Risk of congenital heart defects associated with assisted reproductive technologies: a population-based evaluation.

AIMS: To estimate the risk of congenital heart defects (CHD) associated with assisted reproductive technologies (ART). METHODS AND RESULTS: We used data from the Paris Registry of Congenital Malformations on 5493 cases of CHD and 3847 malformed controls for which no associations with ART were reported in the literature. Assisted reproductive technologies included inductors of ovulation only, in vitro fertilization, and intracytoplasmic sperm injection. Exposure to ART was higher for cases than controls (4.7 vs. 3.6%, P= 0.008) and was associated with a 40% increase in the maternal age, socioeconomic factors, and year of birth-adjusted odds of CHD without chromosomal abnormalities [adjusted odds ratio (OR) 1.4, 95% confidence interval (CI) 1.1-1.7]. Assisted reproductive technologies were specifically associated with significant increases in the odds of malformations of the outflow tracts and ventriculoarterial connections (adjusted OR 1.7, 95% CI 1.2-2.4) and of cardiac neural crest defects and double outlet right ventricle (adjusted OR 1.7, 95% CI 1.1-2.7). In general, we found specific associations between methods of ART and subcategories of CHD. CONCLUSION: Cases with CHD were more likely to have been conceived following ART when compared with malformed controls. This higher risk for CHD varied specifically according to the method of ART and the type of CHD and may be due to ART per se and/or the underlying infertility of couples.

Frequency of holoprosencephaly in the International Clearinghouse Birth Defects Surveillance Systems: searching for population variations.

BACKGROUND: Holoprosencephaly (HPE) is a developmental field defect of the brain that results in incomplete separation of the cerebral hemispheres that includes less severe phenotypes, such as arhinencephaly and single median maxillary central incisor. Information on the epidemiology of HPE is limited, both because few population-based studies have been reported, and because small studies must observe a greater number of years in order to accumulate sufficient numbers of births for a reliable estimate. METHODS: We collected data from 2000 through 2004 from 24 of the 46 Birth Defects Registry Members of the International Clearinghouse for Birth Defects Surveillance and Research. This study is based on more than 7 million births in various areas from North and South America, Europe, and Australia. RESULTS: A total of 963 HPE cases were registered, yielding an overall prevalence of 1.31 per 10,000 births. Because the estimate was heterogeneous, possible causes of variations among populations were analyzed: random variation, under-reporting and over-reporting bias, variation in proportion of termination of pregnancies among all registered cases and real differences among populations. CONCLUSIONS: The data do not suggest large differences in total prevalence of HPE among the studied populations that would be useful to generate etiological hypotheses.

Reproductive health and pregnancy outcomes among French gulf war veterans.

BACKGROUND: Since 1993, many studies on the health of Persian Gulf War veterans (PGWVs) have been undertaken. Some authors have concluded that an association exists between Gulf War service and reported infertility or miscarriage, but that effects on PGWV's children were limited. The present study's objective was to describe the reproductive outcome and health of offspring of French Gulf War veterans. METHODS: The French Study on the Persian Gulf War (PGW) and its Health Consequences is an exhaustive cross-sectional study on all French PGWVs conducted from 2002 to 2004. Data were collected by postal self-administered questionnaire. A case-control study nested in this cohort was conducted to evaluate the link between PGW-related exposures and fathering a child with a birth defect. RESULTS: In the present study, 9% of the 5,666 Gulf veterans who participated reported fertility disorders, and 12% of male veterans reported at least one miscarriage among their partners after the PGW. Overall, 4.2% of fathers reported at least one child with a birth defect conceived after the mission. No PGW-related exposure was associated with any birth defect in children fathered after the PGW mission. Concerning the reported health of children born after the PGW, 1.0% of children presented a pre-term delivery and 2.7% a birth defect. The main birth defects reported were musculoskeletal malformations (0.5%) and urinary system malformations (0.3%). Birth defect incidence in PGWV children conceived after the mission was similar to birth defect incidence described by the Paris Registry of Congenital Malformations, except for Down syndrome (PGWV children incidence was lower than Registry incidence). CONCLUSION: This study did not highlight a high frequency of fertility disorders or miscarriage among French PGW veterans. We found no evidence for a link between paternal exposure during the Gulf War and increased risk of birth defects among French PGWV children.

Advances in medical technology and creation of disparities: the case of Down syndrome.

OBJECTIVES: We assessed socioeconomic differences in probabilities of prenatal diagnoses of Down syndrome and continuation of pregnancies after such diagnoses, along with the effects of these differences on disparities in live-birth prevalences of Down syndrome. METHODS: Using population-based data derived from 1433 cases of Down syndrome and 3731 control births, we assessed age-adjusted effects of maternal occupation and geographic origin on prenatal diagnoses, as well as overall and live-birth odds, of Down syndrome. RESULTS: Maternal occupation and geographic origin had significant effects on the probability of a prenatal diagnosis of Down syndrome and on continuation of pregnancy after such a diagnosis. Women in lower-status occupational categories had higher odds of delivering a live-born infant with Down syndrome. In comparison with women in the highest-status occupational category, the age-adjusted odds ratio for a Down syndrome live birth among women without an occupation was 2.4 (95% confidence interval [CI] = 1.7, 3.3). By contrast, there were no disparities in age-adjusted overall likelihood of Down syndrome. CONCLUSIONS: Socioeconomic differences in use of prenatal testing have created disparities in the live-birth prevalence of Down syndrome. Overall Down syndrome risk does not vary according to socioeconomic status.

Toward the effective surveillance of hypospadias.

Concern about apparent increases in the prevalence of hypospadias--a congenital male reproductive-tract abnormality--in the 1960s to 1980s and the possible connection to increasing exposures to endocrine-disrupting chemicals have underlined the importance of effective surveillance of hypospadias prevalence in the population. We report here the prevalence of hypospadias from 1980 to 1999 in 20 regions of Europe with EUROCAT (European Surveillance of Congenital Anomalies) population-based congenital anomaly registers, 14 of which implemented a guideline to exclude glanular hypospadias. We also report data from the England and Wales National Congenital Anomaly System (NCAS). Our results do not suggest a continuation of rising trends of hypospadias prevalence in Europe. However, a survey of the registers and a special validation study conducted for the years 1994-1996 in nine EUROCAT registers as well as NCAS identified a clear need for a change in the guidelines for registration of hypospadias. We recommend that all hypospadias be included in surveillance, but that information from surgeons be obtained to verify location of the meatus, and whether surgery was performed, in order to interpret trends. Investing resources in repeated special surveys may be more cost-effective than continuous population surveillance. We conclude that it is doubtful whether we have had the systems in place worldwide for the effective surveillance of hypospadias in relation to exposure to potential endocrine-disrupting chemicals.

Preferential associations between oral clefts and other major congenital anomalies.

OBJECTIVES: To identify preferential associations between oral clefts (CL = cleft lip only, CLP = cleft lip with cleft palate, CP = cleft palate) and nonoral cleft anomalies, to interpret them on clinical grounds, and, based on the patterns of associated defects, to establish whether CL and CLP are different conditions. DESIGN AND SETTINGS: Included were 1416 cleft cases (CL = 131, CLP = 565, CP = 720), among 8304 live- and stillborn infants with multiple congenital anomalies, from 6,559,028 births reported to the International Clearinghouse for Birth Defects Surveillance and Research by 15 registries between 1994 and 2004. Rates of associated anomalies were established, and multinomial logistic regressions applied to identify significant associations. RESULTS: Positive associations with clefts were observed for only a few defects, among which anencephaly, encephaloceles, club feet, and ear anomalies were the most outstanding. Anomalies negatively associated with clefts included congenital heart defects, VATER complex (vertebral defects, imperforate anus, tracheoesophageal fistula, and radial and renal dysplasia), and spina bifida. CONCLUSION: The strong association between all types of clefts and anencephaly seems to be attributable to cases with disruptions; the association between CP and club feet seems to be attributable to conditions with fetal akinesia. Some negative associations may depend on methodologic factors, while others, such as clefts with VATER components or clefts with spina bifida, may depend on biological factors. The different patterns of defects associated with CL and CLP, indicating different underlying mechanisms, suggest that CL and CLP reflect more than just variable degrees of severity, and that distinct pathways might be involved.

Prenatal screening and diagnosis of congenital toxoplasmosis: a review of safety issues and psychological consequences for women who undergo screening.

As part of the EUROTOXO initiative, this review focuses on the potential risks associated with prenatal testing for congenital toxoplasmosis. We first review the evidence on the risks of adverse events associated with amniocentesis, which is required for definitive diagnosis of toxoplasmosis infection in the fetus, and for which the most important risk is fetal loss. To date, there has been only one randomized trial to document risks associated with amniocentesis. This trial, which was conducted in 1986, reported a procedure-related rate of fetal loss of 1.0% (95% CI, 0.3-1.5). However, evidence from available controlled studies suggests that the pregnancy loss associated with mid-trimester amniocentesis may be lower. Potential psychological consequences of prenatal testing for congenital toxoplasmosis include parental anxiety due to false positive results and uncertainties related to prognosis of children with a prenatal diagnosis of congenital toxoplasmosis. Parental anxiety may be particularly important in screening strategies that include more frequent screenings, which may in turn entail substantial, and at times unnecessary, anxiety or other negative consequences for women and their families. These negative psychological outcomes should be balanced against the benefits of testing, which can allow women to make an informed choice regarding the pregnancy.

Trends of selected malformations in relation to folic acid recommendations and fortification: an international assessment.

BACKGROUND: Two crucial issues relative to the benefits and impact of folic acid in the prevention of birth defects are whether supplementation recommendations alone, without fortification, are effective in reducing the population-wide rates of neural tube defects (NTDs), and whether such policies can reduce the occurrence of other birth defects. Using data from 15 registries, we assessed rates and trends of 14 major defects, including NTDs, in areas with official recommendations or fortification to assess the effectiveness of recommendations and fortification on a wide range of major birth defects. METHODS: We evaluated surveillance data through 2003 on major birth defects from population-based registries from Europe, North America, and Australia. All included ascertainment of pregnancy terminations (where legal). Trends before and after policies or fortification were assessed via Poisson regression and were compared via rate ratios. RESULTS: Significant changes in trends were seen for NTDs in areas with fortification but not in areas with supplementation recommendations alone. For other major birth defects, there was an overall lack of major trend changes after recommendations or fortification. However, some significant declines were observed for select birth defects in individual areas. CONCLUSIONS: Recommendations alone remain an ineffective approach in translating the known protective effect of folic acid in population-wide decline in NTD rates. Fortification appears to be effective in reducing NTDs. The effect on other birth defects remains unclear.

Trends in prenatal diagnosis, pregnancy termination, and perinatal mortality of newborns with congenital heart disease in France, 1983-2000: a population-based evaluation.

OBJECTIVE: To examine population-based overall and malformation-specific trends in the prenatal diagnosis, pregnancy termination, and perinatal mortality for congenital heart disease (CHD) during a period of rapid progress in prenatal diagnosis and medical management of CHD and to explore the impact of prenatal diagnosis on early neonatal mortality for specific (isolated) cardiac malformations. METHODS: A total of 1982 cases of CHD, which were not associated with a known chromosomal anomaly, were obtained from the Paris Registry of Congenital Malformations. Main outcome measures were trends in the proportions diagnosed and terminated before birth, stillbirth, and early (<1 day, 1-week) neonatal mortality for (1) all cases; (2) all cases excluding isolated ventricular septal defects; and (3) malformation-specific trends for transposition of great arteries, hypoplastic left heart syndrome, coarctation of aorta, and tetralogy of Fallot. Analyses included cusum and binomial regression models for analysis of the trends during 1983-2000. RESULTS: Prenatal diagnosis rates for CHD increased from 23.0% (95% confidence interval [CI]: 19.0-27.4) in 1983-1988 to 47.3% (95% CI: 43.8-50.8) in 1995-2000. Termination rates increased between 1983 and 1989 (9.9%; 95% CI: 7.2-13.2) and 1989 and 1994 (14.7%; 95% CI: 12.3-17.4) but seemed to remain stable thereafter. Other than for hypoplastic left heart syndrome, pregnancy termination was exceptional for the other 3 specific malformations examined. Early neonatal mortality decreased to less than one third in the period 1995-2000 as compared with 1983-1989 (risk ratio, first-week mortality: 0.31; 95% CI: 0.18-0.53). First-week mortality was significantly lower for cases of transposition of great arteries that were diagnosed before birth (risk difference: 15.4%; 95% CI: 4.0-26.7). CONCLUSIONS: Progress in clinical management, together with policies for increased access to prenatal diagnosis, has resulted in both a substantial increase in the prenatal diagnosis and considerable reductions in early neonatal mortality of CHD in the Parisian population.

Sex and congenital malformations: an international perspective.

The study evaluated the sex distribution of major isolated malformations and common trisomies among a large and geographically varied sample. Eighteen registries from 24 countries contributed cases, which were centrally reviewed and classified in three clinical types as isolated, associated, or syndromic. We selected cases of 26 major defects (n = 108,534); trisomy 21, 18, and 13 (n = 30,114); other syndromes (n = 2,898); and multiple congenital anomalies (n = 24,197), for a total of 165,743 cases. We observed a significant deviation of sex distribution (compared to a sex ratio of 1.06 or male proportion of 51.4%) for 24 of the 29 groups (a male excess in 16, a female excess in 8), and in 8 of such groups these estimates varied significantly across registries. A male excess was noted for two left obstructive cardiac defects (hypoplastic left heart and coarctation of the aorta) and a female excess for all the main types of neural tube defects. A male excess was seen for omphalocele but not gastroschisis. For neural tube defects the female excess tended to be stronger in areas with historically high prevalence for these defects. For 15 of the 26 birth defects the sex distribution differed among isolated, associated, and syndromic cases. Some of these epidemiologic commonalities are consistent with known or putative developmental processes. Further, the geographic variation for some defects may reflect local prevalence rates and risk factors. Finally, the findings underscore the need for clinical classification (e.g., into isolated, multiple, syndromes) in studies of birth defects.

International retrospective cohort study of neural tube defects in relation to folic acid recommendations: are the recommendations working?

OBJECTIVES: To evaluate the effectiveness of policies and recommendations on folic acid aimed at reducing the occurrence of neural tube defects. DESIGN: Retrospective cohort study of births monitored by birth defect registries. SETTING: 13 birth defects registries monitoring rates of neural tube defects from 1988 to 1998 in Norway, Finland, Northern Netherlands, England and Wales, Ireland, France (Paris, Strasbourg, and Central East), Hungary, Italy (Emilia Romagna and Campania), Portugal, and Israel. Cases of neural tube defects were ascertained among liveborn infants, stillbirths, and pregnancy terminations (where legal). Policies and recommendations were ascertained by interview and literature review. MAIN OUTCOME MEASURES: Incidences and trends in rates of neural tube defects before and after 1992 (the year of the first recommendations) and before and after the year of local recommendations (when applicable). RESULTS: The issuing of recommendations on folic acid was followed by no detectable improvement in the trends of incidence of neural tube defects. CONCLUSIONS: Recommendations alone did not seem to influence trends in neural tube defects up to six years after the confirmation of the effectiveness of folic acid in clinical trials. New cases of neural tube defects preventable by folic acid continue to accumulate. A reasonable strategy would be to quickly integrate food fortification with fuller implementation of recommendations on supplements.

Effects of maternal age and education on the pattern of prenatal testing: implications for the use of antenatal screening as a solution to the growing number of amniocenteses.

OBJECTIVE: This study was undertaken to assess age-specific effects of maternal education on patterns of prenatal testing. STUDY DESIGN: We used data from a sample of all births in France in 1998. Statistical analysis included logistic regression and likelihood ratio tests. RESULTS: The rate of amniocentesis of women without serum screening was 7.3% for those with 12 years or less, and 16.7% for those with more than 12 years of education. Women with lower levels of education were about 50% more likely to have an amniocentesis if they had serum screening (odds ratio [OR], 1.5; 95% CI, 1.2-1.8). In contrast, women with higher levels of education were less likely to have an amniocentesis with screening (OR, 0.7; 95% CI, 0.6-0.8); the education effect persisted across maternal age groups. CONCLUSION: Many women eligible for reimbursed serum screening, in particular those with higher levels of education, obtain amniocentesis without serum screening. This might limit the use of antenatal screening as a solution to the growing number of amniocenteses.

Socioeconomic barriers to informed decisionmaking regarding maternal serum screening for down syndrome: results of the French National Perinatal Survey of 1998.

OBJECTIVES: We sought to evaluate socioeconomic disparities in serum screening for Down syndrome and assess whether such disparities are more likely to reflect limits in access or information or, rather, informed decisionmaking. METHODS: A nationally representative sample of 12 869 French women completed interviews after giving birth. RESULTS: We found substantial disparities in the likelihood of (1) women not being offered screening, (2) screening not being offered as a result of late prenatal care, and (3) women not knowing whether or not they had undergone screening. Except in the case of nationality, there was essentially no evidence of differences in refusal of testing. CONCLUSIONS: Rather than representing informed decisionmaking, socioeconomic disparities in screening for Down syndrome are mostly due to limits in access or to information.

A population-based evaluation of the impact of antenatal screening for Down's syndrome in France, 1981-2000.

OBJECTIVE: To evaluate the impact of policy and practice changes in prenatal screening for Down's syndrome on prenatal diagnosis and live birth prevalence of Down's syndrome. DESIGN: Population-based observational study. SETTING: Greater Paris. POPULATION: Residents of Greater Paris who gave birth or had a termination of pregnancy in Paris during 1981-2000 (approximately 38,000 births per year). METHODS: Data on 1916 cases of Down's syndrome were obtained from the Paris Registry of Congenital Anomalies. Analyses included binomial and Poisson models of trends in three periods: prior to 1989 (reference period), 1989-1995 (reimbursement of amniocentesis in case of ultrasonographic anomalies) and 1996-2000(widespread use of reimbursed serum screening and measurement of nuchal translucency). MAIN OUTCOME MEASURES: Trends in proportion of Down's syndrome cases diagnosed prior to birth; live birth prevalence of Down's syndrome. RESULTS: The proportion of Down's syndrome detected prenatally for women <38 years of age increased ninefold; from 9.5% (95% CI 2.7-22.6) in 1981 to 84.9% (95% CI 74.6-92.2) in 2000. For women >38 years of age, the increase was 1.5-fold. The live birth prevalence of Down's syndrome decreased by 3% per year (prevalence ratio [PR] 0.97, 95% CI 0.96-0.99); the age-adjusted decrease was 13%. The analysis by period showed that the decrease in live birth prevalence of Down's syndrome was greater after 1988. CONCLUSIONS: By far, most cases of Down's syndrome are currently detected prenatally in the Parisian population. Consequently, the live birth prevalence of Down's syndrome has decreased despite consistent trends towards delayed childbearing. These positive public health effects have to be balanced against a relatively high rate of amniocentesis and the potentially negative consequences of widespread prenatal testing for individuals born with Down's syndrome.

Prenatal diagnostic procedures used in pregnancies with congenital malformations in 14 regions of Europe.

OBJECTIVE: To investigate outcomes of ultrasound investigations (US) and invasive diagnostic procedures in cases of congenital malformations (CM), and to compare the use of invasive prenatal test techniques (amniocentesis (AC) versus chorionic villus sampling (CVS)) among European populations. DESIGN: Analysis of data from population-based registries of CM. SUBJECTS: 25 400 cases of CM recorded by 14 EUROCAT registries covering a total population of 1,013,352 births 1995-99. RESULTS: US were performed in 91% of cases, and positively detected CM in 35% of cases. AC was performed in 24% of the cases and CVS in 3% of cases. Thirty-eight percent of invasive tests gave positive results. Fifty-two percent of cases with maternal age > or = 35 years had an invasive test performed compared to 20% of cases with younger mothers. Considerable variation was found between registries in the uptake rate of invasive tests in cases with older maternal age and on the use of invasive tests with only four regions employing CVS techniques in at least a third of the cases having invasive tests. For chromosomal anomalies US gave positive results in 46% of cases with maternal age < 35 years with US performed and in 36% of cases with maternal age > or = 35 years with US performed. CONCLUSION: Prenatal US was performed in 91% of all pregnancies with CM but the test was only positive in a third of the cases. There was large regional variation in the uptake rate of invasive tests with maternal age of 35 years or more. For every CVS carried out there were nine AC tests. US is an important tool in the prenatal diagnosis of chromosomal anomalies in Europe.

Renal defects and limb deficiencies in 197 infants: is it possible to define the "acrorenal syndrome"?

Dieker and Opitz in 1969 described the simultaneous occurrence of limb deficiencies (LDs) and renal anomalies (RAs) in three patients. Curran and Curran introduced in 1972 the term "acrorenal syndrome." Since then, the term "acrorenal syndrome" is used occasionally, but a well-circumscribed definition has never been established. On the other hand, the concept of an acrorenal polytopic developmental field defect was postulated by Opitz and others to explain the association between RAs and LDs. We undertook this study to investigate whether this acrorenal "syndrome" could be identified in a large group of cases with congenital RAs and a limb deficiency. Eleven birth defect registries that are part of the International Clearinghouse for Birth Defects Monitoring (i.e., registries of ICBDMS in Finland, France [Paris and Strasbourg], Israel, Italy [IPIMC and Emilia Romagna], Mexico, Northern Netherlands, South America, Spain, and the United States [Atlanta]) provided data on 815 infants who had a LD and at least one other major congenital anomaly. These 815 cases were ascertained among 5,163,958 births. We selected the 197 cases who had both a limb deficiency and a renal or urinary tract anomaly. In about 50% of these cases a diagnosis or a recognized phenotype was reported, with chromosomal aberrations and VACTERL being most frequent. In the group with no diagnosis or recognized phenotype (95 cases), we looked for (a) clustering of specific types of LDs and RAs, and (b) for clustering of associated anomalies, in order to find evidence for and be able to define better the term "acrorenal syndrome." Our data suggest that an association exists between LDs and RAs, possibly explained by the concept of the acrorenal polytopic developmental field defect. However, our dataset does not yield evidence for the existence of one distinct "syndrome," defined as a pattern of causally related multiple anomalies. Therefore, use of the term "acrorenal syndrome" should be avoided.

Outcomes of pregnancies diagnosed with Klinefelter syndrome: the possible influence of health professionals.

OBJECTIVE: To describe the association between the outcomes of pregnancies diagnosed with Klinefelter syndrome (KS) and the specialty of the health professional providing pre- and post-diagnostic counselling. METHOD: Data were extracted from the case notes of the 111 cases of KS diagnosed prenatally between 1986 and 1997 in eight geographical regions in five European countries. The data extracted included: outcome of pregnancy, maternal age, social class, parity, gestational age at diagnosis, year of diagnosis and specialties of the health professionals conducting pre- and post-diagnosis consultations. RESULTS: The overall termination rate was 44% (49/111: 95% confidence interval: 35 to 54). Using multivariable logistic regression analysis, the only significant predictor of continuation of the pregnancy was the specialties of the health professionals conducting post-diagnosis counselling: the affected pregnancy was more likely to continue when post-diagnosis counselling involved only a genetics specialist (relative risk: 2.42 (1.14 to 5.92)). CONCLUSION: There is an association between whether or not a woman terminates a pregnancy affected by an unfamiliar fetal anomaly and the professional background of the health professional providing post-diagnostic counselling. The causal nature of this association remains to be determined.