Description and mission evaluation of the Hungarian case-control surveillance of congenital abnormalities, 1980-1996

Reducing the Risk of Birth Defects Associated with Maternal Influenza: Insights from a Hungarian Case-Control Study

Influenza viruses can cause several complications during pregnancy. Therefore, we aimed to investigate the effects of influenza on the development of congenital abnormalities (CAs) by analyzing the database of the Hungarian Case-Control Surveillance of Congenital Abnormalities (HCCSCA). In our multicenter, case-control, population-based study, we processed clinician-reported outcomes and diagnoses collected in the HCCSCA. The case group included newborns with different non-chromosomal birth defects, while the controls were newborns without CAs. Maternal influenza, as a risk factor for CAs, was analyzed by using a logistic regression model and odds ratios with 95% confidence intervals (CIs). Our results showed that maternal influenza in the first trimester was associated with increased odds of developing non-chromosomal CAs (OR: 1.41, CI: 1.28-1.55). There were increased odds of neural tube defects (OR: 2.22, CI: 1.78-2.76), orofacial clefts (OR: 2.28, CI: 1.87-2.78), and congenital heart defects (OR: 1.28, CI: 1.10-1.49) after influenza infection. In all cases, we found a protective effect of folic acid supplementation in the first trimester. In summary, the odds of non-chromosomal birth defects are higher after maternal influenza in the first trimester, and folic acid or pregnancy vitamin supplementation and antipyretic therapy may reduce the effect of maternal influenza during the first trimester.

First data from the new, unified database of the Hungarian case-control surveillance of congenital abnormalities

The Hungarian Case-Control Surveillance of Congenital Abnormalities (HCCSCA) is one of the largest case-control data sets of CA-surveillance in the world. We unified all data collected in the HCCSCA between 1980 and 2009 into a new, validated single database that is now open for examination. The details of this unified database are given in this paper. The total number of cases and control newborns is 32,345 and 57,231, respectively. The overall prevalence of CAs recorded in the HCCSCA was 10.7/1000 live-births. Data available for each pregnancy are: CA(s), gender, birth year/month/date, birth weight, gestational age, area of mother's living, maternal age, paternal age, birth order, mother's and father's qualification, employment status and type of employment, mother's marital status, outcome of previous pregnancies, maternal diseases during pregnancy (according to pregnancy months), drug intake during pregnancy (according to pregnancy months), folic acid and/or pregnancy vitamin supplement intake (according to pregnancy months), mother's smoking habits and alcohol consumption patterns. The most frequent anomalies detected were ventricular septal defect (2864), atrial septal defect (1895), polydactyly (1499), hypospadias (1083), and unilateral cleft lip ± palate (961). According to ICD-10, 701 diseases have been found to affect case mothers during pregnancy. Eight hundred and sixteen drugs were identified that had been taken by mothers during pregnancy. The authors are absolutely open for any scientific cooperation based on this database.

Maternal LINE-1 DNA Methylation and Congenital Heart Defects in Down Syndrome

Background: Down syndrome (DS) is one of the most common chromosomal abnormalities associated with congenital heart defects (CHD), with approximately 40 to 60% of cases showing cardiac defects. This study assessed (i) the association between maternal LINE-1 methylation and the occurrence of CHDs in children with DS and (ii) the impact of endogenous maternal factors (MTHFR C677T polymorphism and maternal age) and exogenous maternal factors (cigarette smoking, alcohol intake, medication use, body mass index and dietary habits such as folate intake) on maternal LINE-1 methylation and on the occurrence of CHD in children with DS.

Patients and Methods: The study included 90 mothers of children with DS of maternal origin (49% DS-CHD⁺ mothers/51% DS-CHD⁻ mothers). LINE-1 DNA methylation was analyzed in peripheral blood lymphocytes by quantification of LINE-1 methylation using the MethyLight method. MTHFR C677T polymorphism genotyping was performed using PCR-RFLP.

Results: LINE-1 methylation was not significantly different between DS-CHD⁺ and DS-CHD⁻ mothers (P = 0.997). Combination of MTHFR C677T genotype/diet and BMI were significant independent predictors of LINE-1 DNA methylation in DS-CHD⁺ mothers (β −0.40, P = 0.01 and β −0.32, P = 0.03, respectively). In the analyzed multivariate model (model P = 0.028), these two factors explained around 72% of the variance in LINE-1 DNA methylation in mothers of children with DS and CHD. The group with the highest BMI (≥30 kg/m2) had significantly lower LINE-1 methylation than the group with normal BMI (Bonferroni post hoc P = 0.03) and the overweight group (Bonferroni post hoc P = 0.04). The lowest LINE-1 DNA methylation values were found in DS-CHD⁺ mothers with the CT+TT genotype and a low-folate diet; the values were significantly lower than the values in mothers with the CC genotype and a folate-rich diet (Bonferroni post hoc P = 0.04).

Conclusion: Association between maternal LINE-1 methylation and CHD in children with DS was not found. Study showed that the MTHFR genotype/diet combination and BMI were significantly associated with LINE-1 methylation in mothers of children with DS-CHD⁺. These results highlight the need for a multifactorial approach to assess the roles of endogenous and exogenous maternal factors in maternal LINE-1 DNA methylation and the consequent pathologies in children. More extensive studies in a larger sample may help elucidate these relationships.

When the right (Drug) should be left: Prenatal drug exposure and heterotaxy syndrome

BACKGROUND

Recent studies reported an association between prenatal propylthiouracil exposure and birth defects, including abnormal arrangement across the left-right body axis, suggesting an association with heterotaxy syndrome.

METHODS

This case-control and case-finding study used data from 1981 to 2013 from the EUROCAT birth defect registry in the Northern Netherlands. First, we explored prenatal exposures in heterotaxy syndrome (cases) and Down syndrome (controls). Second, we describe the specific birth defects in offspring of mothers using propylthiouracil (PTU) prenatally.

RESULTS

A total of 66 cases with heterotaxy syndrome (incidence 12.1 per 100,000 pregnancies) and 783 controls with Down syndrome (143.3 per 100,000 pregnancies) were studied. No differences in intoxication use during pregnancy were found between cases and controls, including smoking (28.0% vs. 22.7%; p = 0.40), alcohol (14.0% vs. 26.9%; p = 0.052), and recreational drugs (0 vs. 0.3%; p = 1.00). We found an association between heterotaxy syndrome and prenatal drug exposure to follitropin-alfa (5.6% vs. 1.1%; p = 0.04), and drugs used in nicotine dependence (3.7% vs. 0.2%; p = 0.02). Five mothers used PTU during pregnancy and gave birth to a child with trisomy 18, renal abnormalities, or hypospadias and cardiac defects.

CONCLUSION

This study identified follitropin-alfa and drugs used in nicotine dependence as possible teratogens of heterotaxy syndrome. Our data suggest the possibility that there is an increased risk of birth defects (including renal, urological, and cardiac abnormalities) in children born among mothers taking PTU prenatally, but not for heterotaxy syndrome. Birth Defects Research (Part A) 106:573-579, 2016. © 2016 Wiley Periodicals, Inc.

Maternal factors in the origin of infantile hypertrophic pyloric stenosis: A population-based case-control study

In most patients affected by isolated infantile hypertrophic pyloric stenosis (IHPS) the etiology is largely unknown. Thus, the aim of this study was to estimate possible maternal risk factors in the origin of IHPS. The study samples included 241 cases with IHPS, 357 matched controls and 38,151 population controls without any defect in the population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996. Exposures that had been medically recorded in prenatal maternity logbooks during the critical period of IHPS were evaluated separately. The findings of this case-control study suggested that--beyond the well-known robust male excess (85.5%)--maternal hyperthyroidism (OR with 95% CI: 4.17, 1.53-11.38) and oral nalidixic acid treatment (OR with 95% CI: 6.53, 3.03-14.06) associated with a higher risk for IHPS in their children. In conclusion, our findings suggest that cases with IHPS had mothers with a higher proportion of hyperthyroidism and nalidixic acid treatment during pregnancy.

Birth outcomes of patients with isolated anorectal malformations: A population-based case-control study

In most patients affected by isolated anorectal malformation (IARM) the etiology is largely unknown. Thus, the aim of our project was to analyze possible risk factors for IARM. In the first step, birth outcomes of cases with IARM were analyzed on the basis of maternal socio-demographic variables, and these data are presented in this paper. Gestational age at delivery, birthweight, preterm birth, low birthweight and small for gestational age of cases with IARM were evaluated in the function of maternal age, birth/pregnancy order, marital and employment status of mothers in the population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996. The study samples included 231 live-born cases with IARM, 361 matched and 38 151 population controls without any defect. IARMs are more frequent in males, twins and newborn infants with low birthweight and small-for-gestational-age, the latter being the consequence of intrauterine growth restriction. In addition, mothers of cases were younger but with higher birth order, and had lower socio-economic status. These maternal variables are characteristic for the gypsy population in Hungary. The higher proportion of gypsy women among the mothers of cases with IARM was confirmed during the home visits of the study. Male sex and intrauterine growth restriction of cases, in addition to low socioeconomic status and gypsy origin of mothers may have a role in the risk of IARMs.

Maternal factors in the origin of isolated anorectal malformations - a population-based case-control study

OBJECTIVE

In most patients affected by isolated anorectal malformation (IARM), the etiology is unknown. Thus, the aim of this study was to analyze the possible role of maternal risk factors in the origin of IARM.

METHODS

The study samples included 231 cases with IARM, 361 matched and 38 151 population controls without any defect in the population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996. Cases with IARM were evaluated in the function of maternal diseases and related drug use.

RESULTS

The findings of this case-control study suggested that cases with IARM have an obvious male excess. The mothers of cases with IARM had a lower incidence of severe nausea and vomiting in pregnancy and a higher incidence of acute infectious diseases in the urinary tract.

CONCLUSIONS

Lack of nausea and vomiting in pregnancy and the higher incidence of urinary tract infections may have a role in the development of IARM.

Birth outcomes of male and female patients with infantile hypertrophic pyloric stenosis--a population-based case-control study

OBJECTIVE

Most of the patients are affected by isolated infantile hypertrophic pyloric stenosis (IHPS) beyond the polygenic predisposition, the other factors in the multifactorial etiology are largely unknown. The main characteristic of IHPS is the robust male predominance, thus the aim of this study was to analyze birth outcomes in males and females whether they are different or not.

METHODS

The study samples included 241 cases with IHPS, 357 matched, and 38,151 population controls without any defect in the population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996.

RESULTS

The findings of this case-control study confirmed the well-known strong male excess (85.5%). The mean gestational age was somewhat longer and it is associated with a lower rate of preterm births. Mean birth weight did not show significant differences among the study groups, but the rate of low birthweight was higher in cases with IHPS. However, these differences were found only in males. Thus, intrauterine fetal growth restriction is characteristic only for male cases with IHPS.

CONCLUSIONS

Our study confirmed the well-known obvious male excess of cases with IHPS, but our findings suggest some differences in birth outcomes of male and female cases. Male cases with IHPS had intrauterine fetal growth restriction while females did not. These data may indicate some differences in the pathogenesis of IHPS in males and females.

Sex ratio of congenital abnormalities in the function of maternal age: a population-based study

Maternal age effect is well-known in the origin of numerical chromosomal aberrations and some isolated congenital abnormalities (CAs). The sex ratio (SR), i.e. number of males divided by the number of males and females together, of most CAs deviates from the SR of newborn population (0.51). The objective of this analysis was to evaluate the possible association of maternal age with the SR of isolated CAs in a population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996. First, SR of 24 CA entities/groups was estimated in 21,494 patients with isolated CA. In the next step SR of different maternal age groups was compared to the mean SR of the given CA-groups. The SR of four CA-groups showed some deviation in certain maternal age groups. Cases with anencephaly had female excess in young mothers (<25 years). Cases with skull's CAs particularly craniosynostosis had a male excess in cases born to women over 30 years. Two other CA groups (cleft lip ± palate and valvar pulmonic stenosis within the group of right-sided obstructive defect of heart) had significant deviation in SR of certain maternal age groups from the mean SR, but these deviations were not harmonized with joining age groups and thus were considered as a chance effect due to multiple testing. In conclusion, our study did not suggest that in general SR of isolated CAs might be modified by certain maternal age groups with some exception such as anencephaly and craniosynostosis.

Higher risk of orofacial clefts in children born to mothers with angina pectoris: a population-based case-control study

Previously an unexpected association of maternal angina pectoris (MAP) during pregnancy with a higher risk of orofacial clefts in their children was found. There were three objectives of this study: (i) to evaluate the validity of MAP-diagnoses in the previous study and the recent history of mothers with MAP in a follow-up study; (ii) to estimate the prevalence of other congenital abnormalities in the offspring of mothers with MAP; and (iii) to analyze the possible effect of confounders for the risk of orofacial clefts. The large dataset of population-based Hungarian Case-Control Surveillance System of Congenital Abnormalities, 1980-1996 was evaluated including 22 843 cases with congenital abnormalities and 38 151 controls without any defect. Twenty-two cases (0.10%) and 12 controls (0.03%) were born to mothers with medically recorded MAP (odds ratio [OR] with 95% confidence interval [CI]: 3.7, 1.8-7.3). Of 22 cases, six had isolated cleft lip ± palate (OR with 95% CI: 13.3, 4.9-35.9) and two were affected with isolated cleft palate (OR with 95% CI: 10.5, 2.3-47.6). The diagnosis of MAP was confirmed in seven women visited at home in 2009-2010, two had recent myocardial infarction and five were smokers. There was no higher risk for other congenital abnormalities. In conclusion the higher risk of orofacial clefts was confirmed in the children of mothers with MAP and smoking may trigger the genetic predisposition of both MAP and orofacial clefts. However, the number of cases was limited and therefore further studies are needed to confirm or reject this theoretically and practically important observation.

Use of inhaled and oral corticosteroids in pregnancy and the risk of malformations or miscarriage

Corticosteroids are potent anti-inflammatory and immunosuppressive drugs, which sometimes must be given to pregnant women. Corticosteroids have been suspected to be teratogenic for many years; however, there is conflicting evidence regarding the association. Based on a literature review of three databases, this MiniReview provides an overview of inhaled and oral corticosteroid use in pregnancy with specific emphasis on the association between use of corticosteroids during pregnancy and risk of miscarriage and congenital malformations in offspring. The use of corticosteroids among pregnant women ranged from 0.2% to 10% and increased nearly two times in recent years. Taken together, the evidence suggests that the use of corticosteroids in early pregnancy is not associated with an increased risk of congenital malformations overall or oral clefts in offspring; at the same time, published estimates are inconsistent. The use of inhaled corticosteroids was associated with a slightly increased risk of miscarriage, whereas the use of oral corticosteroids was not; however, confounding by indication could not be ruled out.

Distribution of maternal age and birth order groups in cases with unclassified multiple congenital abnormalities according to the number of component abnormalities: a national population-based case-control study

BACKGROUND

Multiple congenital abnormalities are caused by chromosomal aberrations, mutant major genes and teratogens. A minor proportion of these patients are identified as syndromes but the major part belonging to the group of unclassified multiple CAs (UMCAs). The main objective of this study was to evaluate the maternal age and birth order in pregnant women who had offspring affected with UMCA. The strong association between numerical chromosomal aberrations, e.g., Down syndrome and advanced maternal age is well-known and tested here.

METHODS

The Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980 to 1996, yielded a large population-based national data set with 22,843 malformed newborns or fetuses ("informative cases") included 1349 UMCA cases with their 2407 matched controls. Case-control comparison of maternal age and birth order was made for cases with UMCA, stratified by component numbers and their controls. In addition, 834 cases with Down syndrome were compared to 1432 matched controls.

RESULTS

The well-known advanced maternal age with the higher risk for Down syndrome was confirmed. The findings of the study suggest that the young age of mothers associates with the higher risk of UMCA, in addition birth order 4 or more associates with the higher risk for UMCA with 2 and 3 component CAs.

CONCLUSION

This study was the first to analyze the possible maternal and birth order effect for cases with UMCA, and the young age and higher birth order associated with a higher risk for UMCA.

Association of certain chronic maternal diseases with the risk of specific congenital heart defects: a population-based study

OBJECTIVE

Previous epidemiological studies have evaluated cases with all congenital heart defects (CHDs), rather than analysing different types of CHD. The objective of this study was to evaluate the possible association of certain chronic maternal diseases with the risk of different types of CHD, because the role of possible environmental factors in the origin of CHDs is unclear in the vast majority of patients.

STUDY DESIGN

Different types of CHD, diagnosed after lethal outcome (autopsy report) or after surgical intervention (catheter or correction), were evaluated in order to estimate the possible role of chronic maternal diseases in their origin. This analysis was based on the rates of medically recorded chronic maternal diseases in 3562 live-born cases with CHDs, 38,151 population controls without any birth defects, and 16,602 malformed controls with other isolated congenital abnormalities, using the data set of the population-based Hungarian Case-Control Surveillance of Congenital Abnormalities (1980-1996).

RESULTS

Maternal epilepsy treated with carbamazepine and migraine were found to be associated with higher risk of ventricular septal defect; panic disorders were associated with higher risk of hypoplastic left heart; type I diabetes mellitus was associated with higher risk of coarctation of the aorta; chronic hypertension was associated with higher risk of ventricular septal defect, common atrioventricular canal and common truncus; and paroxysmal supraventricular tachycardia was associated with higher risk of atrial septal defect secundum, common atrioventricular canal and ventricular septal defect.

CONCLUSION

In conclusion, certain chronic maternal diseases were found to be associated with higher risk of specific CHDs. Appropriate treatment of these diseases may help to prevent these CHDs.

Characteristics of boys with the so-called true undescended testis diagnosed at the third postnatal month--a population-based case-control study

OBJECTIVE

Undescended testis (cryptorchidism) is a common congenital abnormality of male genital organs diagnosed at birth followed with frequent postnatal descensus. However, the so-called isolated true undescended testis (ITUT) diagnosed at the third postnatal month seems to be an independent defect-entity, and this hypothesis was planned to confirm or reject in the study.

METHOD

The evaluation of birth outcomes and maternal socio-demographic data of cases with ITUT in the population-based large dataset of the Hungarian Congenital Abnormality Registry.

RESULTS

There was a higher rate of preterm birth and particularly of low birthweight in 2052 cases with ITUT compared to 24,814 population male controls without any defects. The rate of twins was not higher in cases with older mothers, higher birth order and lower socio-economic status. The comparison of data of boys with undescended testis diagnosed at birth found in the previous study and with ITUT in this study confirmed our hypothesis.

CONCLUSIONS

Undescended testis can be differentiated into two subgroups: boys with frequent postnatal descensus mainly after preterm delivery and boys with ITUT without postnatal testis descensus with frequent intrauterine growth restriction, older mothers with higher birth order and low socio-economic status.

Possible association of maternal factors with the higher risk of isolated true undescended testis: A population-based case-control study

The objective of the study was to evaluate the possible association of maternal factors with the risk of isolated true undescended testis (ITUT) diagnosed at the third postnatal month because our knowledge is limited regarding the origin of ITUT. Acute and chronic diseases with related drug treatments were compared in the mothers of 2052 cases with ITUT, 24,814 male controls without any defects and 12,082 malformed male controls with other isolated defects in the population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996. Prospective medically recorded endometriosis before conception of the study pregnancy in the mothers of 39 cases was associated with a higher risk of ITUT in their sons (odds ratio (OR) with 95% confidence interval [CI]: 2.42, 1.71-3.42). Dihydrogesterone treatment in the first trimester of pregnancy also showed association with the higher risk of ITUT but based on only five pregnant women. In conclusion, endometriosis before pregnancy may have a role in the origin of ITUT.

Association of young and advanced age of pregnant women with the risk of isolated congenital abnormalities in Hungary - a population-based case-matched control study

OBJECTIVE

To analyze the possible association of maternal age with the risk of all congenital abnormalities (CAs) in a population-based large case-matched control data set.

METHODS

The Hungarian Case-Control Surveillance of Congenital Abnormalities included 21,494 cases with isolated CA and their 34,311 matched controls. First the distribution of maternal age groups in 24 CA-groups and their matched controls was compared. In the second step, young (19 years or less) and advanced (35 years or more) age groups were compared. Finally, the subgroups of neural-tube defects, congenital heart defects and abdominal wall's CA were evaluated separately.

RESULTS

A higher risk of gastroschisis, congenital heart defects, particularly left-sided obstructive defects, undescended testis and clubfoot was found in the youngest age group (19 years or less) of cases. The higher proportion of pregnant women with advanced age (i.e. 35 years or more) showed only a borderline excess in cases with clubfoot. The so-called U-shaped risk of maternal age distribution was found in cases with clubfoot and in the total group of isolated CAs.

CONCLUSIONS

The maternal age is a contributing factor to the origin of some isolated CAs mainly in young pregnant women.

Birth outcomes of cases with conotruncal defects of heart - a population-based case-control study

OBJECTIVE

The aim of this study was to evaluate the birth outcomes of cases with four types of conotruncal defects (CTDs), i.e. common truncus, transposition of great arteries, tetralogy of Fallot and double-outlet right ventricle.

METHODS

Birth outcomes of 597 live-born cases with CTD and 38,151 population controls without any defects were compared in the population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities completed by socio-demographic variables of their mothers.

RESULTS

There was a male excess in cases with CTD (56.8%) with the same mean gestational age (39.4 versus 39.4 weeks) and preterm birth rate (8.2 versus 9.2%), but their mean birth weight was smaller (3077 versus 3276 g) with a high rate of low birthweight (14.6 versus 5.7%) compared to the birth outcomes of population controls. These data indicate intrauterine growth restriction of fetuses affected with transposition of great arteries, tetralogy of Fallot and double-outlet right ventricle particularly in females, while there were a shorter mean gestational age and smaller mean birth weigh in cases with common truncus.

CONCLUSIONS

In general CTD, except common truncus, had no effect for gestational age but associated with a high risk for intrauterine fetal growth restriction particularly in female cases.

Risk and protective factors in the origin of atrial septal defect secundum--national population-based case-control study

The aim of this study was to assess the risk factors in the origin of lethal or surgically corrected isolated atrial septal defect secundum. The population-based Hungarian Case-Control Surveillance of Congenital Abnormalities (conducted between 1980 and 1996) comprised 472 atrial septal defect secundum cases, 678 matched controls and 38,151 available controls without any defects; in addition, 21,022 malformed controls with other isolated defects. Medically recorded chronic disorders in the prenatal maternity logbook were evaluated, while acute maternal diseases, drug treatments and pregnancy supplements were analyzed on the basis of both prospective medically recorded data and retrospective maternal information. Acute pelvic inflammatory disease, paroxysmal supraventricular tachycardia and phenolphthalein treatment due to severe constipation of mothers were shown to contribute to the development of atrial septal defect secundum of their children. High doses of folic acid in early pregnancy had positively influenced a minor part of isolated atrial septal defect secundum in foetuses. In conclusion, the obvious genetic predisposition for atrial septal defect secundum is connected with maternal paroxysmal supraventricular tachycardia and triggered by acute pelvic inflammatory diseases and phenolphthalein treatment, while the manifestation of atrial septal defect secundum can be reduced by high doses of folic acid supplementation in early pregnancy.

Maternal risk factors in the origin of isolated hypospadias: a population-based case-control study

The birth prevalence of hypospadias increased in Hungary during the last decades, thus the aim of this study was to analyze the possible role of maternal risk factors in the origin of isolated hypospadias (IHS). The incidence/prevalence of acute and chronic maternal diseases with related drug treatments were compared in the mothers of cases with IHS, population controls without defect and malformed controls affected with other isolated abnormalities in the population-based Hungarian Case-Control Surveillance of Congenital Abnormalities including 3038 cases with IHS, 24 814 population male controls without any defects and 11 096 malformed male controls with other isolated defect. Among exposures, prospective medically recorded chronic diseases and medically recorded or retrospective maternal information regarding acute diseases and drug treatments were evaluated in the study groups. Maternal epilepsy due to the treatment of valproate (odds ratio [OR] with 95% confidence interval [CI]: 1.97, 1.07-3.61) and cervical erosion (4.09, 1.84-9.12) were associated with a higher risk of IHS. In addition, there was an association of oral nystatin (1.94, 1.22-3.09), lynestrenol (26.66, 8.69-81.80) and ethynilestradiol (3.51, 1.61-7.67) treatments in the mothers of cases with a higher risk for IHS. In conclusion, maternal cervical erosion, valproate, nystatin, lynestrenol and ethynilestradiol associated with a higher risk for IHS.

50 years of the Hungarian Congenital Abnormality Registry

The mandatory notification of patients ("cases") with different congenital abnormalities (CAs) diagnosed from birth until the end of the first postnatal year by medical doctors was ordered by the Ministry of Health in Hungary in 1962 and this CA-registry was continued as the Hungarian Congenital Abnormality Registry (HCAR) based on the international recommendation from 1970. The primary objective of the HCAR has been to determine the baseline birth prevalence rate of different CAs as reliably as possible, with three secondary objectives: (i) to detect temporal and/or spatial clusters of CAs; (ii) to evaluate increasing or decreasing time trends of CAs; and (iii) to assist in the planning of medical and social services for children and families affected by CA so that appropriate resources are allocated efficiently and effectively. This paper summarizes the activities and the evolution of the HCAR over the past 50 years (1962-2011) including the Hungarian Case-Control Surveillance of Congenital Abnormalities for postmarketing surveillance of drug teratogenicity and prevention of CAs; the special evaluation of unidentified multiple CAs; the Hungarian Surveillance of Germinal Mutations and several international collaborations. In conclusion, Hungary enjoyed optimal conditions for the HCAR due to a centralized state health system; all deliveries took place in inpatient clinics; the quality of pediatric care was high and pediatricians notified most CAs. Autopsy was mandatory in infant death, the staff of the HCAR did not consider this CA-registry only as a statistical system but the Hungarian Center for Congenital Anomaly Control and the Hungarian Case-Control Surveillance of Congenital Abnormalities based on the HCAR worked with close collaboration with the parents in order to promote the possible good quality of life of their affected children and to prevent their risk of recurrence.

Maternal hypertension with nifedipine treatment associated with a higher risk for right-sided obstructive defects of the heart: a population-based case-control study

OBJECTIVE

To establish possible aetiological factors contributing to congenital heart defects (CHD) overall and separately for different types of CHD, as causes are unknown for the vast majority of patients.

DESIGN

To estimate a possible association with maternal diseases and related drug treatments as exposures in the mothers of cases with right-sided obstructive defects of the heart (RSODH).

SETTING

A large population-based Hungarian Case-Control Surveillance of Congenital Abnormalities data set.

PATIENTS

Newborn infants with four types of RSODH based on autopsy or surgical records.

INTERVENTIONS

Comparison of 200 live-born cases with RSODH including 72 (36.0%) with pulmonary valve stenosis, 13 (6.5%) with tricuspid atresia/stenosis, 7 (3.5%) with Ebstein's anomaly and 108 (54.0%) with pulmonary atresia, with 304 matched controls and 38 151 population controls without any defects.

MAIN OUTCOME MEASURES

Risk of any RSODH and risk of each type of RSODH.

RESULTS

High blood pressure, particularly chronic hypertension with nifedipine treatment, was associated with a risk for RSODH (OR 7.03, 95% CI 3.13 to 13.84). High doses of folic acid reduced the birth prevalence of pulmonary atresia (OR 0.29, 95% CI 0.16 to 0.53).

CONCLUSIONS

The multifactorial threshold model provides the best explanation for the origins of RSODH. Genetic predisposition may be triggered by maternal hypertension with nifedipine treatment, while the risk for pulmonary atresia is reduced by high doses of folic acid in early pregnancy.

Risk factors in the origin of congenital left-ventricular outflow-tract obstruction defects of the heart: a population-based case-control study

The aim of our project was to study possible etiological factors in the origin of congenital heart defects (CHDs) because in the majority of patients the underlying causes are unclear. Cases with different CHD entities as homogeneously as possible were planned for evaluation in the population-based large data set of the Hungarian Case Control Surveillance of Congenital Abnormalities. Dead or surgically corrected 302 live-born cases with different types of left-ventricular outflow tract obstructive defects (LVOT, i.e., valvular aortic stenosis 76, hypoplastic left heart syndrome 76, coarctation of the aorta 113, and other congenital anomalies of aorta 32) were compared with 469 matched controls, 38,151 controls without any defects, and 20,750 malformed controls with other isolated defects. Medically recorded pregnancy complications and chronic diseases were evaluated based on prenatal maternity logbooks, whereas acute diseases, drug treatments, and folic acid/multivitamin supplementation were analyzed both on the basis of retrospective maternal information and medical records. The results of the study showed the role of maternal diabetes in the origin of LVOT in general, while panic disorder was associated with a higher risk of hypoplastic left heart syndrome and ampicillin treatment with a higher risk of coarctation of the aorta (COA). High doses of folic acid had a protective effect regarding the manifestation of LVOT, particularly COA. In conclusion, only a minor portion of causes was shown in our study; thus, further studies are needed to understand better the underlying causal factors in the origin of LVOT.

Folate deficiency and folic acid supplementation: the prevention of neural-tube defects and congenital heart defects

Diet, particularly vitamin deficiency, is associated with the risk of birth defects. The aim of this review paper is to show the characteristics of common and severe neural-tube defects together with congenital heart defects (CHD) as vitamin deficiencies play a role in their origin. The findings of the Hungarian intervention (randomized double-blind and cohort controlled) trials indicated that periconceptional folic acid (FA)-containing multivitamin supplementation prevented the major proportion (about 90%) of neural-tube defects (NTD) as well as a certain proportion (about 40%) of congenital heart defects. Finally the benefits and drawbacks of three main practical applications of folic acid/multivitamin treatment such as (i) dietary intake; (ii) periconceptional supplementation; and (iii) flour fortification are discussed. The conclusion arrived at is indeed confirmation of Benjamin Franklin's statement: "An ounce of prevention is better than a pound of care".

Risk and protective factors in the origin of conotruncal defects of heart--a population-based case-control study

Congenital heart defect (CHD) cases have been evaluated together as a group in some previous epidemiological studies. However, different CHD entities have different etiologies, and the underlying causes are unclear in the vast majority of patients. Thus the aim of this study was to analyze the possible association of different maternal diseases with the risk of four types of conotruncal defects (CTD), that is, truncus arteriosus, d-transposition of the great arteries, tetralogy of Fallot, and double-outlet right ventricle based on autopsy or surgical report diagnosis. Acute and chronic diseases with related drug treatments and peri-conceptual folic acid or multivitamin supplementations were compared in mothers of 598 CTD cases, of 902 matched controls, and 38,151 population controls without any defects, and with 20,896 malformed controls with other isolated non-cardiac defects in the population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities. Mothers who had medically recorded influenza and the common cold with secondary complications in the prenatal maternity logbook during the second and/or third gestational months were associated with a higher risk of CTD (OR with 95% CI: 2.22, 1.19-3.88). The common denominator of these maternal diseases may be high fever, which could be prevented by antifever therapies. On the other hand, high doses of medically recorded folic acid in early pregnancy were able to reduce the birth prevalence of CTD (OR with 95% CI: 0.54, 0.39-0.73), and this reduction was significant in transposition of the great arteries (0.46, 0.29-0.71) as well. In conclusion, high fever related maternal diseases may have a role in the origin of CTD, while high doses of folic acid in early pregnancy were able to reduce of CTD, particularly transposition of great vessels.

Birth outcomes of cases with isolated atrial septal defect type II--a population-based case-control study

OBJECTIVES

In general, epidemiological studies have evaluated cases with congenital cardiovascular abnormalities together. The aim of this study is to describe the birth outcomes of cases with isolated/single atrial septal defect type II (ASD-II, i.e. only a fossa ovalis defect) after surgical correction or lethal outcome in the light of maternal sociodemographic data.

DESIGN

Comparison of birth outcomes and maternal characteristics of cases with ASD-II and controls without defect.

SETTING

The population-based Hungarian Case-Control Surveillance of Congenital Abnormalities.

POPULATION

Hungarian newborn infants with or without ASD-II.

METHODS

Medically recorded birth outcomes, maternal age and birth order were evaluated. Marital and employment status was based on maternal information. The lifestyle factors were analyzed in a subsample of mothers visited at home based on a personal interview with mothers and their close relatives, and the family consensus was accepted.

MAIN OUTCOME MEASURES

Mean gestational age at delivery and birthweight, rate of preterm birth and low birthweight, maternal age, birth order, marital and employment status.

RESULTS

The evaluation of 471 cases with ASD-II and 38,151 controls without any defects showed a female excess in cases with ASD-II, having shorter gestational age and lower mean birthweight, and thus a higher rate of preterm births and low birthweight.

CONCLUSIONS

Intrauterine growth restriction and shorter gestational age were found in cases with ASD-II, particularly in female children. These factors may have a general developmental process in which there was not closure of the foramen ovale, thus echocardiographic screening of these babies might be of value.

Short-Term Oral Diazepam Treatment during Pregnancy : A Population-Based Teratological Case-Control Study

OBJECTIVE

To study the possible human teratogenicity of short-term (generally 3 weeks) oral diazepam treatment during pregnancy.

DESIGN AND SETTING

A matched case-population control pair analysis based on the total (maternal self-reported and medically recorded) or medically recorded diazepam treatments, in addition to a comparison between cases and patient controls in the population-based large data set of the Hungarian Case-Control Surveillance of Congenital Abnormalities from 1980 to 1996.

STUDY PARTICIPANTS

38 151 population-control neonates without any congenital abnormalities, 22 865 neonates or fetuses with congenital abnormalities (cases) and 812 neonates or fetuses with Down's syndrome (patient controls).

MAIN OUTCOME MEASURES

24 congenital abnormality groups.

RESULTS

2746 (12.0%) cases, 4130 (10.8%) population controls and 97 (11.9%) patient controls were born to mothers treated with diazepam during pregnancy. The matched case-population control pair analysis showed a higher rate of limb deficiencies, rectal-anal atresia/stenosis, cardiovascular malformations and multiple congenital abnormalities after diazepam use during the second and third months of gestation, i.e. in the critical period for most major congenital abnormalities, based on maternal self-reported and medically recorded information. However, the evaluation of only medically recorded diazepam use did not indicate a higher use of diazepam in any congenital abnormality group. Thus, the higher occurrence of diazepam treatment among cases in the primary analysis may be due to the lower proportion of maternal self-reported diazepam intake in the population control group, i.e. recall bias. The comparison of diazepam use between 24 congenital abnormality groups and patient controls as the referent group showed a difference only in the group of intestinal atresia/stenosis, probably due to chance error caused by multiple comparison.

CONCLUSIONS

Short-term diazepam treatment in usual therapeutic doses during pregnancy did not present any detectable teratogenic risk to the fetus.

Rate of preterm birth in pregnant women with vitamin E treatment: a population-based study

OBJECTIVE

Vitamin E is frequently used for prevention/treatment of repeated or threatened abortion and threatened preterm delivery in Hungarian pregnant women, though, internationally this old-fashion method is not recommended.

METHODS

The rate of preterm birth of newborns in pregnant women with high dose (estimated daily dose 450 mg) vitamin E treatment or without this treatment was compared in the population-based large data set of the Hungarian Case-Control Surveillance System of Congenital Abnormalities.

RESULTS

Of 38,151 newborns with any defect, 2,287 (6.0%) had mothers with vitamin E treatment. Pregnant women with vitamin E treatment had very high rate of threatened abortion (43.6% vs. 15.4%) and high rate of threatened preterm delivery (27.5% vs. 13.4%) compared to pregnant women without vitamin E treatment. Nevertheless, the gestational age at delivery was 0.2 week longer and rate of preterm births was lower in the newborns of pregnant women with vitamin E treatment (6.6% vs. 9.3%; adjusted OR with 95% CI: 0.71, 0.63-0.84). This preterm preventive effect of vitamin E treatment could not be explained by known confounders, though folic acid/multivitamins also reduced the rate of preterm birth.

CONCLUSION

The study showed nearly 30% reduction in preterm births of pregnant women with vitamin E treatment.

Possible multifactorial etiology of isolated microtia/anotia--a population-based study

OBJECTIVE

To test the possible multifactorial-threshold model in the origin of isolated microtia/anotia (IMA).

METHOD

The observed number of IMA in the first degree relatives of cases affected was compared with the expected number of affected first degree relatives based on the multifactorial-threshold model in the population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996.

RESULTS

Of 354 cases with IMA, 14 (4.0%) had the affected first degree relatives with IMA. There was a low and similar rate of familial occurrence of IMA in parents and siblings of cases. The observed numbers of affected first degree relatives of cases with IMA and their expected numbers did not show significant difference (p=0.47). Some other findings (e.g. male excess and the interaction of triggering environmental factors with polygenic predisposition) confirmed this hypothesis.

CONCLUSIONS

The familial pattern of cases with IMA does not reject the hypothesis that the multifactorial-threshold model, i.e. gene-environmental interaction, may be the explanation for the origin of this congenital abnormality group, although the number of familial cases was quite small in the study.

Association between uterus uni/bicornis in pregnant women and postural deformities in their offspring

OBJECTIVE

The objective of the investigation was to study the possible association between uterus uni- or bicornis in pregnant women and structural birth defects (ie, congenital abnormalities) in their offspring.

STUDY DESIGN

There were 22,843 cases with congenital abnormality recorded in the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996. These subjects were matched to 38,151 controls without any defect. Prevalence of medically recorded uterus uni/bicornis in the prenatal maternity logbook in the mothers of subjects with different congenital abnormalities and of their matched controls without any defect were compared.

RESULTS

Fifty-seven (0.25%) subjects and 67 (0.18%) controls had mothers with uterus uni/bicornis. There was a significant association of uterus uni/bicornis in pregnant women with a higher risk of total group of congenital abnormalities (adjusted odds ratio, 1.5; 95% confidence interval, 1.1-2.2) explained mainly by a significantly higher risk of clubfoot and particularly postural deformity association in their children (adjusted odds ratio, 4.7; 95% confidence interval, 2.4-9.1).

CONCLUSION

Pregnant women with a uni/bicornis uterus have a significantly higher risk of clubfoot and postural deformity association.

Interpretation of controversial teratogenic findings of drugs such as phenobarbital

Objective. To check the debated association between phenobarbital treatment during pregnancy and risk for congenital abnormalities (CAs) in their children. Study Design. It is a comparison of phenobarbital treatment in the mothers of cases with CA and matched controls without CAs in the Hungarian Case-Control Surveillance System of Congenital Abnormalities. Results. Of 22,843 cases with CA, 149 (0.65%) had mothers with phenobarbital treatment, while of 38,151 control newborn infants without CA, 209 (0.55%) were born to mothers with phenobarbital treatment (100-400 mg daily) (OR with 95% CI : 1.3, 1.1-1.7). Of 16 CA groups, only hypospadias had a higher risk after phenobarbital treatment in the critical period of this CA (OR with 95% CI : 2.4, 1.1-5.4). However, if only medically recorded phenobarbital treatments were evaluated and multiple testing bias was considered, this association would disappear. Conclusions. This study stresses the importance of the exclusion of recall bias and multiple testing bias.

Association of drug treatments in pregnant women with the risk of external ear congenital abnormalities in their offspring: a population-based case-control study

The objective of this study was to evaluate the possible association of drug treatments in pregnant women with a higher risk of congenital abnormalities of the external ear, particularly microtia/anotia, in their children. The frequency of drug treatments was compared in the mothers of cases with isolated or multiple (syndromic) ear abnormalities and in the mothers of three different controls: controls matched to cases, all controls (these controls had no defects) and malformed controls in the population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities. There was no significantly higher use of any drug in the mothers of 354 cases with isolated external ear abnormalities than in the mothers of different controls. However, of 156 cases with multiple ear abnormalities, 11 had mothers with hydroxyethylrutosidea treatment and a characteristic pattern of congenital abnormalities was found in these children. Four cases with multiple ear abnormalities were born to epileptic mothers treated with valproate, phenytoin and polytherapy in two cases. Drug treatments are not important in the origin of isolated ear abnormalities. However, a higher risk of multiple ear abnormalities was found in children born to mothers with treatment of hydroxyethylrutosidea or antiepileptic drugs during pregnancy.

Distribution of multiple congenital abnormalities including anotia and microtia

To evaluate cases with unclassified multiple congenital abnormalities including microtia and anotia as component congenital abnormalities in order to reveal the characteristic pattern of other associated component congenital abnormalities and to make an attempt to establish a registry diagnosis on the pattern of associated congenital abnormalities and to stimulate the establishment of an international registry of cases with unclassified multiple congenital abnormalities comprising of microtia and anotia. Methods: The large population-based dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980–1996. Results: A total of 156 cases with unclassified multiple congenital abnormalities including microtia and anotia were analyzed according to the number of 2–9 component congenital abnormalities. The comparison of the distribution and frequency of component congenital abnormalities in these cases showed significant differences from the data of other unclassified multiple congenital abnormalities. Of the 156 cases, registry diagnosis was possible in 48 (30.8%) cases. Conclusions: The evaluation of available dataset of unclassified multiple anotia and microtia may help the delineation of new syndromes and associations with better prognosis and recurrence risk estimation, thus finally a better chance for their prevention. Orv. Hetil., 2011, 152, 1399–1416.

Primary prevention of neural-tube defects and some other congenital abnormalities by folic acid and multivitamins: history, missed opportunity and tasks

The history of intervention trials of periconception folic acid with multivitamin and folic acid supplementation in women has shown a recent breakthrough in the primary prevention of structural birth defects, namely neural-tube defects and some other congenital abnormalities. Recently, some studies have demonstrated the efficacy of this new method in reducing congenital abnormalities with specific origin; for example, in the offspring of diabetic and epileptic mothers, and in pregnancy with high fever. The benefits and drawbacks of four possible uses of periconception folate/folic acid and multivitamin supplementation are discussed: we believe there has been a missed opportunity to implement this preventive approach in medical practice. The four methods are as follows: (i) dietary intake of folate and other vitamins, (ii) periconception folic acid/multivitamin supplementation, (iii) food fortification with folic acid, and (iv) the combination of oral contraceptives with 6S-5-methytetrahydrofolate ('folate').

No association of maternal vitamin E intake with higher risk of cardiovascular malformations in children: a population-based case-control study

OBJECTIVE

In Hungary, vitamin E is frequently used to prevent repeated or threatened abortion. A previous study showed a higher risk of cardiovascular malformations in the children of pregnant women who had a high vitamin E intake either in their diet or by taking supplements. The objective was to examine this association.

METHODS

The Hungarian Case-Control Surveillance System of Congenital Abnormalities, 1980-1996, is a large, population-based dataset including 22,843 cases with congenital abnormalities, 38,151 healthy controls matched to the cases, and 834 patient controls with Down syndrome. Vitamin E treatment was compared in the mothers of these children.

RESULTS

The mothers of 1418 cases with congenital abnormalities (6.2%), 2267 controls (6.0%) and 43 patient controls (5.2%) had vitamin E treatment during pregnancy. A preliminary comparison of cases and controls showed a higher risk for four congenital abnormality groups, including cardiovascular malformations. However, if only prospectively and medically recorded vitamin E treatments in the prenatal maternity logbook were evaluated during the critical period of different congenital abnormalities, the higher risk for these congenital abnormalities was not found.

CONCLUSIONS

The results of this study were based on relatively high-dose vitamin E intake in pregnant women and were not able to confirm the previously reported teratogenic effect of vitamin E.

Prevalence at birth of congenital abnormalities of external ears in Hungary

The objective of the study was to estimate the prevalence at birth and epidemiologic characteristics of patients/cases with both isolated and multiple “syndromic” external ear congenital abnormalities (CAs) in Hungary. The Hungarian Congenital Abnormality Registry, 1980–1996, included 649 cases with isolated external ear CAs, while the number of cases with unclassified multiple CA, including ear CAs, was 331. Thus the prevalence at birth of cases with isolated external ear CAs and unclassified multiple CAs was 0.30 and 0.15, respectively, for a total 0.46 per 1000 births. After reevaluation of reported 354 cases with isolated external ears CAs in the Hungarian Case-Control Surveillance of Congenital Abnormalities, 74 (20.9%) and 236 (66.7%) were affected with mild and severe microtia, while 24 (6.8%) had anotia. The fourth group included 20 cases with the combination of anotia/microtia and external/middle ear CAs. Isolated ear CAs showed a slight male excess (54.0%) and strong predominance of unilateral manifestation (93.4%). Multiple ear CAs showed a stronger male excess (65.4%) and less frequent unilateral affection (62.2%). In conclusion, ear CAs had a low diagnostic validity; thus it was necessary to reassess the data and to reclassify several cases.