Male-to-female ratios among NTDs and women's periconceptional intake of folic acid.
Male-to-female ratios among NTDs and women's periconceptional intake of folic acid.
复制标题
NTD 的男女比例和女性围孕期叶酸摄入量。
DOI：
10.1002/bdr2.1708
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发表时间：
2020
影响因子：
2.1
通讯作者：
Finnell,RichardH
中科院分区：
文献类型：
--
作者：
Shaw,GaryM;Yang,Wei;Finnell,RichardH
背景大约十年前，有人提出了一个假说来解释神经管缺陷（NTD）胎儿中女性的优势。该假设预测，女性在妊娠早期摄入较高水平的甲基（例如叶酸）将与受 NTD 影响的新生儿中较小的男女比例差异相关，特别是女性比例较低。我们在四项不同的研究中探讨了这一假设，这些研究调查了人类 NTD，获取了叶酸信息，并通过调查 1998 年美国强制谷物叶酸强化前后收集的数据来利用叶酸强化的时机。方法我们分析了在加利福尼亚州进行的 1987 年至 2011 年出生年份的四项基于人群的病例对照研究的数据。在美国食品供应中叶酸强化之前进行了两项研究。这四项研究中的每一项都包括对怀孕受 NTD 影响的女性（病例）或未怀孕受先天缺陷影响的女性（对照）的访谈。在每项研究中，都引出有关围孕期补充剂使用的信息。我们探讨了每个数据集中的男女比例和 95% 二项式置信限。结果我们对美国强制叶酸强化之前和之后进行的两项病例对照研究进行的分析表明，在前两项研究中，更多受 NTD 影响的胎儿是女性。在强化前进行的研究中，在未补充叶酸的妊娠中，女性的发生率甚至更高。结论我们的研究结果表明，叶酸可以不同程度地降低女性胎儿患 NTD 的风险。
BackgroundAbout a decade ago, a hypothesis was put forward to explain the preponderance of females among neural tube defect (NTD) fetuses. That hypothesis predicts that a woman's higher levels of early gestational intake of methyl groups, such as folic acid, will be associated with lesser male‐to‐female ratio differences in NTD‐affected births, specifically less preponderance of females. We explored this hypothesis in four distinct studies that investigated human NTDs, obtained information on folic acid, and capitalized on timing of folic acid fortification by investigating data that were collected both prior to and after the 1998 initiation of U.S. mandatory folic acid fortification of grains.MethodsWe analyzed data from four population‐based case control studies conducted in California for birth years spanning 1987–2011. Two studies were conducted before folic acid fortification of the U.S. food supply. Each of the four studies included interviews of women who either had NTD‐affected pregnancies (cases) or who did not have a pregnancy affected by a birth defect (controls). In each study, information on periconceptional supplement use was elicited. We explored male‐to‐female ratios and 95% binomial confidence limits in each data set.ResultsOur analyses of two case–control studies performed prior to and two performed post mandatory folate fortification in the United States showed that more NTD‐affected fetuses were female in the first two studies. In the studies done before fortification, the frequency of females was even greater among those pregnancies without folic acid supplementation.ConclusionOur findings suggest folic acid may differentially reduce risk of NTDs among female fetuses.