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1.
Abnormalities in folate and/or homocysteine metabolism may adversely influence embryonic development, leading to the birth of infants with a variety of congenital malformations, including neural tube defects (NTDs) and craniofacial abnormalities. Based upon suggestive evidence that periconceptional folic acid supplementation is effective in preventing a significant proportion of the aforementioned birth defects, genetic variation in the folate biosynthetic pathways may influence the infant's susceptibility to these birth defects. The goal of our study was to investigate sequence variations in the betaine-homocysteine methyltransferase (BHMT) and betaine-homocysteine methyltransferase (BHMT2) genes as modifiers of risk of spina bifida, cleft palate, and cleft lip and palate. The results of this study indicated that individuals homozygous for the single nucleotide polymorphism R239Q in BHMT did not have elevated risks for spina bifida. Genotype frequencies for the BHMT2 rs626105 polymorphism also did not reveal any elevated risks for spina bifida, and only a modest, imprecise elevation of risk for orofacial clefts. The results of these experiments suggest that variants of the BHMT/BHMT2 genes in infants do not substantially contribute to the risk of spina bifida or orofacial clefts in our study population.  相似文献   

2.
Evidence for the teratogenicity of corticosteroids in humans is limited and has resulted in inconsistent recommendations regarding their use during early pregnancy. We examined the association between women's corticosteroid use during the periconceptional period (1 month before to 3 months after conception) and delivering infants with selected congenital anomalies. Data were derived from a population-based case-control study that included cases of orafacial clefts (n = 662), conotruncal heart defects (n = 207), neural tube defects (n = 265), and limb reduction defects (n = 165). Information on medication use was collected via maternal telephone interviews. Corticosteroid use was associated with an increased risk for isolated cleft lip with or without cleft palate (odds ratio 4.3, 95% confidence interval 1.1–17.2) and isolated cleft palate (odds ratio 5.3, 95% confidence interval 1.1–26.5). Increased risks were not observed for the other anomaly groups studied. These data in conjunction with other epidemiologic data suggest a possible causal association between cleft lip and palate and corticosteroid use. Am. J. Med. Genet. 86:242–244, 1999. © 1999 Wiley-Liss, Inc.  相似文献   

3.
Children with major congenital anomalies often require lifelong access to health and social care services. Estimating future numbers of affected individuals can aid health and social care planning. This study aimed to estimate the number of children aged 0–15 years living with spina bifida or Down syndrome in England and Wales by 2020. Cases of spina bifida and Down syndrome born during 1998–2013 were identified from the Northern Congenital Abnormality Survey and the National Down Syndrome Cytogenetic Register, respectively. The number of infants born with spina bifida during 1998–2019 were estimated by applying the average prevalence rate in the North of England to actual and projected births in England and Wales. Poisson regression was performed to estimate the number of infants born with Down syndrome in England and Wales during 1998–2013 and 2004–2019. The numbers of children aged 0–15 living with spina bifida or Down syndrome in 2014 and in 2020 were then estimated by multiplying year- and age-specific survival estimates by the number of affected births. An estimated 956 children with isolated spina bifida, 623 children with spina bifida and hydrocephalus and 11,592 children with Down syndrome aged 0–15 years will be living in England and Wales by 2020, increases of 7.2%, 12.0% and 12.7% since 2014, respectively. Due to improvements in survival, an increase in population size and changes in maternal age distribution at delivery, we anticipate further increases in the number of children living with spina bifida or Down syndrome by 2020.  相似文献   

4.
Women who consume folic acid in early pregnancy reduced their risks for delivering offspring with neural tube defects (NTDs). The underlying process by which folic acid facilitated this risk reduction is unknown. Investigating genetic variation that influences cellular absorption, transport, and metabolism of folate will help fill this data gap. We focused our studies on a candidate gene that is involved in folate transport, the reduced folate carrier 1 (RFC1). Using data from a California population-based case control interview study (1989-1991 birth cohorts), we investigated whether spina bifida risk was influenced by an interaction between a polymorphism of infant RFC1 at nucleotide 80 (A80G) and maternal periconceptional use of vitamins containing folic acid. Allelic variants of RFC1 were determined by genotyping 133 live-born spina bifida case infants and 188 control infants. The percentages of case infants with the A80/A80, G80/G80, and G80/A80 genotypes were 27.2%, 28.0%, and 44.7%, respectively. The percentages of control infants were similar: 26.1%, 29.3%, and 44.7%. Odds ratios of 1.0 (95% confidence interval 0.5-2.0) for the G80/G80 genotype and 1.1 (0.6-2.0) for the G80/A80 genotype were observed relative to the A80/A80 genotype. Among mothers who did not use vitamins, spina bifida risk was 2.4 (0.8-6.9) for infants with genotype G80/G80 compared to those with A80/A80 genotype. Among mothers who did use vitamins, the risk was 0.5 (0.1-3.1) for infants with the G80/G80 genotype. Although this study did not find an increased spina bifida risk for infants who were heterozygous or homozygous for RFC1 A80G, it did reveal modest evidence for a gene-nutrient interaction between infant homozygosity for the RFC1 G80/G80 genotype and maternal periconceptional intake of vitamins containing folic acid on the risk of spina bifida.  相似文献   

5.
In 2004 the Danish National Board of Health changed its screening recommendations. Since 2005 a first trimester screening for Down syndrome and a prenatal ultrasound screening for congenital anomalies in the second trimester of pregnancy has been offered to all pregnant women.The aim of this study was to describe the prevalence of cleft lip with or without cleft palate and cleft palate in a Danish area and to describe associated anomalies and the development in prenatal diagnosis over time. The study was based on data from the EUROCAT Registry for Funen County. The registry is based on multiple data sources and includes information about live births, fetal deaths with a gestational age >20 weeks and terminations of pregnancy after prenatal diagnosis of severe fetal anomaly. The study included all fetuses/infants out of a population of 182,907 births diagnosed with orofacial clefts born between 1980 and 2014. There were 271 cases diagnosed with cleft lip with or without cleft palate and 127 cases diagnosed with cleft palate, giving a prevalence of 14.8 per 10,000 births for cleft lip with or without cleft palate and 6.9 per 10,000 births for cleft palate. There were no significant changes in prevalence over time for the two anomalies, calculated with and without inclusion of genetic and chromosomal cases. Overall 66 cases were diagnosed prenatally (17% of total). For isolated cleft lip with or without cleft palate none of the 157 cases born before 2005 were diagnosed prenatally compared to 34 of 58 cases (59%) born in 2005–2014 (p?<?0.01). The proportion of liveborn infants with multiple congenital anomalies also changed after 2005 with 15% (39/266) of all liveborn infants with orofacial clefts born 1980–2004 having multiple anomalies compared to 7% (7/96) in 2005–2014 (p?<?0.05).The implementation of the new screening programme in 2005 has given a major change in prenatal detection rate and reduced the proportion of liveborn infants with orofacial clefts classified as multiple congenital anomaly cases. The prevalence of cleft lip with or without cleft palate was higher than reported from many other countries.  相似文献   

6.
Maternal corticosteroid use and risk of selected congenital anomalies.   总被引:3,自引:0,他引:3  
Evidence for the teratogenicity of corticosteroids in humans is limited and has resulted in inconsistent recommendations regarding their use during early pregnancy. We examined the association between women's corticosteroid use during the periconceptional period (1 month before to 3 months after conception) and delivering infants with selected congenital anomalies. Data were derived from a population-based case-control study that included cases of orafacial clefts (n = 662), conotruncal heart defects (n = 207), neural tube defects (n = 265), and limb reduction defects (n = 165). Information on medication use was collected via maternal telephone interviews. Corticosteroid use was associated with an increased risk for isolated cleft lip with or without cleft palate (odds ratio 4.3, 95% confidence interval 1.1-17.2) and isolated cleft palate (odds ratio 5.3, 95% confidence interval 1.1-26.5). Increased risks were not observed for the other anomaly groups studied. These data in conjunction with other epidemiologic data suggest a possible causal association between cleft lip and palate and corticosteroid use.  相似文献   

7.
Cebocephaly and sirenomelia are uncommon birth defects. Their association is extremely rare; however, the presence of spina bifida with both conditions is not unexpected. We report on a female still-birth with cebocephaly, alobar holoprosencephaly, cleft palate, lumbar spina bifida, sirenomelia, a single umbilical artery, and a 46,XX karyotype, but without maternal diabetes mellitus. Our case adds to the examples of overlapping cephalic and caudal defects, possibly related to vulnerability of the midline developmental field or axial mesodermal dysplasia spectrum.  相似文献   

8.

Background

Orofacial clefts occur when the lips or the roof of the mouth do not fuse properly during the early weeks of pregnancy. There is strong evidence that periconceptional use of folic acid can prevent neural tube defects but its effect on oral clefts has generated debate.

Aim

To identify factors associated with suboptimal periconceptional use of folic acid and its potential effect on oral clefts.

Design and setting

The population-based infant cohort of the national Growing Up in Ireland study, which consists of 11 134 9-month-old infants.

Method

Data collection comprised questionnaires conducted by interviewers with parents in parents’ homes. Characteristics of mothers who did or did not take folic acid before and during pregnancy, as well as the effect of folic acid use on the prevalence of cleft lip and palate were recorded.

Results

The prevalence of cleft lip and palate was 1.98 (95% confidence interval [CI] = 1.31 to 2.99) per 1000 9-month-olds. The odds ratio for cleft lip was 4.36-fold higher (95% CI = 1.55 to 12.30, P = 0.005) for infants of mothers who did not take folic acid during the first 3 months of pregnancy, when compared with those who did have a folate intake during the first trimester. Folic acid use was suboptimal in 36.3% (95% CI = 35.4 to 37.2) of the sample.

Conclusion

These findings support the hypothesis that taking folic acid may partially prevent cleft lip and palate. They are particularly relevant for GPs, because they are usually the first port of call for women before and during early pregnancy.  相似文献   

9.
We present data from the Latin American Collaborative Study of Congenital Malformations (ECLAMC) on prevalence rates and etiologic factor associations in neural tube defects. Two series of data are analyzed: the A series, including 740, 139 consecutive infants born in the 1967–1979 period suitable for secular trend analysis and case-control study of risk factors; and the B series, including 255, 834 consecutive stillborn and liveborn infants of the 1980–1982 period suitable for prevalence rate analysis. Anencephaly was registered in 6.0/10,000 births, spina bifida aperta in 6.2/10,000 births, and cephalocele in 2.4/10,000 births. A stable secular trend was observed for the frequency of all three neural tube defect types. Spina bifida was more frequent in Chile than in the rest of South America. No differences in prevalence rates were seen between tropical and non tropical areas. Parental consanguinity and environmental prenatal factors including maternal illnesses, drug intake, and radiation exposure were found in association with anencephaly and spina bifida.  相似文献   

10.
11.
Reports of birth defects rates may focus on defects observed in the newborn period or include defects diagnosed at older ages. However, little information is available on the rates of additional anomalies detected after birth or on the ages at which such anomalies are diagnosed. The aims of this work were to describe the initial diagnoses of oral clefts, isolated or associated with other defects, in newborn infants ascertained in hospitals of the ECLAMC network, and diagnostic changes that occurred due to detection of additional defects during a 1-year follow-up period. Seven hundred ten liveborn infants with cleft lip only (CLO), cleft lip with cleft palate (CLP), or cleft palate (CP) were ascertained between 2003 and 2005. Prevalence estimates of isolated and associated (ASO) clefts, diagnoses in infants with associated clefts, and the percentage of isolated clefts that were reclassified as associated were established. Birth prevalence estimates (per 1,000) were as follows: Total: 1.7; CLP: 0.94 (ASO = 23.5%); CP: 0.46 (ASO = 42.3%); CLO: 0.28 (ASO = 7.6%). Initial diagnoses in infants with associated clefts included 38 infants with chromosomal abnormalities, 33 with non-chromosomal syndromes, 16 with malformation sequences, and 98 with multiple anomalies of unknown etiology. Seven percent of newborns initially classified as isolated were later reclassified as associated. Ten infants without associated defects or clinically suspected syndromes were diagnosed as syndromic only through laboratory findings or family history, illustrating the difference between the terms associated versus isolated, which refers to presence or absence of associated anomalies, and syndromic versus non-syndromic, which refers to etiology.  相似文献   

12.
BACKGROUND: Among mouse genetic mutants that develop neural tube defects (NTDs), some respond to folic acid administration during early pregnancy, whereas NTDs in other mutants are not prevented. This parallels human NTDs, in which up to 30% of cases may be resistant to folic acid. Most spina bifida cases in the folic acid-resistant 'curly tail' mouse can be prevented by treatment with inositol early in embryonic development. Here, the effectiveness and safety during pregnancy of two isomers, myo- and D-chiro-inositol, in preventing mouse NTDs was compared. METHODS AND RESULTS: Inositol was administered either directly to embryos in vitro, or to pregnant females by s.c. or oral routes. Although D-chiro- and myo-inositol both reduced the frequency of spina bifida in curly tail mice by all routes of administration, D-chiro-inositol consistently exhibited the more potent effect, reducing spina bifida by 73-86% in utero compared with a 53-56% reduction with myo-inositol. Pathological analysis revealed no association of either myo- or D-chiro-inositol with reduced litter size or fetal malformation. CONCLUSIONS: D-chiro-inositol offers a safe and effective method for preventing folic acid-resistant NTDs in the curly tail mouse. This raises the possibility of using inositol as an adjunct therapy to folic acid for prevention of NTDs in humans.  相似文献   

13.
Teenage pregnancy and congenital anomalies: which system is vulnerable?   总被引:1,自引:0,他引:1  
BACKGROUND: Teenage pregnancy may be associated with some forms of congenital anomalies. The objective of this study was to identify the types of congenital anomalies associated with teenage pregnancy. METHODS: We carried out a retrospective cohort study of 5 542 861 nulliparous pregnant women younger than 35 years of age with a live singleton birth between 1995 and 2000 in the USA. RESULTS: Compared with adult pregnancy (20-34 years old), and after adjustment for confounding variables, teenage pregnancy (13-19 years old) was associated with increased risk of central nervous system anomalies [odds ratio (OR) 1.08; 95% confidence interval (CI): 1.01, 1.16], gastrointestinal anomalies (OR: 1.39; 95% CI: 1.31, 1.49) and musculoskeletal/integumental anomalies (OR: 1.06; 95% CI: 1.03, 1.10). The teenage pregnancy associated increase in risk for central nervous system anomalies was mainly attributable to anomalies other than anencephalus, spina bifida/meningocele and hydrocephalus and microcephalus; for gastrointestinal anomalies the risk was mainly attributable to omphalocele/gastroschisis; and for musculoskeletal/integumental anomalies the risk was mainly attributable to cleft lip/palate and polydactyly/syndactyly/adactyly. No increased risk was found for circulatory/respiratory anomalies, urogenital anomalies, or Down's syndrome. CONCLUSIONS: Teenage pregnancy increases the risks of congenital anomalies in central nervous, gastrointestinal and musculoskeletal/integumental systems.  相似文献   

14.
OBJECTIVE: To estimate the risk for spina bifida associated with the common mutation C677T of the MTHFR gene in a country with a relatively low prevalence of NTDs. DESIGN: Case-control study. SUBJECTS: Cases: 203 living patients affected with spina bifida (173 myelomeningocele and 30 lipomeningocele); controls: 583 subjects (306 young adults and 277 unselected newborns) from northern and central-southern Italy. SETTING: Cases: three spina bifida centres; young adult controls: DNA banks; newborn controls: regional neonatal screening centres. MAIN OUTCOME MEASURES: Prevalence of the C677T genotypes in cases and controls by place of birth; odds ratios for spina bifida and estimated attributable fraction. RESULTS: The prevalence of T/T, T/C, and C/C genotype was 16.6%, 53.7%, and 29.7% in controls and 25.6%, 43.8%, and 30.6% in cases, respectively. We found no differences between type of defect or place of birth. The odds ratio for spina bifida associated with the T/T genotype v C/C plus T/C was 1.73 (95% CI 1.15, 2.59) and the corresponding attributable fraction was 10.8%. No increased risk was found for heterozygous patients (OR=0.79, 95% CI 0.53-1.18). CONCLUSION: This study, as well as the meta-analysis we updated, shows that homozygosity for the MTHFR C677T mutation is a moderate risk factor in Europe, and even in Italy where there is a relatively low prevalence of spina bifida. The estimated attributable fraction associated with this risk factor explains only a small proportion of cases preventable by periconceptional folic acid supplementation. Thus, other genes involved in folate-homocysteine metabolism, their interaction, and the interaction between genetic and environmental factors should be investigated further.  相似文献   

15.
The necropsy reports of 294 cases of anencephaly and 50 cases of iniencephaly have been examined, and a tubulated list of associated malformations produced. Cases were divided by sex and the presence or absence of spina bifida. Forty-one per cent of the series had other malformations, and other malformations were more common in those cases with spina bifida than in those without. The most frequent single malformations were: hydronephrosis (8%), cleft palate (8%), diaphragmatic hernia (5%), exomphalos (5%), hare lip (4%), and horseshoe kidney (4%). It is suggested that the presence of other malformations in anencephaly or iniencephaly may imply some aetiological heterogeneity.  相似文献   

16.
Hyperthermia is defined as a temperature of at least 1.5 degrees C over the normal core body temperature. It is a proven teratogen in animals and in humans. The type of defects induced by hyperthermia in experimental animals are: anencephaly/exencephaly, encephalocele, microphthalmia, arthrogryposis, abdominal wall defects, limb deficiencies, embryonic death, and resorption. In humans it has been observed that infants prenatally exposed to hyperthermia presented with spina bifida, encephalocele, microphthalmia, micrognathia, external ear anomalies, cardiac defects, hypospadias, gastrointestinal defects, cleft lip and/or cleft palate, abdominal wall defects, diaphragmatic hernia, Hirschsprung disease, M?bius syndrome, oromandibular-limb hypogenesis spectrum, and spontaneous abortions. We describe an additional case with severe limb deficiencies whose mother had fever over 39 degrees C for 2 days in the second and in the fourth month of amenorrhoea. We conclude that, based on the degree of development of the humeri and the femora and the type of limb deficiencies, this case presents a disruption that most probably occurred in the fourth month of gestation.  相似文献   

17.
Adverse pregnancy outcomes may be more frequent among sibs of individuals with neural tube defects (NTDs), and transmission of risk in families with an NTD may be more frequent among maternal relatives. In a study designed to evaluate matrilineal risk for NTDs, we compared adverse pregnancy outcomes among maternal and paternal first cousin pregnancies. Pregnancy histories were obtained by interview with 288 uncles and aunts (parents of the first cousin pregnancies) in 48 Irish NTD families. We analyzed pregnancy outcomes (preterm deliveries, stillbirths, and miscarriages) among 1,033 singleton first cousin pregnancies and compared risk among maternal versus paternal relatives. Maternal first cousin pregnancies were more likely to end adversely when compared to paternal first cousin pregnancies (17.4% vs. 11.7%, P = 0.01). In a logistic regression analysis of pregnancies unaffected by birth defects, maternal line remained independently associated with adverse outcomes (odds ratio (OR) = 1.55, 95% confidence interval (CI) 1.06, 2.27) after controlling for NTD type, maternal age, maternal smoking during pregnancy, first cousin pregnancy's year of birth. The excess risk with maternal line related mainly to spina bifida occulta families (OR = 42.4; CI 2.64, 681; P = 0.008); risk in open spina bifida families was 1.24 (CI 0.82, 1.87; P = 0.3). These results support the hypothesis of excess risk for adverse pregnancy outcomes among maternal relatives in NTD families. Further work is needed, epidemiological as well as clinical and molecular, not only to confirm these findings, but also to define the underlying biological mechanisms linking adverse reproductive outcomes, excess maternal risk and occurrence of NTDs.  相似文献   

18.
Atrioventricular septal defects (AVSDs) have been identified as intriguingly infrequent among Hispanics with Down syndrome (DS) born in the United States. The aim of this study was to evaluate the effect of possible maternal risk factors in the presence of congenital heart defects (CHDs) in Mexican infants with DS. A total of 231 live birth infants born with DS during 2009–2018 at the “Dr. Juan I. Menchaca” Civil Hospital of Guadalajara (Guadalajara, Mexico) were ascertained in a case–control study. Patients with DS with any major CHD were included as cases and those without major CHD as controls. Potential risk factors were analyzed using logistic regression. Of eligible infants with DS, 100 (43.3%) had ≥1 major CHDs (cases) and were compared with a control group of 131 infants (56.7%) with DS without CHDs. Prevalent CHDs were ostium secundum atrial septal defects (ASDs) (46.9%), ventricular septal defects (27.3%), and AVSDs (14%). Lack of folic acid supplementation before pregnancy had a significant risk for CHDs in infants with DS (adjusted odds ratio [aORs] = 2.9 (95% confidence interval [95% CI]: 1.0–8.6) and in the analysis by subtype of CHDs, also, for the occurrence of ASDs (aOR = 11.5, 95% CI: 1.4–94.4). Almost half of the infants with DS in our sample had CHDs, being ASD the commonest subtype and AVSD the rarest. Our ethnic background alone or in concomitance with observed nutritional disadvantages seems to contribute differences in CHD subtype rates in our DS patients.  相似文献   

19.
Tamoxifen is a nonsteroidal antiestrogen used as the current adjuvant endocrine treatment of choice for premenopausal women treated for breast cancer and its potential for causing fetal harm during pregnancy remains inconclusive. While the evidence of tamoxifen's effects on humans in utero is minimal, animal studies have shown evidence of teratogenicity, hence the FDA's class D categorization of the drug. In 1994 Cullins et al. published a case report entitled "Goldenhar's Syndrome Associated with Tamoxifen Given to the Mother During Gestation." At the time of publication, the authors noted that the manufacturer of tamoxifen knew of two cases associated with tamoxifen administration which resulted in congenital craniofacial defects. Cullins' case of Goldenhar syndrome is also a craniofacial disorder and thus represented the third such case. We report on the fourth case of a tamoxifen-associated craniofacial anomaly. The mother became pregnant while undergoing tamoxifen therapy for breast cancer. A child with severe micrognathia and cleft palate was born. It is noteworthy that the two patterns of craniofacial malformations in tamoxifen exposed infants--Goldenhar syndrome in Cullins' et al. case and Pierre Robin sequence reported here--have also both been observed in isotretinoin exposed infants. While a larger spectrum of anomalies is characteristic of retinoic acid embryopathy, the specific craniofacial anomalies include facial asymmetry, microtia, micrognatha and U-shaped cleft of the secondary palate, that is, malformations seen in the two tamoxifen exposed infants. Therefore, it is conceivable that these two agents could produce comparable embryotoxic effects if they function in a like way during embryogenesis. While the majority of tamoxifen exposed infants are normal, the ascertainment of teratogenic effects from tamoxifen will best be determined by data from teratogen registries.  相似文献   

20.
Many infants with anotia or microtia (A/M) have co-occurring birth defects, although few receive syndromic diagnoses in the perinatal period. Evaluation of co-occurring birth defects in children with A/M could identify patterns indicative of undiagnosed/unrecognized syndromes. We obtained information on co-occurring birth defects among infants with A/M for delivery years 1999–2014 from the Texas Birth Defects Registry. We calculated observed-to-expected ratios (OER) to identify birth defect combinations that occurred more often than expected by chance. We excluded children diagnosed with genetic or chromosomal syndromes from analyses. Birth defects and syndromes/associations diagnosed ≤1 year of age were considered. We identified 1310 infants with non-syndromic A/M, of whom 38% (N = 492) were diagnosed with co-occurring major defects. Top combinations included: hydrocephalus, ventricular septal defect, and spinal anomalies (OER 58.4); microphthalmia and anomalies of the aorta (OER 55.4); and cleft lip with or without cleft palate and rib or sternum anomalies (OER 32.8). Some combinations observed in our study may represent undiagnosed/atypical presentations of known A/M associations or syndromes, or novel syndromes yet to be described in the literature. Careful evaluation of infants with multiple birth defects including A/M is warranted to identify individuals with potential genetic or chromosomal syndromes.  相似文献   

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