我们最新的研究显示，在怀孕期间食用鱼肉并不会增加您的孩子罹患自闭症的风险。事实上，研究表明鱼类可能对神经系统的发育健康有益。
A possible link between mercury exposure and autism has been the subject of much debate over the years. In pregnancy, mercury travels in the mother's blood through the placenta and into the foetus, where it acts as a toxin, affecting the development of the foetal nervous system.
汞与自闭症之间可能存在的联系多年来一直是争论不休的话题。在怀孕期间，汞可以通过母亲的血液渗入到胎盘中，进入胎儿循环系统，因其毒性影响到胎儿神经系统的发育。
This has resulted in concern over two particular sources of mercury. First, fish is a source of mercury in the diet and there is concern that high fish consumption may cause damage to the developing nervous system.
这引发了人们对摄入汞的渠道来源的关注。首先，鱼是通常食物中汞元素的主要来源，人们担心大量食用鱼肉可能会对发育中的神经系统造成损害。
There is increasing evidence, however, that the beneficial effects of eating fish, probably through the nutrients it provides, outweigh the negative effects of the mercury it contains, even in people who eat a great deal of fish, such as the inhabitants of the Seychelles.
这引发了人们对摄入汞的渠道来源的关注。首先，鱼是通常食物中汞元素的主要来源，人们担心大量食用鱼肉可能会对发育中的神经系统造成损害。
Second, the use of thiomersal, a mercury-based preservative that is used in some vaccines, has created fears in some that immunisations might cause harm.
这引发了人们对摄入汞的渠道来源的关注。首先，鱼是通常食物中汞元素的主要来源，人们担心大量食用鱼肉可能会对发育中的神经系统造成损害。
Specifically, some people fear that vaccines containing thiomersal might be a cause of autism.
具体点说，有些人担心含有硫柳汞的疫苗可能是导致自闭症的原因。
Reviews of studies on this have reduced the concern over vaccines, and, in the EU at least, thiomersal is no longer used in childhood vaccinations.
对此问题的争论甚至超过了公众对疫苗本身的关注，并且至少在欧盟，硫柳汞不再用做儿童疫苗的防腐剂。
What's more, the amount of mercury in thiomersal is very small compared with the amount absorbed from the atmosphere and from the diet. Still, the fear that mercury is linked to autism persists.
更重要的是，硫柳汞中的汞含量比大气和饮食中的所含有的汞元素还要少。不过，始终难以消去“汞引发自闭症”这样的疑虑。
Worse off without fish
不接种疫苗，如果还不吃鱼的话，事情就变得更糟了。
With these concerns in mind, we have carried out a study to look at the link between mercury levels and fish consumption in pregnant women, together with autistic traits and diagnosed autism in their children, up to the age of nine years.
考虑到这些问题，我们开展了一项研究，希望确认孕妇血液中汞水平和鱼类消费量之间的关系，以及这两者与9岁之前呈现出自闭症特征和经过确诊为自闭症的儿童之间的关系。
The data were collected as part of the Children of the 90s Study (Avon Longitudinal Study of Parents and Children), which is based in Bristol, England.
原始数据是作为90年代一项儿童研究(父母和儿童的方差分析纵向研究)的一部分被收集起来的。对象来自英国的布里斯托尔。
We found that, although the mother's blood mercury level was higher if she ate more fish, there was no evidence that having a higher level of mercury meant that her child was more likely to be autistic or have autistic traits.
我们发现，如果母亲吃了很多的鱼，那么尽管她的血液汞含量比较高，也没有证据表明她的孩子以后更可能罹患自闭症或确实患有了自闭症。
In fact, the score for one particular autistic trait, social cognition (for example, not being aware of other people's feelings), was likely to be worse in the child if the mother had not eaten fish in pregnancy.
事实上，如果母亲在怀孕期间拒绝吃鱼，那么某项单一自闭症特征——社会认知缺失(例如，不知道其他人的感受)程度反而会加剧。
Clearer guidelines
明确的指导意见
National guidelines in the UK, and in many other countries, recommend that pregnant women eat at least two portions of fish per week, with one of them being an oily fish.
英国和其他许多国家的卫生指南建议孕妇每周至少食用两次鱼肉，其中至少有一条是富含脂肪的鱼。
Our study, and other people's studies, back this recommendation. As we have previously argued this recommendation needs to be made more prominent, and the guidelines need to be made clearer and simpler.
我们的研究和其他人的研究均支持这一建议。正如我们以前所说的，最好把这项建议用黑体加粗，贴在准妈妈的床头。
Caroline Taylor, Research Fellow, University of Bristol.
作者 Caroline Taylor，布里斯托大学研究员。
