Neural Tube Defects: The Experience of the Registry of Congenital Malformations of Alsace, France, 1995-2009

Abstract

Context and Objective: Considering the lack of accurate and up-to-date information available about neural tube defects (NTDs) in France, the purpose of this study was to review clinical and epidemiological data of NTDs and to evaluate the current efficiency of prenatal diagnosis in Alsace (northeastern France). Methods: A population-based retrospective study was performed from data of the Registry of Congenital Malformations of Alsace between 1995 and 2009. Data were analyzed as a whole and according to the anatomical type of the malformation (anencephaly, cephalocele and spina bifida). Statistical analyses were carried out using the Statistical Package for the Social Sciences. Results: 272 NTDs were recorded divided in 113 cases of anencephaly (42%), 35 cases of cephalocele (13%) and 124 cases of spina bifida (45%). The total prevalence at birth of 14/10,000 (95% CI 13-16) was stable throughout the reporting period. A chromosome abnormality was identified in 27 cases (12% of all karyotyped cases). NTDs were prenatally diagnosed by ultrasound in 88% of the cases. The mean age upon prenatal diagnosis slightly declined during the 15-year period, significantly for spina bifida only. The global rate of terminations of pregnancy following prenatal diagnosis was 97% (230/238). Conclusion: This work constitutes a unique population-based study providing accurate and specific up-to-date data from a unique center over a longer period (1995-2009). The most important information concerns the high and stable prevalence, which calls into question the efficiency of the primary prevention by folic acid supplementation and the efficiency of prenatal diagnosis.

Diagnostic accuracy of intracranial translucency in detecting spina bifida: a systematic review and meta-analysis

“…3,[27][28][29] Usually, prenatal diagnosis of OSB is carried out by ultrasound examination in the second trimester of pregnancy. 1,2,25,26 Being able to predict OSB earlier has several potential benefits, and failure to detect it may be associated with higher rates of neonatal morbidity and mortality. 30,31 In most countries, parents whose fetus is diagnosed with OSB usually opt for termination of pregnancy.…”

“…The incidence of neural tube defects, including spina bifida (SB), is about 1.4/1000 live births. 1 An ultrasound prenatal diagnosis of SB may be achieved in the second trimester by identifying indirect signs (e.g. the 'lemon sign' and the 'banana sign') as well as by examining the spine in order to visualize the lesion.…”

Triple surveillance: a proposal for an integrated strategy to support and accelerate birth defect prevention

“…Such inability may appear puzzling, as NTDs are clinically obvious and easily and quickly detectable in the newborn nursery or at home without advanced medical training. However, many cases may never make it to birth, either because they result in fetal death (stillbirth) or in elective pregnancy termination after prenatal detection . Thus, tracking NTD occurrence accurately requires including all birth outcomes (live births, stillbirths, and elective terminations of pregnancy for fetal anomalies).…”

“…However, many cases may never make it to birth, either because they result in fetal death (stillbirth) or in elective pregnancy termination after prenatal detection. 13,14 Thus, tracking NTD occurrence accurately requires including all birth outcomes (live births, stillbirths, and elective terminations of pregnancy for fetal anomalies). Programs that miss stillbirths and pregnancy terminations (and are unable to estimate how many they miss) cannot easily interpret their findings: for example, decreasing NTD rates in live births could reflect the successful outcome of primary prevention due to fortification or supplementation campaigns or, in contrast, more cases detected prenatally and terminated-a very different situation.…”

Current views on fetal surgical treatment of myelomeningocele — the Management of Myelomeningocele Study (MOMS) trial and Polish clinical experience

“…Fetal MMC, a serious congenital neural tube defect, is also the most common defect of the central nervous system [1]. The incidence of MMC in the USA has been estimated at 2/10 000 live births, whereas in Poland MMC affects approximately 6/10 000 live births [2,3].…”