2016年美國大選可能改變了加拿大的出生性別比

2016年美國大選可能改變了加拿大的出生性別比

The 2016 election had some unexpected effects in surprising places. Rising to the top of that list is the possibility of a reduced number of boys born in parts of Canada.

2016年大選在一些出人意料的地方產生了一些意想不到的影響。排在首位的是在加拿大部分地區(qū)出生的男孩數(shù)量減少的可能性。

Disastrous events such as wars or famines can alter the proportion of male and female babies born in the years thereafter. The shift is small but can easily be detected when millions of births are involved, such as during both world wars. Even events that do not affect mothers directly can have an impact – fewer boys than normal were born in the USA shortly after 9/11, or in Norway after the 2011 far right massacre.

災難性的事件，如戰(zhàn)爭或饑荒，會改變此后幾年出生的男嬰和女嬰的比例。這種變化很小，但當涉及到數(shù)百萬人的出生時，比如在兩次世界大戰(zhàn)期間，就很容易發(fā)現(xiàn)。即使是不直接影響母親的事件也會產生影響——9/11事件后不久，美國出生的男孩數(shù)量低于正常水平，或者2011年極右翼大屠殺后，挪威出生的男孩數(shù)量低于正常水平。

Stephen Luntz

Dr Ravi Retnakaran and Dr Chang Ye of Mount Sinai Hospital, Toronto, wondered if election results could do the same thing. Naturally, this would be harder to detect – a whole nation is traumatized by terrorism, but elections make about as many people happy as sad.

多倫多西奈山醫(yī)院的Ravi Retnakaran博士和Chang Ye博士想知道選舉結果是否也能起到同樣的作用。當然，這很難察覺——整個國家都受到了恐怖主義的創(chuàng)傷，但選舉讓同樣多的人感到高興，也讓同樣多的人感到悲傷。

On the other hand, other countries are sometimes fairly united in who they want to win their neighbors' elections. American elections transfix the world, and polling companies sometimes ask the voters of other nations who they would vote for if they could. Canadians consistently indicate an overwhelming preference for Democrats over Republicans, including at the 2016 presidential election. Consequently, Retnakaran and Ye looked at the numbers of boys and girls born in Ontario before and after the election.

另一方面，其他國家有時在他們希望誰贏得鄰國選舉的問題上是相當團結的。美國的選舉震驚了世界，投票公司有時會問其他國家的選民，如果他們可以的話，他們會把票投給誰。包括在2016年的總統(tǒng)大選中，加拿大人始終表明，他們對民主黨人的偏愛超過了共和黨人。因此，Retnakaran和Ye研究了在選舉前后安大略省出生的男孩和女孩的數(shù)量。

In BMJ Open, they report a sharp dip in the proportion of boys born in March 2017, which slowly returned to normal in the following months.

在BMJ公開賽上，他們報告說2017年3月出生的男孩比例急劇下降，在接下來的幾個月里慢慢恢復正常。

Effects usually show up 3-5 months after tragedies, but because there could have been many other explanations, the authors drilled down further into the data. Left-leaning parts of Ontario saw an even larger shift than the provincial average. More conservative areas had no change at all. Even many conservative Canadians preferred Hillary Clinton to Donald Trump, but it is to be expected they were less distressed by the result than their counterparts who support the (Canadian) Liberals, NDP, or Greens.

這些影響通常在悲劇發(fā)生3-5個月后才顯現(xiàn)出來，但因為可能有許多其他的解釋，作者進一步深入研究了數(shù)據(jù)。安大略左傾地區(qū)的變化甚至比該省的平均值還要大。較為保守的地區(qū)則完全沒有變化。甚至許多保守的加拿大人也更喜歡希拉里·克林頓，而不是唐納德·特朗普，但可以預見的是，與支持(加拿大)自由黨、新民主黨或綠黨的加拿大人相比，他們對選舉結果不那么沮喪。

Although the full reason bad news affects birth ratios remains debated, male fetuses are known to be more susceptible to maternal stress than female ones. Considerably more boys than girls are conceived, but a higher rate of miscarriages brings the ratio closer to balance at birth. Anything that causes a spike in pre-term deaths will therefore show up in the sex ratios, given a sufficiently large sample. The effect can even be seen in seasonal data, with hot summers or cold winters having a small but noticeable impact.

盡管壞消息影響出生率的完整原因仍有爭議，但眾所周知，男性胎兒比女性胎兒更容易受到母親壓力的影響。懷上的男孩比女孩多得多，但較高的流產率使這一比例在出生時更接近平衡。因此，只要有足夠大的樣本，任何導致早產死亡激增的因素都將出現(xiàn)在性別比例中。這種影響甚至可以在季節(jié)數(shù)據(jù)中看到，炎熱的夏季或寒冷的冬季產生的影響雖小，但很明顯。

The authors acknowledge that without knowing the politics of individual expectant mothers, they can't be certain the election, rather than some other event around the same time, caused the effect they measured, but the timing and distribution are striking.

作者承認，如果不了解準媽媽們各自的政治傾向，他們就無法確定是選舉，而不是與此同時發(fā)生的其他事件，導致了他們所測量的影響，但時間和分布是驚人的。