by Maggie Downs posted in Life

There was really only one thing that came naturally to me after I gave birth to my son, and that was holding him on my left side. I snuggled him in the crook of my left arm, I rocked him with my left arm. And as he grew a little older, I slung him on my left hip and carried him around.
I hauled him around on my left side, even when that side of my lower back began to ache, even when it felt like I was squeezing part of my spine like an accordion.

 
Even my husband did it.

 
It's not just us.
It turns out 70 to 80 percent of women carry their babies on their left side, according to this study.

Remarkably, this is something that begins long before women ever give birth: "The bias appears prior to maternity and is demonstrated early in ontogeny; even preschool-age girls show a clear left preference when holding a doll the size and weight of a newborn baby," the study says. But why"
A study published earlier this month could hold the key. The Biology Letters journal says Pacific walruses and Indian flying foxes also show a significant bias toward the left side for mothers and their babies. The researchers studied those animals specifically because the mothers and babies in those two species are known to hang out both side-by-side as well as face-to-face.
The researchers hypothesize that mothers keep babies toward the left to aid in communications, since information from the left visual field is processed by t...