Is "8" The New Teenager?

At our annual wellness exam, the pediatrician asked if I had noticed any signs of puberty. At age eight. I laughed, thinking this was a joke and then realized it was not. “No, should I? Doesn’t that start later?” Nope, I was told, puberty onset often starts at age eight. When I told my husband later, he literally cut me off with an incredulous “NO!” I had to explain this came from the pediatrician, not my own random thoughts.


Just a reminder that I have a pretty strong professional background in child development and have worked for over a decade in medical environments, understanding the important role of physiology and hormones in child development. And I still felt completely blindsided by this possibility in my oldest child.

Several days later, my daughter and I had an interaction that felt like a time machine transporting us instantaneously into adolescence. She reacted to something minor with a sudden and intense outburst of sobs and accusations. Hmmmm . . . is that part of puberty? Because it sure felt like I was in the room with a 13-year-old.

I asked around. One friend of a 7-year-old gasped in disbelief that puberty could be around the corner. Later, she told me she asked her husband (a physician for kids, incidentally) and he agreed that this was common knowledge. Another friend of two girls, ages 9 and 7, nodded with a knowing smile, and just said, “yep.” I also checked with a close friend whose son is several months older than my daughter, and she shared her story of rushing him to the pediatrician when she saw a tiny physical sign, convinced something was terribly wrong. It wasn’t.

I had sort of heard that puberty starts earlier these days, but I realized I did not have a full grasp of what that meant. Earlier than when -- when I was a kid? How early is normal? When do we know It has started (i.e. – sudden emotional outbursts)?

So I used our old friend, Dr. Internet, to see what is out there for the regular parent whose concern dawns in a moment that is not conveniently during a conversation with the pediatrician.

Some interesting highlights from a review, distilled to bullet points for easy reading of what is a pretty tedious topic reminiscent of high school biology:

  • 100 years ago, the average age a white girl (that’s who was studied) got her period was 17; now it is 12.6; this has changed only by a few months compared to 50 years ago
  • There are racial and ethnic differences: average age for starting a period in Mexican American girls = 12.2; average age for black girls in the U.S. = 12.1
  • “Normal” age for puberty onset is 8-13, and can take an average of 1.5 to 6 years (!)
  • The decline in average age for starting a period has plateaued BUT girls now develop breasts one to two years earlier than they did 40 years ago
  • The WHY for these changes is less fully understood, but there are some good reasons (eg, lower disease rates and better nutrition likely explain the lower age compared to 100 years ago) and some concerning reasons (eg, more exposure to “endocrine disruptors” from the environment and diet over the last few decades)

For all you parents of sons, it may or may not surprise you that a majority of the academic and media coverage of puberty centers on girls. There is a solid body of research showing that earlier puberty for girls can have many negative psychological and social effects, while the opposite is true for boys. Of course, this leads to a bigger discussion of why this would be true, and the differences in our society and culture of what it means to be a woman versus being a man. This is not the place for that discussion, but I think it’s important to tuck it away as possibly a part of understanding our reaction to the notion of our child starting puberty before WE are ready.

A New York Times article traced the history of medical research and recommendations. Based on 1960s studies of children in Britain, the average age of puberty was 11 for girls; an American Academy of Pediatrics study published findings in 1997 that the average age for breast budding was 9.96 for white girls and 8.87 for black girls. Another study published in Pediatrics in 2010 found that by age 7, breast development had started at different rates across racial and ethnic groups (10% of white girls, 23% of black girls, 15% of Hispanic girls, and 2% of Asian girls).

So, “normal” seems to have shifted over the last few decades, but what is abnormal and how do we know? Unfortunately, a routine pediatrician visit may not yield the definitive answer a worried parent seeks. This distinction between “normal” and “abnormal” onset of puberty has become blurred as the earliest age of onset has shifted. If you and a pediatrician are concerned, they could refer you to an endocrinologist who may recommend a bone age X-ray (a medical test that shows how well-matched one’s bone age is with chronological age). A mismatch between bone age and chronological age may indicate abnormally early or late puberty, an important marker for possible hormonal problems that could require medical intervention.

I haven’t yet answered my own question, though – could her outburst signal hormonal changes as part of puberty? In what I could find from the most straightforward sources, probably not (I did not dig into neuroscience, so it is possible the run-of-the-mill Google search of academic and media articles missed this). What I could find is what I already knew: first comes physical changes, kickstarted by a release of a hormone (GnRH). The emotional changes are simultaneous with this new hormone, and also happen simply because the experience of these changes can be upsetting and disconcerting. 

So, my daughter’s wellness visit and emotional outburst led me down quite the rabbit hole to either reassure or scare myself. I learned that yes, she is technically old enough to start puberty. And that may happen any day, and I personally need some time to psychologically prepare. However, changes in mood because of puberty hormones happen DURING and subsequent to puberty’s physical changes. I think my paranoia primed me for over-interpreting my child’s mood swing, a mood swing that probably happened because of that regular old brain and emotional development that seems to make every day of childhood a moving target.

But hey – I gave myself a warm-up lap before the actual race. And I am going to focus some gratitude on every childlike moment of innocence that all my pre-pubertal children give me.