrasound examination in detecting omphalocele was 75% (103/137). The mean gestational age at the first detection of an anomaly was 18 +/- 6.0 gestational weeks. The overall prenatal detection rate for gastroschisis was 83% (88/106) and the mean gestational age at diagnosis was 20 +/- 7.0 gestational weeks. Detection rates varied between registries from 25 to 100% for omphalocele and from 18 to 100% for gastroschisis. Of the 137 cases of omphalocele less than half of the cases were live births (n = 56; 41%). A high number of cases resulted in fetal deaths (n = 30; 22%) and termination of pregnancy (n = 51; 37%). Of the 106 cases of gastroschisis there were 62 (59%) live births, 13 (12%) ended with intrauterine fetal death and 31 (29%) had the pregnancies terminated.

CONCLUSIONS

There is significant regional variation in detection rates in Europe reflecting different policies, equipment and the operators' experience. A high proportion of abdominal wall defects is associated with concurrent malformations, syndromes or chromosomal abnormalities, stressing the need for the introduction of repeated detailed ultrasound examination as a standard procedure. There is still a relatively high rate of elective termination of pregnancies for both defects, even in isolated cases which generally have a good prognosis after surgical repair.

Gastroschisis and associated defects: An international study

Our objective was to evaluate the frequency and type of malformations associated with gastroschisis in a large pool of international data, to identify malformation patterns, and to evaluate the role of maternal age in non-isolated cases. Case-by-case information from 24 registries, all members of the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR), were evaluated. After the exclusion of other abdominal wall defects cases were classified as: (a) isolated; (b) recognizable syndrome, chromosomal or not; (c) multiple congenital anomalies (MCA). Our results showed that out of 3,322 total cases 469 non-isolated cases were registered (14.1%): 41 chromosomal syndromes, 24 other syndromes, and 404 MCA. Among MCA four groups of anomalies were most frequent: CNS (4.5%), cardio-vascular (2.5%), limb (2.2%), and kidney anomalies (1.9%). No similar patterns emerged except two patterns resembling limb-body wall complex and OEIS. In both of them the gastroschisis could be however misclassified. Chromosomal trisomies and possibly non-syndromic MCA are associated with an older maternal age more than isolated cases. On consideration of our data and the most valid studies published in the literature, the best estimate of the proportion of gastroschisis associated with major unrelated defects is about 10%, with a few cases associated to recognizable syndromes. Recognized syndromes with gastroschisis seem to be so exceptional that the well documented and validated cases are worth being published as interesting case report. An appropriate case definition in etiological studies should include only isolated gastroschisis after an appropriate definition of isolated and non-isolated cases and a thorough case-by-case review.

Specific birth defects in pregnancies of women with diabetes: National Birth Defects Prevention Study, 1997-2011

BACKGROUND

Diabetes is associated with an increased risk for many birth defects and is likely to have an increasing impact on birth defect prevalence because of the rise in diabetes in the United States in recent decades. One of the first analyses in which specific birth defects were assessed for their relationship with both pregestational and gestational diabetes used data from the initial 6 years of the National Birth Defects Prevention Study. That analysis reported strong associations for pregestational diabetes with several birth defects, but few exposures among some of the less common birth defects led to unstable estimates with wide confidence intervals. Since that analysis, the study continued to collect data for another 8 years, including information on approximately 19,000 additional cases and 6900 additional controls.

OBJECTIVE

Our objective was to use data from the National Birth Defects Prevention Study, the largest population-based birth defects case-control study in the United States, to provide updated and more precise estimates of the association between diabetes and birth defects, including some defects not previously assessed.

STUDY DESIGN

We analyzed data on deliveries from October 1997 through December 2011. Mothers of case and control infants were interviewed about their health conditions and exposures during pregnancy, including diagnosis of pregestational (type 1 or type 2) diabetes before the index pregnancy or gestational diabetes during the index pregnancy. Using logistic regression, we separately assessed the association between pregestational and gestational diabetes with specific categories of structural birth defects for which there were at least 3 exposed case infants. For birth defect categories for which there were at least 5 exposed case infants, we calculated odds ratios adjusted for maternal body mass index, age, education, race/ethnicity, and study site; for defect categories with 3 or 4 exposed cases, we calculated crude odds ratios.

RESULTS

Pregestational diabetes was reported by 0.6% of mothers of control infants (71 of 11,447) and 2.5% of mothers of case infants (775 of 31,007). Gestational diabetes during the index pregnancy was reported by 4.7% of mothers of control infants (536 of 11,447) and 5.3% of mothers of case infants (1,653 of 31,007). Pregestational diabetes was associated with strong, statistically significant odds ratios (range, 2.5-80.2) for 46 of 50 birth defects considered. The largest odds ratio was observed for sacral agenesis (adjusted odds ratio, 80.2; 95% confidence interval, 46.1-139.3). A greater than 10-fold increased risk was also observed for holoprosencephaly (adjusted odds ratio, 13.1; 95% confidence interval, 7.0-24.5), longitudinal limb deficiency (adjusted odds ratio, 10.1; 95% confidence interval, 6.2-16.5), heterotaxy (adjusted odds ratio, 12.3; 95% confidence interval, 7.3-20.5), truncus arteriosus (adjusted odds ratio, 14.9; 95% confidence interval, 7.6-29.3), atrioventricular septal defect (adjusted odds ratio, 10.5; 95% confidence interval, 6.2-17.9), and single ventricle complex (adjusted odds ratio, 14.7; 95% confidence interval, 8.9-24.3). For gestational diabetes, statistically significant odds ratios were fewer (12 of 56) and of smaller magnitude (range, 1.3- 2.1; 0.5 for gastroschisis).

CONCLUSION

Pregestational diabetes is associated with a markedly increased risk for many specific births defects. Because glycemic control before pregnancy is associated with a reduced risk for birth defects, ongoing quality care for persons with diabetes is an important opportunity for prevention.

Recreational drug use: a major risk factor for gastroschisis?

The authors tested the hypothesis that the birth prevalence of gastroschisis is positively associated with use of recreational drugs in early pregnancy. A matched case-control study was carried out in three regions of the United Kingdom over the period January 2001 through August 2003. For each case, three liveborn controls were matched by initial intended place of delivery, region, and maternal age. Maternal hair analysis provided independent verification of recreational drug use. Conditional logistic regression was used to estimate mutually adjusted odds ratios. Estimates were revised using data from hair analysis. Statistically significant adjusted odds ratios for gastroschisis were associated with first-trimester use of 1) any recreational drug (odds ratio (OR) = 2.2, 95% confidence interval (CI): 1.2, 4.3) and 2) vasoconstrictive recreational drugs (defined as cocaine, amphetamines, and ecstasy) (OR = 3.3, 95% CI: 1.0, 10.5). Other significant exposures included aspirin use (OR = 20.4, 95% CI: 2.2, 191.5), cigarette smoking (OR = 1.7, 95% CI: 1.1, 2.6), and prior history of gynecologic infection/disease (OR = 2.6, 95% CI: 1.2, 5.6). Recreational drug use is a significant risk factor for gastroschisis and is one of a constellation of potentially preventable exposures which include cigarette smoking, aspirin use, and history of gynecologic infection/disease. Maternal hair analysis proved an acceptable and valuable method of independently verifying recreational drug use.

Rising birth prevalence of gastroschisis

OBJECTIVE

Gastroschisis is a congenital anomaly that has been reported to be increasing in frequency. The objective of this study was to determine the birth prevalence of gastroschisis using two large databases.

STUDY DESIGN

We reviewed data from a statewide database and a national database from a neonatal health care provider, abstracting cases of gastroschisis.

RESULTS

In North Carolina, the birth prevalence of gastroschisis increased from 1.96 per 10,000 births in 1997 to 4.49 per 10,000 births in 2000 (p=0.0007). The overall increase was almost entirely because of the increase in infants born to mothers less than 20 years old. Among infants receiving care from the national neonatal provider, the prevalence of gastroschisis increased from 2.9 per 1000 patients in 1997 to five per 1000 patients in 2001 (p=0.044).

CONCLUSION

The birth prevalence of gastroschisis is increasing in North Carolina, and this trend may be occurring nationally. The rapid change in the birth prevalence in the subset of population most at risk for gastroschisis implicates environmental or pharmacologic teratogens rather than changing population characteristics as a causal factor in the development of gastroschisis.

Risk factors in congenital abdominal wall defects (omphalocele and gastroschisi): a study in a series of 265,858 consecutive births

The aim of this study was to describe the prevalence at birth of two abdominal wall defects (AWD), omphalocela and gastroschisis and to identify possible etiologic factors. The AWD came from 265,858 consecutive births of known ouome registered in the registry of congenital malformations of Strasbourg for the period 1979 to 1998. Request information on the child, the pregnancy, the parents and the family was obtained for cases and for controls. Hundred five cases with AWD were analysed, 55.2 % were omphalocele and 44.8 % were gastroschisis. The mean prevalence rate for omphalocele was 2.18 per 10,000 and for gastroschisis 1.76 per 10,000. Associated malformations were found in 74.1 % of omphalocele compared with 53.2 % of gastroschisis; 29.3 % of fetuses with omphalocele had an abnormal karyotype, 44,8 % had a recognizable syndrome, association or an unspecified malformation pattern; 51.0 % of fetuses with gastroschisis had additional malformations that were not of chromosomal origin, but 1 case. Antenatal ultrasound examination was able to detect 39 (67.2 %) cases of omphaloceles and 27 (57.4 %) cases of gastroschisis. In 30 (51.7 %) cases of omphalocele and in 7 (14.9 %) cases of gastroschisis parents opted for termination of pregnancy. The overall survival rate was 14 (24.1 %) for omphalocele and 30 (63.8 %) for gastroschisis. Weight, length and head circumference at birth of infants with AWD were less than those of controls. The weight of placenta of infants with AWD was not different from the weight of placenta of controls. Gastroschisis was associated with significantly younger maternal age than omphalocele. Pregnancies with AWD were more often complicated by threatened abortion, oligohydramnios and polyhydramnios. Mothers of children with AWD took more often medication during pregnancy than mothers of controls.

Gastroschisis: A sixteen-year review

PURPOSE

The aim of this study was to examine the incidence of gastroschisis in Saskatchewan over a 16-year period and identify risk factors associated with mortality.

METHODS

Information was obtained by retrospective review of all infant charts at the only 2 provincial neonatal intensive care centers from January 1985 through December 2000. Factors recorded were gestational age, birth weight, gender, Apgar score, time to operation, method of closure, time to attain full feedings, presence of sepsis, and length of hospital stay. Live birth data for the province was obtained, and the incidence per 10,000 live births for 3 time intervals was calculated. Analysis was performed with mortality as the dependent variable.

RESULTS

Seventy-one infants were identified. Overall survival rate was 93% (66 of 71). During the 3 time intervals examined, the incidence of gastroschisis per 10,000 live births increased from 1.85 in 1985 to 1990 to 3.66 in 1991 to 1995 to 4.06 in 1996 to 2000. The analysis found that intestinal atresia P =.009, OR = 18.3 (95%CI: 2.457-136) and intestinal necrosis P =.050, OR = 10.33 (95%CI: 1.32-80.68) were significantly associated with mortality.

CONCLUSIONS

The incidence of gastroschisis is increasing. Intestinal atresia and the development of intestinal necrosis were associated with poor outcome. Patients who had these complications all had short bowel, and full feedings could not be established. They required continuation of total parenteral nutrition and experienced episodes of sepsis.

Specific SSRIs and birth defects: Bayesian analysis to interpret new data in the context of previous reports

OBJECTIVE

To follow up on previously reported associations between periconceptional use of selective serotonin reuptake inhibitors (SSRIs) and specific birth defects using an expanded dataset from the National Birth Defects Prevention Study.

DESIGN

Bayesian analysis combining results from independent published analyses with data from a multicenter population based case-control study of birth defects.

SETTING

10 centers in the United States.

PARTICIPANTS

17,952 mothers of infants with birth defects and 9857 mothers of infants without birth defects, identified through birth certificates or birth hospitals, with estimated dates of delivery between 1997 and 2009.

EXPOSURES

Citalopram, escitalopram, fluoxetine, paroxetine, or sertraline use in the month before through the third month of pregnancy. Posterior odds ratio estimates were adjusted to account for maternal race/ethnicity, education, smoking, and prepregnancy obesity.

MAIN OUTCOME MEASURE

14 birth defects categories that had associations with SSRIs reported in the literature.

RESULTS

Sertraline was the most commonly reported SSRI, but none of the five previously reported birth defects associations with sertraline was confirmed. For nine previously reported associations between maternal SSRI use and birth defect in infants, findings were consistent with no association. High posterior odds ratios excluding the null value were observed for five birth defects with paroxetine (anencephaly 3.2, 95% credible interval 1.6 to 6.2; atrial septal defects 1.8, 1.1 to 3.0; right ventricular outflow tract obstruction defects 2.4, 1.4 to 3.9; gastroschisis 2.5, 1.2 to 4.8; and omphalocele 3.5, 1.3 to 8.0) and for two defects with fluoxetine (right ventricular outflow tract obstruction defects 2.0, 1.4 to 3.1 and craniosynostosis 1.9, 1.1 to 3.0).

CONCLUSIONS

These data provide reassuring evidence for some SSRIs but suggest that some birth defects occur 2-3.5 times more frequently among the infants of women treated with paroxetine or fluoxetine early in pregnancy.

Increasing risk of gastroschisis in Norway: an age-period-cohort analysis

The prevalence of gastroschisis in Norway, as reported to the Medical Birth Registry of Norway, increased regularly and sixfold from 0.5 to 2.9 per 10,000 births during 1967-1998. The prevalence was also consistently higher among children of younger mothers. The authors used age-period-cohort analysis to assess effects of both parents' age and year of birth (parental cohorts). Mother's and father's age were included in three different regression models. Apart from a significantly higher risk at a young maternal age, the authors also found higher risk at a young paternal age (1.6-fold per 10 years' reduction in father's age, 95% confidence interval: 1.0, 2.4). The time trend was highly significant regardless of whether it was ascribed to period, mother's year of birth, or father's year of birth. However, when father's year of birth was used to describe the time trend, no apparent additional effect of father's age was found, only for mother's age. The time trend is likely caused by environmental factors. Persistently increasing risks among children of young mothers may hypothetically be related to lifestyle factors. A contribution to risk also from fathers born in more recent years or from young fathers increases the likelihood that a factor related to modern lifestyles of young couples may be related to risk.

Increasing prevalence of gastroschisis: population-based study in California

OBJECTIVE

To evaluate time trend of gastroschisis and examine the epidemiological risk factors for gastroschisis.

STUDY DESIGN

This population-based study analyzed the active surveillance data from the California Birth Defects Monitoring Program from 1987 to 2003.

RESULTS

The overall birth prevalence of gastroschisis was 2.6 cases per 10,000 births (908 cases in >3.5 million births). In the adjusted analysis, by using the age of 25 to 29 years as the reference, mothers aged 12 to 15 years had a 4.2-times greater birth prevalence (95% CI, 2.5-7.0), and fathers aged 16 to 19 years and 20 to 24 years had 1.6- and 1.5-times greater birth prevalence (95% CI, 1.1-2.1 and 1.2-1.8), respectively. Compared with non-Hispanic whites and US-born Hispanic, both foreign-born Hispanics and blacks had adjusted prevalence ratio of 0.6 (95% CI, 0.5-0.7 and 0.4-0.9, respectively). In addition, nulliparity was also associated with gastroschisis. Independent of maternal age, paternal age, and maternal ethnicity, the birth prevalence increased 3.2-fold (95% CI, 2.3-4.3) during the 17-year study period.

CONCLUSIONS

The birth prevalence of gastroschisis continues to increase in California, and young, nulliparous women are at the greatest risk of having a child with gastroschisis.

Gastroschisis in the United States 1988-2003: analysis and risk categorization of 4344 patients

OBJECTIVE

Gastroschisis is a rare congenital abdominal wall defect through which intraabdominal organs herniate and it requires surgical management soon after birth. The objectives of this study were to profile patient characteristics of this anomaly utilizing data from two large national databases and to validate previous risk stratification categories of infants born with this condition.

METHODS

An analysis was performed using 13 years of the National Inpatient Sample database (1988-1996, 1998, 1999, 2001, 2002) and 3 years of the Kids' Inpatient Database (1997, 2000, 2003). These combined databases contain information from nearly 93 million discharges in the United States. Infants with gastroschisis were identified by International Classification of Disease-9 procedure code 54.71 (repair of gastroschisis) and an age at admission of <8 days. Variables of gender, race, geographic region, co-existing diagnoses, length of stay, hospital charges adjusted to 2005 dollars, complications and inpatient mortality were collected from the databases. Infants were divided into simple and complex categories based on the absence or presence of intestinal atresia, stenosis, perforation, necrosis or volvulus. Comparisons between groups were performed using Pearson's chi (2) for categorical outcomes and the Kruskal-Wallis test for non-normally distributed continuous variables.

RESULTS

A total of 4344 infants with gastroschisis were identified. These were comprised of 44.0% female infants (n=1910), 46.4% male infants (n=2017) whereas 9.6% were not reported (n=415). Racial analysis showed the largest subset being white in 40.9% of infants (n=1775) with Hispanic infants being the next highest group reported at 17.2% (n=745). Co-existing intestinal anomalies were the most common, affecting 9.9% (n=429) infants, whereas certain cardiac (6.8%, n=294) and pulmonary (1.7%, n=72) conditions were also identified. Simple gastroschisis represented 89.1% (n=3870) of the group whereas 10.9% (n=474) were complex in nature. Simple and complex patients differed in median length of stay (28 vs 67 days, P<0.01), inpatient mortality (2.9 vs 8.7%, P<0.01) and median inflation-adjusted hospital charges (90,788 dollars vs 197,871 dollars, P<0.01).

CONCLUSIONS

These data represent a national analysis of the largest group of infants with gastroschisis to date which further aids the characterization and understanding of this serious congenital condition.

Outcome analysis for gastroschisis

BACKGROUND/PURPOSE

Several factors are reportedly associated with an adverse outcome in gastroschisis, including mode of delivery, in utero diagnosis, type of closure, concurrent anomalies, intestinal atresia, and necrotizing enterocolitis (NEC). Since 1969, the authors have treated 185 patients who had gastroschisis. The authors analyzed their database to identify variables associated with increased morbidity and mortality.

METHODS

A retrospective study of all patients with gastroschisis treated at our institution in the last 30 years was performed. The characteristics of survivors and nonsurvivors were compared. A logistic regression analysis was performed, with survival as the dependent variable, and the following parameters as independent variables: in utero diagnosis, mode of delivery, gestational age and birth weight, era of repair, type of closure, presence of other associated anomalies, intestinal atresia, and development of necrotizing enterocolitis. Further logistic regression analysis was performed, with various indicators of morbidity as dependent variables. These included development of sepsis, bowel obstruction, and complications related to the closure or to the silo. No attempt at long-term follow-up was made.

RESULTS

A total of 185 infants with gastroschisis were treated at our institution from 1969 to 1999. Mean gestational age was 36.6 weeks, and the mean birth weight was 2,501 g. A total of 21 infants had intestinal atresia. NEC developed in 8 infants. Six infants had other serious anomalies. The overall survival rate was 91%. Survival improved in last 2 decades (94%). There were no differences in gestational age, birth weight and mode of delivery, method of closure, or presence of intestinal atresia between survivors and nonsurvivors. Only the era of repair (P = .002), presence of necrotizing enterocolitis (P = .044), and presence of other major anomalies (P < .001) correlated with mortality in the logistic regression analysis. Sepsis, bowel obstruction, and closure complications accounted for most of the morbidity. Analysis of these three morbidity factors identified low gestational age (P = .038) and development of necrotizing enterocolitis (P = .020) as independent predictors of sepsis. Closure complications were only associated with lower birth weight (P = .006). No predictors of bowel obstruction were identified.

CONCLUSIONS

Mode of delivery, method of closure, birth weight and gestational age, and the presence of intestinal atresia do not appear to correlate with survival in infants with gastroschisis. Only the presence of another major anomaly, the era of repair, and the development of necrotizing enterocolitis were associated with increased mortality. Degree of prematurity and development of enterocolitis were associated with an increased incidence of septic complications. Low birth weight was a marker for closure complications. Type of delivery (vaginal or cesarean section) had no influence on either morbidity or mortality.

Omphalocele and gastroschisis in the State of New York, 1992-1999

BACKGROUND

Variations in the temporal distribution and risk factors for omphalocele and gastroschisis have been suggested although results have not been conclusive. This study examines the trend and risk factors for both conditions among live births in New York State.

METHODS

Analysis of surveillance data from the New York Congenital Malformation Registry for the years 1992-1999.

RESULTS

Five hundred and ninety-five (595) infants with either omphalocele (287) or gastroschisis (308) were identified. It appeared that the prevalence of gastroschisis was rising from 1992-1999, while prevalence of omphalocele was decreasing. Cases of gastroschisis were clustered among younger mothers while the maternal age distribution among omphalocele infants was U-shaped. As compared to Whites, Black infants were more likely to present with omphalocele (OR = 1.73; 95% confidence interval = 1.28-2.33) and Hispanic infants with gastroschisis (OR = 1.50; 95% CI = 1.12-2.00). For both anomalies, residents of rural New York were significantly at higher risk than those living in urban New York. Twenty-three chromosomal aberrations were detected, all among omphalocele babies. Infant survival was substantially greater among gastroschisis (92%) as compared to omphalocele newborn (81%)[p < 0.0001].

CONCLUSIONS

Prevalence of gastroschisis has been on the rise while that of omphalocele has been declining in New York State. Geographical and racial/ethnic variations were observed, further confirming the notion of different etiologies for the two congenital anomalies.

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.

Mode of Delivery and Neonatal Survival of Infants With Isolated Gastroschisis

OBJECTIVE

We sought to compare neonatal survival of infants with gastroschisis by mode of delivery.

METHODS

We conducted a retrospective cohort study on infants with gastroschisis who were delivered in New York State from 1983 through 1999. We compared neonatal mortality between infants born vaginally and those delivered by cesarean using adjusted hazard ratios derived from Cox proportional hazards regression models.

RESULTS

A total of 354 infants were found to have isolated gastroschisis. Of these, 174 were delivered vaginally, whereas 180 were delivered by cesarean. Neonatal mortality was registered among 18 infants (5.1%); 12 (6.9%) in the vaginal and 6 (3.3%) in the cesarean group. After controlling for potential confounders, the risk for neonatal demise was similar in both the vaginal and cesarean subcohorts (adjusted hazard ratio 0.84, 95% confidence interval [CI] 0.29-2.43). Preterm birth was the morbidity pathway that explained the early demise of infants with gastroschisis, irrespective of mode of delivery (adjusted hazard ratio 3.4, 95% CI 1.10-10.4) whereas small for gestational age did not predict mortality (adjusted hazard ratio 1.04, 95% CI 0.13-8.14).

CONCLUSION

In this study the mode of delivery was not found to be associated with neonatal survival of infants with gastroschisis. Preterm birth rather than small for gestational age was the predictor of neonatal death among gastroschisis infants.

LEVEL OF EVIDENCE

III

Epidemiology of gastroschisis in metropolitan Atlanta, 1968 through 2000

BACKGROUND

An increase in the rate of gastroschisis has been documented by birth defects surveillance systems in the United States and in other countries. This study sought to evaluate historical trends in the rate of gastroschisis in Atlanta, Georgia, and to describe the epidemiology of gastroschisis over 33 years.

METHODS

Gastroschisis cases were identified through the Metropolitan Atlanta Congenital Defects Program (MACDP) from 1968 through 2000. Poisson regression techniques were used to evaluate trends over time. Data on covariates were compared for three maternal age groups (< or =19, 20-24, and > or =25 years).

RESULTS

From 1968 through 1975, the rate of gastroschisis was stable at 0.8 per 10,000 births. After 1975, the rate of gastroschisis was 2.3 per 10,000 births with no significant increase observed from 1976 through 2000. The rate of gastroschisis was six times higher among teenage mothers compared with mothers > or =25 years of age. Affected infants born to teenage mothers were less likely to be born to Black mothers compared to White mothers (rate ratio [RR], 0.4; 95% confidence interval [CI], 0.2-0.6). This was also true for mothers 20-24 years of age (RR, 0.5; 95% CI, 0.3-0.8) but not for mothers 25 years of age or older (RR, 1.6; 95% CI, 0.9-2.7).

CONCLUSIONS

An increase in the rate of gastroschisis was observed in the mid-1970s, but no temporal trend has been observed since that time. In light of recent reports of an increasing prevalence of gastroschisis in the United States, continued monitoring of this birth defect is warranted.