The most common neural tube defects are spina bifida, in which the spin al cord fails to close completely during fetal development, and anencephaly, in which part or all of the brain doesn't develop.

最常见的神经管缺陷是脊柱裂，它是指胎儿期脊髓没有被完全封闭，和无脑畸形，它指部分或全部脑组织没有发育。

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Daily supplementation with folic acid for 1 month prior to conception and during pregnancy may reduce the incidence of neural tube defects such as spina bifida and anencephaly in the child.

在怀孕前一个月及怀孕过程中对叶酸的补充会减低胎儿患神经系统疾病的机率，例如脊柱裂和脑血管畸型。

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The concentrations of the free amino acids in the amniotic fluid of the anencephaly fetus were raised markedly whilst those of the spina bifida fetus were lower than normal.

无脑儿羊水中的氨基酸浓度比正常值明显升高，而脊柱裂羊水中的浓度却比正常值低。

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Researchers at Boston University found evidence that mothers who were overweight before they became pregnant are at greater risk of having a child with neural tube defects, including spina bifida -- which can paralyze legs -- and anencephaly, which results in an underdeveloped brain.

CNN: Study links obesity in pregnancy to birth defects