Come winter time and early summer, we're on the internet looking for love, a new study has found.

By analysing Google keyword searches between January 2006 and March 2011 in the USA, scientists were able to identify a spike in love and lust-related searchers including for porn, dating and even prostitution.   

The fact that interest in sex peaked around Christmas time (which falls over winter in the USA) and early summer (just when the long summer vacation begins for schools), suggests that American citizens might just be affected by the holiday season.

The holiday effect has been documented before, mostly due to studying the consequences of sex - such as pregnancy and sexually transmitted disease (STD) which happen many months after the deed is done.

Detecting and anticipating this increase in sexual activity faster could help prevent unwanted pregnancy and the spread of STD through well-timed safe sex campaigns, which is why Patrick and Charlotte Markey at Villanova University in Pennsylvania and Rutgers University in New Jersey respectively, chose to analyse Google keywords.

By analysing the search trends such as "xxx", "boobs", "call girl" and "Match.com", and comparing these racier keywords with neutral ones such as "cat", "dog" and "restaurant", the two psychologists were soon able to identify the pattern. Along with these racy keywords, they found that porn keyword also saw a bi-annual spike in activity.

While the scientists rack their brains to discover concrete reasons for this twice-a-year peak in sexual activity, they speculate that it may have something to do with our primitive biological cycle.