The rock band Dr Hook once lamented¹ that "when you’re in love with a beautiful women, it’s hard".

摇滚乐队Dr Hook曾经在歌曲中哀叹道：“当你爱上一个美丽的女人，（想守住她）太难了。”

But a new study suggests it is the less attractive ladies who are responsible for the greatest heartache.

但一项新研究指出，最难守住的其实是不漂亮的女人。

When US researchers followed more than 200 married couples for three-and-a-half years, they discovered that women who considered themselves attractive were far more likely to be faithful.

美国研究人员在三年半的时间里跟踪调查了200多对已婚夫妇，他们发现，认为自己有魅力的女人保持忠贞的可能性要大得多。

They also found that women who had been more promiscuous² in the years before their marriage were less likely to cheat.

他们还发现，结婚前比较放荡的女性在婚后出轨的可能性较小。

In contrast, less-attractive females who had limited sexual experience were more likely to engage in extra-marital³ entanglements⁴.

相比之下，婚前没什么性经历又不太有姿色的女性在婚后更容易卷入婚外情。

The researchers from Florida State University followed 233 newly married couples documented intimate details about their relationships, including marital satisfaction, long-term commitment, whether they had engaged in infidelity and if they were still together.

来自佛罗里达州立大学的研究人员跟踪调查了233对新婚夫妇，记录了他们婚姻感情的私密细节，包括婚姻满意度，长期承诺，是否有过不忠行为，以及是否仍然在一起。

Writing in the Journal of Personality and Social Psychology⁵ lead author Jim McNulty said: "Specifically, own attractiveness was negatively associated with infidelity among women, but not men, suggesting that less attractive women were more likely to engage in infidelity.

该研究的首席作者吉姆·麦克纳尔提在《人格与社会心理学杂志》上写道：“具体而言，女性自身的魅力值和不忠倾向呈负相关，但是男性则没有这种情况。这意味着不漂亮的女性更可能不忠。”

"Men were more likely to engage in an infidelity when their partners were less attractive. This latter sex difference is consistent with evidence that partner attractiveness is more important to men than it is to women."

“当男性的伴侣缺少魅力时，男性更可能出轨。有证据显示，伴侣的魅力值对于男性比对女性更重要，这和刚才提到的性别差异是一致的。”

Surprisingly, the researchers found people satisfied with sex in their relationship were more likely to cheat, perhaps suggesting they felt more positive about sex in general and would seek it out regardless of how they felt about their main relationship.

出人意料的是，研究人员发现，对性生活满意的人更可能出轨，也许是他们对性的心态更积极，所以无论婚后感情好不好，他们都想要。

The study also found that people who are less likely to stray are far better at removing their attention quickly from an attractive stranger.

研究还发现，较不可能出轨的人能很容易地将注意力从一个有魅力的陌生人身上快速移开。

Individuals who looked away from pictures of highly attractive people a few hundred milliseconds faster than average were nearly 50 percent less likely to have sex outside marriage.

在看到颜值高的照片时，移开视线的速度比平均水平快几百毫秒的人发生婚外情的概率会降低50%。

"With the advent⁶ of social media, and thus the increased availability of and access to alternative partners, understanding how people avoid the temptation posed by alternative partners may be more relevant than ever to understanding relationships," added Dr McNulty.

麦克纳尔提博士补充道：“随着社交媒体的出现，和可选择伴侣的接触机会增多了，理解人们如何抵御这些可选择伴侣构成的诱惑，也许对于理解感情关系比以往都更有意义。”