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Are More C-Sections Actually Changing Human Evolution?

A new study looks at how the increase in C-sections may be creating changes to the human body as we know it.

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Remember studying Darwinism and natural selection back in school? Yeah, I've tried to block it out, too. But a new study out of Austria, published in the journal Proceedings of the National Academy of Sciences (PNAS), looks at how the increase in C-sections may actually be changing human evolution, and it's just too fascinating to not learn about.

The study, conducted by Philipp Mitteröcker, an evolutionary biologist from the University of Vienna, and his team, suggests that there may be an evolutionary reason why so many babies are being born via Cesarean section. (Consider that according to the CDC, C-sections now make up 30 percent of U.S. births.) So the theory is that due to the increase in this type of delivery, newborns' heads are able to grow too big for moms to birth them vaginally. And so the circle goes round and round. More C-sections equals babies' heads growing bigger, and thus, even more C-sections.

Think about it; before C-sections were an option, due to natural selection, babies with larger heads would not be able to pass through their mothers' narrow pelvises (a phenomenon researchers call fetopelvic disproportion), and sadly, many moms and babies would not survive childbirth. As The Huffington Post points out, their genes would not be passed down to the next generation.

But now, those babies and moms are surviving. Cue movie soundtrack music from when the main character has a major revelation. Because that's like, whoa, right?

Mitteröcker admits this is just a mathematical hypothesis for now. It's also a fact that a baby having a large head, and/or a mother having a narrow pelvis, are far from the only reason for C-section births. Consider too that many babies have large heads, and are still successfully birthed vaginally.

Still, that C-sections are on the rise is potentially problematic given the inherent health risks associated with these deliveries, including an increased risk of obesity and asthma for babies later in life.

In the end, this new study is undoubtedly making headlines because it may be true. But the bottom line is that each pregnancy is different; each delivery is different. And when it comes down to it, you have to do what's best for you and your baby, with the guidance and support of your doctor or midwife, be it a vaginal or Cesarean delivery, regardless of human evolutionary theory.

Melissa Willets is a writer/blogger and a mom. Find her on Facebook where she chronicles her life momming under the influence. Of coffee.