And a new study shows that genetics may be a factor: inherited traits, such as impulsivity, can make a person more or less willing to have sex at an earlier age.

• 另外最近的研究表明基因也许是一个决定“破处”早晚的因素：在遗传性状中，如是否易冲动，会影响到一个人是否会在较小的年龄时就发生性行为。