There’s a reason why so many babies are born in September. People’s interest in sex spikes during major religious holidays, and it’s not due to the eggnog. A study published in the journal Scientific Reports shows a correlation between holidays and an increase in online interest in sex as well as the birth of babies nine months later.
It’s long been theorized that increases in sexual desire corresponded with the changing of seasons. But researchers discovered that people’s interest in sex is driven by cultural events. And it happens regardless of where they live in the world.
Researchers examined the phenomenon as it pertains to Christian countries and following the Muslim festival Eid-Al-Fitr, which occurs after Ramadan and takes place at different times every year.
The scientists explained: “Here we show that interest in sex peaks sharply online during major cultural and religious celebrations, regardless of hemisphere location. This online interest, when shifted by nine months, corresponds to documented human births, even after adjusting for numerous factors such as language and amount of free time due to holidays.”
Co-author Luis Rocha, a professor at the Indiana University School of Informatics, Computing and Engineering, told the Independent: “We didn’t see a reversal in birth rate or online interest in sex trends between the Northern and Southern hemispheres. It didn’t seem to matter how far people lived from the equator. Rather, the study found culture – measured through online mood – to be the primary driver behind cyclic sexual and reproductive behaviour in human populations.”
The researchers also examined people’s tweets from Argentina, Australia, Brazil, Chile, Indonesia, Turkey and the United States. The report explains: “We further show that mood, measured independently on Twitter, contains distinct collective emotions associated with those cultural celebrations. Our results provide converging evidence that the cyclic sexual and reproductive behaviour of human populations is mostly driven by culture and that this interest in sex is associated with specific emotions, characteristic of major cultural and religious celebrations.”
The researchers developed a sentiment score, which they matched to sex-related searches on Google in the weeks leading up to, during, and following a major religious holiday. They found during religious holidays there was an increase in interest in sex and people were happier.
Holidays such as Easter and Thanksgiving didn’t show the same increase in sexual interest as Christmas and Eid.
The researchers concluded: “Our analyses provide strong converging evidence for the cultural hypothesis: human reproductive cycles are driven by culture rather than biological adaptation to seasonal cycles.
“Furthermore, the observed peaks of interest in sex occur around family-oriented religious holidays, across different hemispheres and cultures, and the measured collective mood on these holidays correlates with an interest in sex throughout the year, beyond these holidays.”