據預測，在氣候變化的極端高溫下，嬰兒會出生得更早
據預測，在氣候變化的極端高溫下，嬰兒會出生得更早
When it comes to pregnancy and babies, the closer to full-term the better. Compared to full-term pregnancies, we know that near-term babies have a higher risk of medical problems soon after birth, and lower cognitive outcomes later in childhood.
說到懷孕和嬰兒，越接近足月越好。與足月妊娠相比，我們知道，早產嬰兒在出生后很快就有更高的發(fā)生醫(yī)學問題的風險，而在兒童后期的認知結果則更低。
So, with that in mind, we have some bad news. Researchers have found that extreme heat makes babies rush to the exit sooner, leading to an average of 25,000 US infants a year born a little early due to hot weather.
所以，考慮到這一點，我們有一些壞消息。研究人員發(fā)現(xiàn)，極端高溫會使嬰兒更快地離開媽媽，導致每年平均有25000名嬰兒因天氣炎熱而提早出生。
And like nearly everything else in this world, it's only going to get worse with climate change.
就像這個世界上幾乎所有的事情一樣，氣候變化只會使情況變得更糟。
"Given recent increases in the frequency of extremely hot weather, there is a clear need to better forecast the potential magnitude of climate change's impact on infant health at the national level," the team explains in their paper.
研究小組在論文中解釋說：“鑒于最近極端高溫天氣的頻率增加，顯然需要更好地預測氣候變化對國家一級嬰兒健康的潛在影響程度。”。
"We find that extreme heat causes an increase in deliveries on the day of exposure and on the following day and show that the additional births were accelerated by up to two weeks."
“我們發(fā)現(xiàn)，極端高溫會導致暴露當天和第二天分娩量增加，并顯示額外分娩的速度加快了兩周。”
The two researchers - economists Alan Barreca from the University of California, Los Angeles and Jessamyn Schaller from Cambridge - used US birth rates and temperature data between 1969 and 1988 to get a handle on just how many extra babies were being born on hot days.
這兩位研究人員——加州大學洛杉磯分校的經濟學家艾倫·巴雷卡和劍橋大學的杰西曼·夏勒——利用美國1969年至1988年間的出生率和氣溫數據，來了解在炎熱的天氣里多生了多少嬰兒。
Although past studies have looked at this from the view of gestational length, the researchers explain this can be affected by misreporting and can lead to less accurate results.
盡管過去的研究都是從孕長的角度來看待這一點，但研究人員解釋說，這可能會受到誤報的影響，并可能導致不太準確的結果。
Instead, the team looked at daily birth rates across the whole of the US, including a whopping 56 million births in their data.
相反，該研究小組研究了美國全境的每日出生率，數據中包括高達5600萬的出生率。
"We advance the methodology of temperature–gestation studies by using data on daily birth rates, as opposed to recorded gestational lengths," the team explain.
研究小組解釋說：“我們通過使用每日出生率的數據，而不是記錄的妊娠期長度，來推進溫度-妊娠研究的方法。”。
This works by analysing the data for a spike in births on hot days, and then checking if there is a subsequent decrease afterwards.
這項工作的原理是，分析高溫天出生高峰的數據，然后檢查隨后是否有下降。
"For example, in a given county of the United States, an increase in birth rates on the day of hot weather followed by a decrease two days later suggests temperature reduced gestational lengths by two days."
例如，在美國的一個縣，天氣炎熱時出生率上升，兩天后出生率下降，說明溫度使妊娠期縮短了兩天。
They estimate that in the US, this led to 25,000 babies a year that were born a little earlier than scheduled due to heat exposure, creating a total loss of over 150,000 gestational days annually.
他們估計，在美國，這導致每年有25000名嬰兒因熱暴露而比預定時間稍早出生，每年造成超過150000個妊娠日的總損失。
Although a couple of days less gestation time isn't an issue for every baby, shorter gestation times have been linked to lower health and cognitive outcomes, and giving babies the best start in life means we should probably be trying to keep them a little cooler.
雖然對每個嬰兒來說，縮短幾天的懷孕時間并不是一個問題，但縮短懷孕時間與降低健康和認知能力有關，給嬰兒最好的人生開端意味著我們應該盡量讓他們保持涼爽。
We know that our climate is heating up, and without serious action, it's going to get worse. This means more hurricanes, wildfires, and heatwaves.
我們知道我們的氣候正在變暖，如果不采取認真的行動，情況會變得更糟。這意味著更多的颶風、野火和熱浪。
What this study shows is that it's not just the humans who have already been born that will be feeling the negative effects of the mercury rising.
這項研究表明，不僅僅是已經出生的人類會感受到水銀上升的負面影響。
"At the end of the century (2080–2099), we estimate that there will be approximately 253,000 additional lost days of gestation per year on average in the United States, affecting nearly 42,000 additional births," the team write.
“在本世紀末(2080—2099)，我們估計在美國平均每年會有大約253000天的妊娠損失，影響近42000的額外分娩。”研究小組寫道。
The paper has been published in Nature Climate Change.
這篇論文發(fā)表在《自然氣候變化》雜志上。
