Not that you want to do this but there is an easy way to speed up a woman's reproductive timing - just get a clock.

Not one of those modern digital things, an actual ticking clock will literally do it, says a paper upcoming in Human Nature.

It turns out that the tick-tock of the metaphor has some basis in reality. Or not. The authors also claim that poor women are more likely to be affected by this ticking sound. And the authors are psychologists so beware of mainstream media making grand biological claims based on this.

Psychology graduate student Justin Moss and Professor Jon Maner of Florida State University conducted two experiments, priming the idea of the passage of time through the sound of a ticking clock. In the first, 59 men and women were asked questions about the age at which they'd like to marry and start a family. The goal was to assess how socio-economic background might influence some people to delay their desire to have a family, or begin to act on it. In the second experiment, the researchers examined to what extent 74 participants would alter the characteristics they normally sought in potential mates to possibly settle for less just in order to have children sooner. 

They found that women from poor backgrounds were more likely to want to get married sooner, those with wealthier backgrounds wanted to start families later. 

They conclude that men easily father children in old age and women don't and so a ticking clock can be a literal biological impetus.

"The findings suggest that a woman's childhood years can interact with subtle environmental stimuli to affect her reproductive timing during adulthood," adds Maner.

Is that a biological clock? No, but it is a cultural one that impacts the biological world. You win this one, mothers of the 1950s.

Citation: Moss, J.H.,  Maner, J.K. (2014). The Clock Is Ticking: The Sound of a Ticking Clock Speeds Up Women's Attitudes on Reproductive Timing. Human Nature. DOI 10.1007/s12110-014-9210-7