生育高峰与经济走强往往息息相关，为什么如今美国生育率却创造了历史新低？

美国去年诞生的婴儿数量是近三十年来最低，总共只有3,853,472人，同比下降2%。

这是美国连续第三年出生人数下滑，2017年每一千名15-44岁女性只诞生60.2人的生育率也创造了历史新低。生育率唯一增长的群体是那些40岁出头的妇女，而青壮年的生育率暴跌7%，这也意味着比起2007年，如今青壮年的生育率已经下滑了55%。

生育率整体下滑带来的明显问题就是美国人口的老龄化，更多的老龄人需要社会保障，而缴纳社保的年轻人则变得更少。

另一件有趣的事情是生育率下滑和经济的增长出现了不匹配的现象。原本，经济好转往往会与生育高峰挂钩。

根据美联社的报道，专家认为生育率下滑也许是因为千禧一代对母亲身份的看法出现了转变——本质上，他们更倾向于推迟生育，不养那么多小孩——以及长期避孕措施的使用增多所致。

针对30多岁的女性生育率出现轻微下滑的情况，宾夕法尼亚大学（University of Pennsylvania）的人口学家汉斯-彼得·科勒对美联社表示：“目前很难说这标志着根本性的变化还是仅仅一点波动。”这种下滑表明之前的趋势出现了扭转。

这些最新的临时数据来自美国疾病控制与防治中心（Centers for Disease Control and Prevention）的全国健康状况统计中心（National Center for Health Statistics）。

该中心的统计学家布雷迪·汉密尔顿对《华尔街日报》表示，他“对青少年生育率的持续下降非常震惊”。这种下滑至少有部分原因在于避孕措施的使用率在青少年中有所增加。（财富中文网）

译者：严匡正 

The U.S. last year saw its lowest number of births in three decades—a total of 3,853,472, which was down 2% from 2016.

This is the third annual decline in a row, and 2017 also saw a record low fertility rate of 60.2 births per 1,000 women aged 15-44. The only group to see birth rates rise was women in their early 40s—the birth rate for teenagers was down a whopping 7%, meaning the teen birthrate is now down 55% from 2007.

The obvious problem stemming from the overall decline is that America’s population is aging, which means more older people who may need a social safety net and fewer younger people to pay into the systems that provide it.

What’s also interesting is the mismatch between the declining birth rate and the economy, which is booming. Good economic times usually go hand-in-hand with baby booms.

According to an AP report, experts say the falling birth rate may be due to millennials’ changing attitudes about motherhood—essentially, they’re more inclined to put it off and have fewer kids—as well as increased use of long-term contraception techniques.

“It’s difficult to say yet whether it marks a fundamental change or it’s just a blip, University of Pennsylvania demographer Hans-Peter Kohler told the AP, in reference to the slight decline in birth rates for women in their 30s. That decline marked a reversal of the previous trend.

The new provisional figures come from the Centers for Disease Control and Prevention’s National Center for Health Statistics.

A statistician at the Center, Brady Hamilton, told The Wall Street Journal that he was “absolutely astounded at the continuing decline in teen birthrates.” That decline appears to be at least partly attributable to teens’ increased use of birth control.