Many people claim that there are more birthday gifts to buy and more birthday parties to attend in September than in any other month. Why is that so? Are more people born in September than in the other months? And if so, why?

An article published in the Business Insider quotes a study in the journal Obstetrics and Gynecology which claims that couples have a better chance to conceive in the winter months. This is apparently because men produce higher quality sperm during the winter months and the changes in daylight length make the woman’s ovum a better environment for the egg, the Business Insider reports. 

The study also notes that the celebratory nature of December (Christmas and the like) make it easier for couples to ‘hook-up’ and this is a possible behavioural explanation as to why so many people choose to conceive in December.

As far as India is concerned, the winter months are considered the ‘wedding season’ and due to the pressure many couples face (women far more than men) to produce a child for the marriage to be considered a success, this could perhaps explain the large number of babies born in the month of September.

According to a paper from the National Bureau of Economic Research, babies born during this month are also supposedly smarter. Why? In the United States, at least, September children are usually the oldest ones in their particular grade which can prove to be advantageous.

“Being an older age at school entry increases children’s college attainment and reduces the likelihood of being incarcerated for juvenile crime,” the research states.