The world’s least surprising study says that motherhood ages us about 11 years

On the hunt for a concealer that can hide the fact that you haven't had a proper night's sleep since giving birth?

You are not alone. It seems we are all in the same, sleep-deprived, knackered-looking boat. According to a study out of George Mason University, it seems becoming a mum not only plays havoc with our shut-eye and looks, it actually also ages us on a biological level. Yup – that's right, mums – you are now older than you years – says science. According to the research, women who had given birth showed signs of faster biological aging than women who hadn't—and the difference amounted to roughly 11 years.

To reach this conclusion, epidemiologist Anna Pollack and her team of researchers analyzed the DNA collected from roughly 2000 reproductive-age women in the U.S. in the National Health and Nutrition Examination Survey. They looked specifically at the length of the telomeres, which are chunks of DNA that cap the end of chromosomes to keep them from deteriorating. Stress, lack of sleep, poor diet, and aging all shorten telomeres, making you susceptible to degenerative diseases such as cancer, diabetes, heart disease, and premature mortality, while longer telomeres prevent disease.

After adjusting for age, ethnicity, education, and lifestyle habits such as smoking, the women who had given birth to at least one child had telomeres that were 4.2% shorter on average than those who hadn't.

And according to the experts, this percentage is equivalent to roughly 11 years of accelerated cellular aging. "We were surprised to find such a striking result," admitted Pollack, who adds that past studies equated childbirth to just four and a half years of accelerated cellular aging. "We found that women who had five or more children had even shorter telomeres compared to those who had none, and relatively shorter relative to those who had one, two, three, or four, even."

Well, that's great news. Oh, and get this: the researchers were keen to stress that it wasn't the actual giving birth bit that ages us so much, more the stress of looking after the child once it has arrived – as if this was news to you and me, mama. Now – what we'd now like to know is this: Is this the same for dads? Just because they haven't given birth, they are (or should be, at least) as involved in the stresses of bringing up baby, so could we expect to see them same results there?