Why More Babies Are Conceived in the Cold Winter Months

September is most common month for birthdays, and if you count backwards from there, you may think, oh yeah, holiday celebrations and alcohol, long nights and cold weather, sure. That's the conventional wisdom, but September is not the most common birth month in all places. Scientists believe there are more natural reasons for peaks in human births that depend on climate and daylight more than cultural practices. In animals, evolutionary forces insure that births peak at the time of year that helps babies to survive, such as when resources are plentiful. The same forces may be at work in humans.       

There is a clear pattern of births across latitude. Here in the U.S., states in the North have a birth peak in early summer (June-July), while states in the South experience a birth peak a few months later (October-November).

Globally, popular birthdays follow a similar pattern with peaks occurring earlier in the year the further north you get from the equator – for instance, Finland’s is in late April, while Jamaica’s is in November. And in the U.S., states further south, like Texas and Florida, experience birth peaks that are not only later in the year, but also more pronounced than those seen in the North.

These peaks may have to do with temperatures conducive to newborn survival, or possibly the threat of disease- while diseases evolve even faster in order to take advantage of victims. Anyhow, the seasonal effect of birth rates is lessening due to birth control and a disconnect from our natural environment. Read more about seasonal birth rates and the possible reasons behind them at Smithsonian.

(Image credit: Arteida MjESHTRI)

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I've been around long enough to know that people will have sex, regularly if they can, no matter what the weather. The research on the seasonal births has to do with fertility, not behavior.
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Not only is that not true, nor funny, but it's a pretty bigoted description of life in Africa.

To start, in Tanzania with one of the highest rates of lion attacks, about 50 people die from lion attacks (I can't find solid numbers; https://en.wikipedia.org/wiki/Lion#Man-eating says about 37 per year in the 1990s), while 18K people die from traffic accidents.

The usual explanation is lack of education, especially for women, distrust of prophylactics, religious views (eg, the strong influence in Africa of the Catholic Church's fight against condom use), and the view that children will provide more help with the household chores. Yes, the Catholic Church is far more responsible than any fear of lions.
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I guess one could apply the same logic to hot regions too. Why do African peoples have so much children? Because amidst all the heat, malaria, lion attacks - having kids probably makes you feel better about your situation.
Pressure makes diamonds :)
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