Motherhood certainly makes us tired, but can others see that just by looking at our faces?
Motherhood certainly makes us tired, but can others see that just by looking at our faces? A new study says yes!

It's an age-old debate: Does having children age you or keep you young? A new study published in the American Journal of Anthropology claims that there are costs to reproduction for a woman. Specifically, the study concluded that the more children that a woman had, the less attractive others found her to be.

Polish researchers gathered images of post-menopausal women and categorized them according to the number of children that each woman had birthed. To eliminate any possible bias, the researchers utilized computer software to create "average facial images." The researchers then asked 571 male and female study participants to rate the faces' in terms of their youthfulness, attractiveness, and how healthy the faces appeared.

Despite being of similar age, the study found that those women who had given birth to fewer children were judged as younger, more attractive, and healthier than those who had more children. Further, the women who had the most children were consistently rated as older and less appealing.

Related Study: Some Advantages to Becoming a Mom Later in Life

The study authors confirm that while the association between having more children and aging is not apparent, one possible hypothesis is related to the higher levels of oxidative stress that occur during pregnancy.

Pregnancy, followed by lactation and childcare, require an increase in energy metabolism. Because the placenta is rich in mitochondria, pregnancy favors oxidative stress. Oxidative stress is an imbalance between free radical production and a body's ability to counteract their dangerous effects.

Dr. Huber Warner, a lead expert on aging and founder of the National Institute on Aging's Intervention Testing Program, said, "There's a hell of a cost for a woman to conceive and have a child in terms of just biological wear and tear. Let's just assume that in life you have a certain amount of energy to burn. If you burn it up having children there's less left to maintain the homeostasis [stable equilibrium] of the individual."

Related: In Defense of the Bigger Family

The study echoes a 2016 Yale University study which measured the number of biomarkers in a women's urine associated with oxidative stress. The study found that those women who experienced at least four pregnancies had 20 percent higher levels of the molecules that show oxidative damage to DNA.

While decisions on family size should not be made based solely on how you might look down the road, it's certainly food for thought!