We all know the wink-wink-nudge-nudge anecdotes our friends share about how they were conceived: “I’m born in September. Guess my parents had fun on New Year’s Eve!” Turns out these tales of wintery fertility and summer romance have grounds in scientific fact. A number of studies have demonstrated the effects seasonal changes have on our sexuality. As we approach midwinter in the Southern Hemisphere, here are five of those changes to look out for.
Human sexuality likes extremes…
Multiple studies seem to suggest that there are two peaks in human sexual activity and libido: summer and winter. One Google keyword search analysis showed an uptick of sex-related search terms such as pornography and dating sites during summer and winter. This is consistent with birth trends in northern climates peaking in early spring and autumn, corresponding with conceptions in the summer and early winter.
…But men and women’s sexuality is affected differently
Though these bimodal peaks exist, they appear to apply to men and women differently. Women were reported to have a greater libido in the spring, while a study of 114 heterosexual men revealed that they found the female body more attractive during the winter months. Researchers theorised that this might be due to a decreased exposure to the female body during winter, or heightened testosterone levels. Women’s hormones, on the other hand, are more sensitive to their surroundings; thus their sexual interest increases with an increase in daylight.
Men are at their spermiest in the winter.
While men’s sexuality is assumed to be the most stable throughout the year, the same can’t be said of their fertility. Researchers in a 1991 study found that during the summer – particularly in countries with hot summers – men’s semen quality deteriorates with the heat. Specifically, the quantity and concentration of sperm per ejaculation is far lower during the hotter months. The study also showed a run-on effect into early autumn. So give a thought to your little fellas while you smash through tinnies and stoke the barbie next summer. STRAYA!
Women’s fertility is similarly affected.
Studies have also found that a correlation between seasons and physiological changes in a woman’s body. A 2005 study found that women born in spring experience an earlier onset of menopause. This may be because babies born in spring tend to born with a smaller number of eggs in their ovaries (yes, babies are born with a lifetime supply of eggs already in their ovaries) and run out quicker. Studies have seen a similar trend in menarche (a woman’s first period): the start of menstruation peaks during summer and winter.
Winter will have you watching rom-coms
If summer is often thought of as fling season, winter is its cosy romantic counterpart. Science seems to back up the latter assumption. In a 2012 study, researchers found a correlation between winter and willingness to watch romantic movies – even in males, often thought to dislike the genre. The inference drawn was that physical coldness activates a need for psychological warmth – which manifests as things such as a hot beverages, physical closeness and – yep – romance movies. Something to keep in mind when you convince yourself you’re only “hate-watching” that Ashton Kutcher rom-com.