Detection Of Neural Tube Defects Research Articles

Neural Tube Defect in a Resource Limited Setting: Clinical Profile and Short Term Outcome.

There is a huge burden of neural tube defect (NTD) in Ethiopia, and surgical management is not readily available. We aimed to assess the clinical profile and hospital outcome of children with NTD that were operated in Hawassa University Comprehensive Specialized Hospital, Hawassa, Ethiopia. A retrospective cross-sectional study on 250 children with NTD that were treated in a tertiary hospital from March 2016 to May 2020 was conducted to describe the clinical profile and treatment outcome at discharge. Logistic regression analysis was carried out to evaluate factors that determine mortality. Out of the 250 children, 50.4% were male. Myelomeningocele was the most common type of NTD (77.2%) followed by meningocele (10.4%). Only 3 mothers (1.2%) received periconceptional folic acid. Prenatal diagnosis of NTD was made in only 22 (8.8%) cases. 52.8% of the NTDs were ruptured at presentation and 50.8% had associated sepsis. At presentation, 42.4% were ≤72 hours of age and only 18 neonates (7.2%) were operated within 72 hours of admission. 54% had associated hydrocephalus, 31.6% had Chiari II malformation and 19.6% had club foot. Surgical site infection, post MMC repair hydrocephalus, and meningitis were seen in 8%, 14% and 16.8% of the participants, respectively. The mean duration of hospitalization was 24 ± 14.4 days. Twenty patients (8%) died before discharge from hospital. Prematurity [AOR: 26 (95% CI: 8.01, 86.04), P < 0.001] and the presence of meningitis [AOR: 3.8 (95% CI: 1.12,12.9), P = 0.03]were determinants of mortality. NTDs are substantial health problem in this part of the country. Periconceptional folic acid supplementation is almost non-existent. Prenatal detection of NTDs is very low and management is delayed in the majority of cases. Myelomeningocele is the most common type of NTD. There is high in-hospital mortality, and prematurity and the presence of meningitis are its determinants.

17-Years-Old Teenager with Anencephaly

Background: Anencephaly is the most common type of Neural Tube Defect (NTD). Babies born with anencephaly usually die within hours or a few days after birth. The prevalence of anencephaly cases reaches 5.1 per 10,000 births in the world. There is no therapy for patients with anencephaly, but this condition can be detected early by ultrasonography. Case: 17-year-old girl with abdominal complaints that are getting bigger. She has pregnant and the fetus had suspected anencephaly. The patient’s vital signs were good and laboratory examination showed a slight increase in leukocytes, proteinuria, and leukocyturia. The ultrasound examination results gestational age was 29/30 weeks, and the radiological examination by a radiologist expert had similar results. The baby girl was born with a weight of 1,568 grams and an Apgar score of 2-3. On examination, prominent brain tissue was visible. The baby was treated for three days at Trenggalek General Hospital and survived for four days. Conclusion: The aetiology and pathophysiology of anencephaly are still unclear, but risk factors such as environmental, genetic, maternal and fetal conditions encourage this condition. Detection of NTDs can be done early in pregnancy using ultrasound. Early prevention must be carried out, such as regular consumption of folic acid to prevent the occurrence of NTDs. In this case, the occurrence of NTDs is thought to be due to the condition of the mother who is too young, socioeconomic factors, low consumption of folic acid and lack of knowledge and information about the importance of prevention in NTD cases.

EARLY OUTCOME ANALYSIS OF NEURAL TUBE DEFECTS PRESENTING IN NEONATAL PERIOD: OUR EXPERIENCE

Background: Neural tube defects (NTDs) are congenital malformation resulting from failure of complete or partial closure of the neural tube in developing embryo. Aims and Objectives: The aim of this study is to present our experience, management and early outcomes (one month post-operatively) of neural tube defects presenting in neonatal period at our high volume tertiary care teaching Institutions. Materials and methods: This retrospective cohort study was conducted over a period of 10 years from January 2007 to December 2016. Medical records of neonates treated for neural tube defects were recorded in a pre-designed Performa. Results: A total of 286 patients with clinically diagnosed neural tube defects presenting in the neonatal period were studied. Male: female ratio was 1.11. The mean birth weight was 2350g. History of peri-conceptional use of folic acid was found in 15 (5.24%) mothers. One hundred seventeen (40.90%) of the patients had multiple system involvement. Most common was orthopedic deformities. Associated hydrocephalus was appreciated in 259 (90.56%) patients. Meningomyelocele was the most common anomaly seen in 239 (83.57%), 24 (8.39%) as meningocele and 23 (8.04%) were diagnosed as having Encephalocele. Surgery with decapping and repair was performed in 277 (96.85%) of the patients. Ventriculoperitoneal (VP) shunt operation before repair of meningomyelocele was performed in 9 (3.15%) patients, while in 19 (6.64%) patients, VP shunt operation was performed after the repair of NTD's in the early (one month) postoperative period. Clinical sepsis developed in the postoperative period in twenty one (7.58%) out of 277 patients, for which antibiotics were stepped up. Thirteen patients (4.69%) died postoperatively due to sepsis and associated anomalies. Conclusions: We present our retrospective report on neural tube defects from Indian subcontinent with accurate baseline data. Meningomyelocele was the most common type of NTD's. We recommend that folic acid supplementation should begin before marriage to raise its serum levels before the conception. Antenatal care especially antenatal ultrasonography must be contemplated as early as possible in early detection of NTDs.

Detection of spina bifida in the first trimester of gestation in association with triploidy

The case of prenatal detection of spina bifida at 12+3 weeks of gestation is described. Termination of pregnancy was performed at 13+3 weeks. Post-abortion karyotyping revealed triploidy (69XXX). Diagnostic tools for early detection of neural tube defects in the 1st trimester of gestation and subsequent appropriate management of pregnancy are discussed.

Normative Values of Intracranial Translucency (IT) Thickness as an Ultrasonographic Marker for Neural Tube Defect (NTD) Screening in the Iranian Singleton Pregnancies

Background: Neural tube defects are the second most common congenital anomalies following congenital heart defects. Once NTD is detected prenatally, different options are available including pregnancy termination, and intrauterine fetal surgery. Considering these facts, prenatal screening for NTDs is becoming a part of routine fetal care. Several ultrasonographic markers have been suggested for detection of NTD during pregnancy. Intracranial translucency (IT) is a relatively new ultrasonographic marker for NTD screening during first-trimester. It actually represents the fourth cerebral ventricle, seen as an anechoic structure in the mid-sagittal plane of the fetal face posterior to the brainstem. Its absence or obliteration can be an indirect sign of open spina bifida, which is caused secondary to the caudal displacement of brain in these fetuses. In this study, we aimed to determine the normative values of this marker in the Iranian population. Objectives: To determine the normative values of intracranial translucency (IT) thickness in the Iranian singleton pregnancies. Methods: 230 consecutive singleton pregnancies between 11 weeks and 13 weeks+6 days of gestation were included in the study during 9 months (June 2015 to February 2016) prospectively in Mahdieh and Sarem womens hospital, Tehran, Iran. Crown-rump length (CRL), nuchal translucency (NT) thickness, fetal heart rate, and nasal bone status were evaluated by ultrasound as parts of the routine first-trimester screening for aneuploidies. Precise gestational age was determined by the fetal CRL as well. In addition, IT thickness was measured in the mid-sagittal view of the fetal head between two echogenic horizontal lines: posterior border of the brainstem anteriorly and anterior aspect of the fourth ventricle choroid plexus posteriorly (figure 1). All the measurements were performed by a radiologist with four years of experience in fetal imaging. Ethnicities other than Iranian, multiple gestation pregnancies, and pregnancies conceived by assisted reproductive technology (ART) were not included in the study initially. Other exclusion criteria were any obvious anatomic fetal anomaly in the ultrasound examination, abnormal genetic or maternal serum biomarker test result, increased NT, and presence of open NTD in the post-partum follow-up. Results: : Of the 230 included singleton pregnancies, all of them resulted in healthy live births, except for two pregnancies terminated at 19 and 17 weeks of gestation due to severe skeletal dysplasia and an abnormal genetic test result compatible with Down syndrome, respectively. None of born babies had open NTD on post-partum follow-up. Five pregnancies were excluded from the final analysis, including a fetus with increased NT, two pregnancies with abnormal maternal serum biomarker test result (one of which confirmed to be trisomy 21), poor visualization due to maternal severe obesity in one case, and skeletal dysplasia diagnosed at 19 weeks of gestation in one of pregnancies. The median maternal age was 29 (range, 16 - 49) years. Median gestational age was 12 weeks + 5 days (range, 11 weeks + 2 days-13 weeks + 6 days). There were 68 cases per gestational week between 11 and 11 + 6 weeks, 84 cases between 12 and 12 + 6 weeks, and 73 cases between 13 and 13 + 6 weeks. Mean IT thickness was 1.94 - 0.73 mm (95% CI, 1.84 - 2.04) in all included pregnancies. This measurement was 1.57 - 0.34 mm (95% CI, 1.49 - 1.65) for fetuses between 11 and 11 + 6 weeks, 1.86 - 0.29 mm (95% CI, 1.80 - 1.92) for fetuses between 12 and 12 + 6 weeks, and 2.12 - 0.41 mm (95% CI, 2.02 - 2.22) for fetuses between 13 and 13 + 6 weeks. Kolmogorov-Smirnov analysis demonstrated normality of IT thickness distribution in the included cases (P > 0.10). Linear regression analysis demonstrated that there was a statistically significant positive linear association between IT thickness and gestational age (rs = 0.92, P = 0.021). Conclusions: We determined the normative values of IT thickness for the Iranian fetuses in a pilot study, which may be considered for NTD screening during the first-trimester in the national and international guidelines. It is important to determine normal measurements of different ultrasonographic and biochemistry markers nationally, since there are significant differences among various ethnicities. One should expect that IT thickness increases in a linear manner during first-trimester, and in case of its obliteration or absence open NTDs should be strongly suspected.

P30.05: Prenatal detection of neural tube defects in the Netherlands: timing of diagnosis and pregnancy outcome

P30.05: Prenatal detection of neural tube defects in the Netherlands: timing of diagnosis and pregnancy outcome

Estudio preliminar sobre detección de defectos de tubo neural mediante ultrasonido.

Estudio restrospectivo realizado en el Hospital Nacional Cayetano Heredia, entre enero de 1991 y abril de 1993 en 972 productos evaluados mediante ultrasonido . El objetivo fue conocer la precisión de la ecografía de nivel I realizada a partir del segundo trimestre de gestación, en la detección de defectos del tubo neural en la población general. Para ello se correlacionan los hallazgos ecográficos con los de la evaluación clínica del recién nacido. Se halló una tasa de detección de defectos de tubo neural de 90% (96/100), especificidad de 99,6% (958/964) tasa de falsos positivos de 30% (4113) y tasa de falsos negativos de 0,1% ( 1959) . Se detectó el 100% de las anencefalias. El ultrasonido es un procedimiento diagnóstico de gran utilidad para la detección de defectos de tubo neural.

Differentiation of early first‐trimester cranial neural tube defects

Neural tube defects (NTDs) are one of the most commonly reported birth defects and are the result of failure of primary neurulation, the folding and fusion of the neural plate1. We report on three early first-trimester cases with different types of cranial neural tube defects (NTD) not previously reported in ultrasound studies. Previously, it was believed that the process of neural tube closure occurred in a ‘zipper-like’ fashion, starting at one point and proceeding in both cranial and caudal directions. However, neural tube closure is a more complex process. More recently, Nakatsu et al. described three different closure initiation sites of the human neural tube after studying miscarried embryos2. Following from this closure model six different types of cranial NTDs were distinguished, based on location of the closure defect (Figure S1)2. Survival rates significantly decreased if the rhombencephalon, or fourth ventricle, was involved in the defect (Types III, IV and V) with two-thirds of cases failing to survive beyond 7 weeks' gestational age. Embryos with total dysraphism (Type VI) failed to survive at an even earlier stage. However, 70% of the embryos with a rostral defect (Types I and II) did survive beyond 7 weeks. In Case 1 (crown–rump length (CRL), 23 mm) and Case 2 (CRL, 13 mm) a cranial defect was seen from the mesencephalon to the rhombencephalon, suggestive of Type IV (Figure 1 and Figure S2). In Case 3 (CRL, 14 mm) the neural tube did not close at the parietal region of the head and most likely represents a Type II cranial NTD (Figure 2). We concluded that some of the different types of cranial NTDs can be diagnosed in vivo using high-frequency two- and three-dimensional transvaginal ultrasound during the early first trimester of pregnancy. Increasing awareness of the existence of different types of cranial NTDs is important in beginning to unravel the etiology of the development of NTDs. If good documentation exists the different types of cranial NTDs might be linked to different genetic pathways or environmental factors3. However, since the moment of demise in the majority of cases appears to be before 10 weeks' gestation, detection remains a challenge. The existence of different types of cranial NTDs is a rather recent insight and the implications for counseling are not yet well understood. Understanding the cause of these malformations might contribute to determination of increased risks in couples and development of new prevention strategies. The in vivo detection of cranial NTDs raises the question whether these women are at increased risk for recurrence of NTD. If so, in a subsequent pregnancy, an increased dosage of supplemental folic acid is indicated and additional ultrasound examinations are recommended. In conclusion, different types of cranial NTDs can be diagnosed using transvaginal ultrasound examination in early pregnancy. Detection of these NTDs is of particular importance in beginning to understand etiology, in developing prevention strategies, in counseling patients and in initiating new research projects. This research was financially supported by Erasmus Trustfonds, Erasmus MC Vriendenfonds, Meindert de Hoop Foundation and Fonds NutsOhra. L. Baken*†, N. Exalto†, B. Benoit‡, P. J. van der Spek§, E. A. P. Steegers† and I. A. L. Groenenberg† †Department of Obstetrics and Gynaecology, Division of Obstetrics and Prenatal Medicine, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, The Netherlands; ‡Department of Obstetrics and Gynecology, Princess Grace Hospital, Monaco; §Department of Bioinformatics, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, The Netherlands *Correspondence. (e-mail: l.baken@erasmusmc.nl) Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Amniotic fluid and serum biomarkers from women with neural tube defect–affected pregnancies: a case study for myelomeningocele and anencephaly

Object The authors sought to identify novel biomarkers for early detection of neural tube defects (NTDs) in human fetuses. Methods Amniotic fluid and serum were drawn from women in the second trimester of pregnancy. The study group included 2 women pregnant with normal fetuses and 4 with fetuses displaying myelomeningocele (n = 1), anencephaly (n = 1), holoprosencephaly (n = 1), or encephalocele (n = 1). Amniotic fluid stem cells (AFSCs) were isolated and cultured. The cells were immunostained for the stem cell markers Oct4, CD133, and Sox2; the epigenetic biomarkers H3K4me2, H3K4me3, H3K27me2, H3K27me3, H3K9Ac, and H3K18Ac; and the histone modifiers KDM6B (a histone H3K27 demethylase) and Gcn5 (a histone acetyltransferase). The levels of 2 markers for neural tube development, bone morphogenetic protein–4 (BMP4) and sonic hedgehog (Shh), were measured in amniotic fluid and serum using an enzyme-linked immunosorbent assay. Results The AFSCs from the woman pregnant with a fetus affected by myelomeningocele had higher levels of H3K4me2, H3K4me3, H3K27me2, and H3K27me3 and lower levels of KDM6B than the AFSCs from the women with healthy fetuses. The levels of H3K9ac, H3K18ac, and Gcn5 were also decreased in the woman with the fetus exhibiting myelomeningocele. In AFSCs from the woman carrying an anencephalic fetus, levels of H3K27me3, along with those of H3K9Ac, H3K18ac, and Gcn5, were increased, while that of KDM6B was decreased. Compared with the normal controls, the levels of BMP4 in amniotic fluid and serum from the woman with a fetus with myelomeningocele were increased, whereas levels of Shh were increased in the woman pregnant with a fetus displaying anencephaly. Conclusions The levels of epigenetic marks, such as H3K4me, H3K27me3, H3K9Ac, and H3K18A, in cultured AFSCs in combination with levels of key developmental proteins, such as BMP4 and Shh, are potential biomarkers for early detection and identification of NTDs in amniotic fluid and maternal serum.

Appeal to the European Food Safety Authority

About 4500 neural tube defects (NTD) occur every year in the European Union. Children with NTD will suffer from a lifelong disability often with inability to walk, hydrocephalus, learning problems, urinary infections and genital dysfunction. Up to two-thirds of these tragic cases can be prevented by folic acid supplementation. USA and Canada implemented mandatory folic acid fortification of wheat flour and corn in 1998. A number of other countries followed the North American rules including Australia, most states in South America and many countries in the Middle East and Africa. In China and India, it is voluntary. EU is an exception, although the UK is considering fortification. I feel particularly ashamed of my own country Sweden, where food is not even voluntarily fortified with folic acid. Thus, many children could be saved from being severely disabled, and several more foetuses would not be aborted owing to the detection of NTD by ultrasound. The cleft palate could also, to some extent, be prevented. In this issue of the Acta Paediatrica, Margaretha Jägerstad, professor emerita of food sciences, reviews the argument in favour of and against folic acid fortification. She reports that the daily folate intake among women is lower than the recommended levels. By fortification, most women will reach the recommended intake of folate (about 400 μg/day). With these levels there is no increased risk for cancer, which has been the strongest argument against fortification in the EU countries. Actually, it decreases the cancer risk, as the risk for cancer seems to be related in U-shaped fashion to folate concentrations. Only if a man eats more than five loaves of bread made of fortified flour every day, he may reach levels of folic acid that have been demonstrated to increase the risk of cancer in rats. The European Food Safety Authority (EFSA) is still hesitant to recommend fortification with folic acid and requires more investigations. However, neither EFSA nor the global World Cancer review present data on increased cancer risk at physiological folate intake. Therefore, EU should act to implement folic acid fortification as NTD prophylaxis as soon as possible. I am convinced that the EU Commission would act promptly if a preventable error was detected in the Airbus plane or European cars, which would cause thousands of deaths and/or severe handicaps every year.

Evolution of prenatal detection of neural tube defects in the pregnant population of the city of Barcelona from 1992 to 2006

To assess the prenatal ultrasound detection rates (DR) of neural tube defects (NTDs) and its evolution over the 1992 to 2006 period in the pregnant population of the city of Barcelona. Data on the population-based register of birth defects were used to assess the evolution of the prenatal DR for isolated NTD, including anencephaly, spina bifida and encephalocele by trimester of gestation. In the register, 127 isolated NTD cases, including 71 anencephalic fetuses, 49 spina bifidas and 7 encephaloceles were noted. Overall, prenatal ultrasound DR for isolated NTD was 94%. All fetuses with anencephaly or encephalocele were prenatally detected (100% DR), whereas DR for spina bifida was 84%, with no apparent variation over the observation period. An important increase in first trimester DRs was observed for anencephaly, rising from 16% in the first years of the study (1992-1996) to 71% in the last years (2002-2006). A high DR (94%) for isolated NTD was observed in the city of Barcelona. The single significant change across the study period was an increase in the first trimester DR for anencephaly (from 16% to 71%).

Partial monosomy 13q (13q21.32→qter) and partial trisomy 8p (8p12→pter) presenting with anencephaly and increased nuchal translucency: array comparative genomic hybridization characterization

Objective To present array comparative genomic hybridization (aCGH) characterization of partial monosomy 13q (13q21.32→qter) and partial trisomy 8p (8p12→pter) presenting with anencephaly and increased nuchal translucency (NT). Case Report A 34-year-old primigravid woman was referred to the hospital at 12 weeks of gestation for termination of the pregnancy because of major structural abnormalities of the fetus. Prenatal ultrasound revealed a malformed fetus with anencephaly and an increased NT thickness of 5 mm at 12 weeks of gestation. Cytogenetic analysis of the fetus revealed a derivative chromosome 13. The mother was subsequently found to carry a balanced reciprocal translocation between 8p12 and 13q21. Bacterial artificial chromosome-based aCGH using fetal DNA demonstrated partial trisomy 8p and partial monosomy 13q [arr cgh 8p23.3p12 (RP11-1150M5→RP11-1145H12)×3, 13q21.32q34 (RP11-326B4→RP11-450H16)×1]. Oligonucleotide-based aCGH showed a 36.7-Mb duplication of distal 8p and a 48.4-Mb deletion of distal 13q. The fetal karyotype was 46,XY,der(13) t(8;13)(p12;q21.32)mat. The maternal karyotype was 46,XX,t(8;13)(p12;q21.32). Conclusion The 13q deletion syndrome can be associated with neural tube defects and increased NT in the first trimester. Prenatal sonographic detection of neural tube defects should alert chromosomal abnormalities and prompt cytogenetic investigation, which may lead to the identification of an unexpected parental translocation involving chromosomal segments associated with neural tube development.

Fetal valproate syndrome in a 2-month-old male infant

Fetal valproate syndrome (FVS) results from prenatal exposure to valproic acid. It is characterized by a distinctive facial appearance, a cluster of minor and major anomalies and central nervous system dysfunction. We describe a 2-month-old male infant with the typical dysmorphic features characteristic of FVS. He had a persistent left superior vena cava draining into a dilated coronary sinus and mild pulmonary hypertension. There was a history of maternal intake of sodium valproate during pregnancy.

Alpha-Fetoprotein Detection of Neural Tube Defects and the Impact of Standard Ultra sound

Obstetric Anesthesia Digest: September 2007 - Volume 27 - Issue 3 - p 142-143 doi: 10.1097/01.aoa.0000288275.58919.b1

Fetal Alert Network: Surveying congenital anomalies

Fetal Alert Network: Surveying congenital anomalies

Fetal anomaly scan potentially will replace routine AFAFP assays for the detection of neural tube defects

Introduction of the second-trimester fetal anomaly scan and the decision to offer this scan to every woman in the 18th-22nd week of pregnancy necessitates a re-evaluation of the diagnostic value of the measurement of alpha-fetoprotein (AFP) concentrations in the amniotic fluid (AF) for the detection of neural tube defects (NTDs). In this study of 6501 women who underwent amniocentesis, amniotic fluid AFP (AFAFP) concentrations were measured. The women were divided into three categories: group I, without any increased risk of fetal NTD (N = 6188); group II, with an increased risk of fetal NTD (N = 258); and group III, with a clinically diagnosed fetal NTD with known AFAFP concentrations (N = 55). In 27 women of group I (0.4%), the MoM (multiple of the median) level was > 2.5 times the median AFP concentration for the corresponding gestational age, and in two fetuses this was related to NTD. In two pregnancies of group II (0.8%), an increased AFAFP was related to NTD. In group III, 44 of the 55 (80%) samples had an increased AFAFP. In the near future, it is likely that imaging will replace AFAFP assays for the detection of fetal NTDs because high quality ultrasound imaging will detect NTDs accurately.

Alpha-fetoprotein detection of neural tube defects and the impact of standard ultrasound

The purpose of this study was to evaluate neural tube defect (NTD) detection according to whether serum alpha-fetoprotein (AFP) screening or standard ultrasound are performed. Prenatal and neonatal datasets were reviewed to identify pregnancies with NTDs from 1 institution between January 2000 and December 2003. AFP screening was offered < 21 weeks and considered elevated if > or = 2.50 multiples of the median. Standard ultrasound was performed for specific indications in low-risk pregnancies. There were 66 NTDs, 1 per 950 deliveries. AFP sensitivity was 65%. If the gestational age used for AFP calculation was confirmed with ultrasound, sensitivity improved to 86%. The sensitivity of standard ultrasound was 100%, P < .001 compared with AFP screening. NTDs detected with standard ultrasound were identified later in gestation, as examinations were performed for other indications. Standard ultrasound improved NTD detection over AFP screening alone, by improving AFP test sensitivity and identifying NTDs in low-risk pregnancies.

P14.70: Routine assessment of amniotic fluid alpha‐fetoprotein in second trimester genetic amniocentesis to detect fetal neural tube defects

The main aim of the study was to evaluate the clinical usefulness of routine assessment of amniotic fluid alpha-fetoprotein (AF-AFP) in second trimester genetic amniocentesis, to detect fetal neural tube defects (NTD). A secondary aim was to survey the routine for analyses of AF-AFP in obstetric clinics in Sweden today. This is a retrospective study. The studied population included all 1919 pregnant women, from the county hospitals of Norrköping and Jönköping, who underwent second trimester genetic amniocentesis, during the years 1993–2003. Indications for the genetic amniocentesis were elevated maternal age (> 35 years old) or increased anxiety for chromosomal defects of the expected baby. A questionnaire concerning policy and experience of AF-AFP analyses was sent to all obstetric clinics in Sweden who performed genetic amniocentesis in 2003. Of the 1811 analysis of AF-AFP, eight cases had increased values (0.4%) and five of them were false positive (63%). Of the three true positive cases, one had clinical relevance. In the other two cases the detection of NTD was of subordinate importance; one fetus had trisomy 18 and the other pregnancy was a missed abortion at the ultrasound check-up. In Sweden 91% (39/43) of the obstetric clinics perform routine assessment of AF-AFP at second trimester genetic amniocentesis, but according to the answers in the questionnaire only 8% of the clinics regarded the analyses useful in clinical practice. During 2003 about 8000 genetic amniocentesis were made in Sweden. We concluded that routine assessment of AF-AFP in second trimester genetic amniocentesis does not appear to be justified. The clinical usefulness seems to be limited, and the result of AF-AFP more often creates parental anxiety.

Why women say yes to prenatal diagnosis

Despite considerable concern of bioethicists, disabilities rights activists, feminists and others about the spread of prenatal diagnostic technologies, their routine acceptance in many parts of the world continues at a rapid pace. Yet, there is wide variation by country and region in rates of acceptance of prenatal diagnosis. We draw on John McKinlay's model of how a medical innovation becomes routinized to explore the circumstances that led to the widespread use of one prenatal diagnostic screen—the maternal serum alpha fetoprotein (MSAFP) test for the detection of neural tube defects and other developmental disabilities. As predicted by McKinlay's model, analysis of published data suggests that strong institutional or provider support is the best predictor of women's level of MSAFP test acceptance. Data collected at a health maintenance organization in California illuminate the processes through which medico-legal and institutional forces affect the use of MSAFP screening. By examining the language women use to talk about MSAFP screening, we show how providers also shape women's understandings of the meaning and purpose of MSAFP screening. These data ultimately shed light on how the very ethical issues which concern critics of prenatal diagnosis become obscured in the processes by which this screening test becomes accepted as routine.

First trimester sonographic detection of neural tube defect in a high-risk population

First trimester sonographic detection of neural tube defect in a high-risk population