If you’ve ever given birth vaginally — you know, in your spare time when you were bored and had nothing better to do — you’ll have no trouble believing that human childbirth is a hot traffic-jam of a mess compared to the slip-and-slide births of other primates. Chimp and gorilla mamas sneeze and bam! Cute primate baby. Meanwhile, we poor human mothers are mooing, clawing the sheets and praying our baby’s head won’t get stuck in the metaphorical elevator doors. What gives?
For some sadistic, unknown reason, a human infant’s head is designed to just barely squeak through its mother’s pelvis. Because of this, we poor human mothers are far more likely to be at risk for fetopelvic disproportion, a life-or-death condition in which either the baby’s head is too large or Mama’s hips are too narrow for safe vaginal delivery.
It’s no secret that C-sections have risen in popularity for decades. They now make up fully 30 percent or more of all deliveries in the U.S. Scientists are now paying close attention to this trend because it turns out all those C-sections may just be changing the way we humans evolve.
In layperson’s terms: Because Caesarean sections have reduced mortality rates in mothers, our trusty, if brutal, “survival of the fittest” gene selection has been watered down. Some scientists are now predicting that there will be an “evolutionary response” — or a likely rise in fetopelvic disproportion rates — because teeny mothers and big-headed babies are surviving births far more often.
Which, of course, is great for the teeny mothers and the big-headed babies of the world. Survival is good stuff. But some scientists believe that fetopelvic disproportion, now hovering at around 3 percent of all births, will be on the rise.
So far, of course, this is just theory. “To my knowledge, this has not been shown empirically yet,” fetopelvic disproportion researcher Philipp Mitteröcker, an evolutionary biologist at the University of Vienna, explained in an interview with Vox.
Still, you heard it here: All those large-noggined infants and their small-boned moms may be shaping the course of human evolution. In time, we humans may become a species heavily populated by brainiacs and the slim-hipped… who require C-sections even more often if we dare keep reproducing. And so on. And so on.
We smell a sci-fi movie in the making — get Jennifer Lawrence on the phone.