Co-Sleeping Dads Have Lower Levels of Testosterone

Dads who sleep with babies, dream with less violence in their hearts. Well, not quite, but sort of…

An interesting study looking at family sleep habits in the Philippines and in America, revealed that co-sleeping dads had lower levels of testosterone than dads sleeping separately from their babies. Previous research suggests that the more time dad spends with his baby, the lower his testosterone and the higher his levels of oxytocin– the bonding or “cuddle” hormone.

It would make sense that co-sleeping would produce a similar effect.

Here’s what the lead researcher, Lee Gettler, an anthropologist at the University of Notre Dame, told the website LiveScience: “This suggests to us that active fatherhood has a deep history in the human species and our ancestors. For some people, the social idea that taking care of your kids is a key component of masculinity and manliness may not be new, but we see increasing biological evidence suggesting that males have long embraced this role.”

Here’s how the study was done: Researchers looked at bedtime and early morning testosterone levels and sleeping habits of 362 dads in the Philippines. The co-sleeping dads had lower testosterone at bedtime than the non-co-sleeping dads, but in the morning their levels were about the same.

Study authors note that the parenting culture is quite different in the Philippines compared to the US– most dads sleep with their babies, if not in the same bed very close by. They sleep on mats or mattresses on the floor. “The typical Cebuano sleep environment is much different than the U.S., generally lacking things like plush mattresses, box-springs, heavy duvets, etc.,” Gettler told Live Science. (These things make co-sleeping a safe option.)

Gettler seems less interested in co-sleeping, per se, and more in the way we think of masculinity and fathering: “If many human/hominin fathers have been actively taking care of their offspring for hundreds of thousands or millions of years, doesn’t that suggest that such behaviors should be considered a part of ‘what it means to be a man’ or manliness or masculinity?”

I’ve always been interested in how early parenthood affects our brain chemistry. It’s useful to have lower levels of testosterone and higher levels of oxytocin when you’re around a newborn. Taking care of a baby is really hard, the cuddle chemical is like a support system to help you through it. It’s also worth noting that in other research we see that dad’s testosterone levels may go down in the months after a baby is born, but the dip isn’t permanent. It’s a transitional state. Cool that dads go through these changes, too!



Ceridwen Morris (CCE) is a childbirth educator and the co-author of the pregnancy and birth guide From The Hips. Follow her blogging on Facebook.

Photo: Eric Wallace/Flickr

Article Posted 3 years Ago
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