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"The New Puberty: How to Navigate Early Development in Today's Girls"
"The New Puberty: How to Navigate Early Development in Today's Girls"

Girls are hitting puberty at much earlier ages these days. In "The New Puberty," Dr. Louise Greenspan and Dr. Julianna Deardorff explain what's behind the phenomenon and what parents can do about it.

What happens when a girl has the body of a 13-year-old, but the brain of an 8-year-old? It sounds like a riddle, but it's actually a real life challenge facing lots of kids today.

Girls are hitting puberty at much earlier ages these days, and parents are struggling with how to respond. It's what led Dr. Louise Greenspan and Dr. Julianna Deardorff to write "The New Puberty: How to Navigate Early Development in Today's Girls."

They joined Take Two to explain why puberty is happening earlier for some girls, what can be done to prevent it, and how parents can help their daughters through the changes.


Is She Entering Puberty Early?

Isabel's transition into puberty was like that of millions of other girls, from a purely physical standpoint. After Isabel complained of discomfort in her left nipple, her mother noticed a bump under it that started to grow bigger. Within a few weeks, the same thing happened to her right nipple. The pediatrician noticed that Isabel's height had edged out of the average range since her last visit, and she was now taller than most of her peers. When the doctor examined Isabel's breasts, she confirmed that Isabel was developing breast tissue even though she had no pubic hair yet.

All of this would have reflected an ordinary start of puberty had it not been for one significant difference: Isabel wasn't a preteen with dreams of dancing with her current crush. She was just 7 1/2 years old. When the doctor ordered a bone age x-ray, which would reveal how "old" Isabel was from a physiological standpoint, the results indicated that Isabel's bones were as biologically mature as those of a 9-year-old. (An image of the wrist and hand can determine if there's been long-term estrogen exposure, which causes early maturation.) Further testing demonstrated that the hormones responsible for triggering her physical changes were coming from her pituitary gland, the initiator of puberty, which signals certain hormones to instigate the process. To rule out any rare anomalies like a brain tumor that could have sparked puberty, the doctor also ordered an MRI. Fortunately, it didn't reveal any abnormalities, so Isabel was deemed to be an otherwise healthy girl beginning puberty during the phase of her life when she was still playing house with her dolls.

Welcome to the new puberty.

Early puberty statistics

If you've found yourself in panicky discussions with other parents or been reading media coverage about girls developing faster these days and entering puberty at an earlier age than previous generations, the reports are true. Indeed, a growing number of young girls are being catapulted into early physical development long before they are socially and emotionally ready for the change. According to the National Institutes of Health, puberty typically happens between ages 8 and 13 for girls, ending with sexual maturity and the ability to reproduce. Just a generation ago, less than 5 percent of girls started puberty before the age of 8; today, that percentage has more than doubled. In fact, our longitudinal study as part of the Breast Cancer and the Environment Research Program (BCERP), which assessed the onset of puberty in more than 1,200 girls who have been tracked since 2005 across three cities and was published in the medical journal Pediatrics in 2010, found that by age 7, more than 10 percent of Caucasian girls in America had started growing breasts, along with almost 25 percent of African American girls and 15 percent of Hispanic girls. And by age 8, those percentages had spiked to 18, 43, and 31, respectively. This begs the question: What's going on?

What early puberty looks like 

We'll answer that important question in this book. What hasn't changed is that puberty typically starts with breast development, then armpit and pubic hair, acne, a growth spurt, and, finally, menstruation. While it's easy to start wondering how environmental chemicals or dietary choices may be affecting our children's development, the new puberty reflects a much more complex set of circumstances than most people think. And it's often not nearly as dramatic as some feature stories would have you believe. Although many journalists have portrayed extremes, profiling 5-year-olds with the body odor of a teenager and shopping for bras with their mothers before heading to kindergarten, such examples are truly exceptional. The facts of early puberty for most girls are much less intimidating. In fact, even the words "puberty" and "normal" are grossly misunderstood by many people because popular perceptions of what is meant by these terms don't reflect the scientific literature. The good news is that despite the media's somewhat sensationalistic slant on this rapid turn of events for modern girls coming of age, this book aims to quell fears that going through puberty early is necessarily "bad" (or that there's something "wrong").

Dealing with early puberty

That said, traditional wisdom about how to help a child through puberty falls short when it comes to caring for a girl facing this transition early in her life. Parents, teachers, and professionals who work with children need much more than advice on how to talk about physical changes and sex; they require a host of skills that will help them teach girls how to appreciate and love their changing bodies and nurture their evolving identities, and also to help girls manage the eventual health risks their early puberty might carry. (Often these conversations don't even mention the birds and the bees.)

Types of early puberty

Girls who enter puberty early fall into two categories: There are the rare girls with known disorders like Central Precocious Puberty, wherein a girl's pubertal process starts abnormally early for unknown reasons or due to a defect in the nervous system, and then there are the bulk of the girls, who simply develop on the early side of the normal curve. But defining this "normal curve" has been a moving target for us in the medical community. Continual shifts in our scientific thinking about what characterizes a healthy normal-but-early puberty have not only provoked some debate among the experts who study it, but also led to much confusion and misinformation among the public. Throughout this book, we will dispel myths that have unfortunately begun to circulate over the last decade, since "early puberty" became a popular topic for discussion.

Common concerns with early puberty

Take a moment to consider some of the questions that are probably on your mind as you begin this book. Is soy really an estrogenic time bomb? Do hormones in meat and dairy hurt a girl's reproductive health? Can early puberty be stopped or reversed? Should it be? What's causing girls to start their pubertal process at younger ages today? How could things have changed so much in just one generation? These are questions we field routinely--from parents, teachers, school administrators, doctors, and health professionals--and we trust you'll be as surprised and reassured as they have been by our answers. For those who are seeking immediate solutions for guiding and nurturing rapidly developing girls, either because you work in some capacity with such girls or because you have a daughter of your own, we will provide highly practical strategies (e.g., lists of things to do or avoid and scripts for talking to girls) for supporting children going through this experience. Whether you care for a girl who is years away from puberty or one who is already in the throes of this important transition, this book will help you prepare for whatever lies ahead. We understand the unique set of challenges that arise when puberty begins for a girl who hasn't even begun to fathom what that means or what's ahead of her.

About the researchers

Before we present an overview of the upcoming chapters, let us tell you a little about ourselves. We've been working in the trenches of child and adolescent health in both clinical and research settings for years, nearly our entire professional lives, and between us, we have covered every angle of the early puberty phenomenon. In 2005, we--Louise Greenspan, a pediatric endocrinologist, and Julie Deardorff, a clinical psychologist--teamed up to study the complex nuances inherent in the new puberty, which eventually inspired us to write this manual for managing its potential effects, from blessings in disguise to serious hazards. People affected by early puberty, from panicked parents to educators and leaders in health care, have long urged us to combine our wisdom to create a scientifically grounded and practical book that addresses their concerns. And this is just what we've done. Even though we're still in the midst of our research and unveiling new insights every day, we've accumulated plenty of knowledge over the past decade to create an essential guide that can equip you with the information you need to traverse this terrain. Some of our most helpful information stems from the encounters we have had with individuals and families who live and breathe this new reality daily.

We should also add that aside from our professional jobs as doctors and scientists, we are mothers of girls, too. We go home every day to young daughters who are entering puberty themselves. We compare our notes and observations all the time from a deeply personal perspective, for we've pondered all of these emotional and sometimes thorny issues as parents as well as providers. And we practice the rules we preach in this book in the hope that our own loved ones will enjoy a most fulfilling, good long life.

Reprinted from The New Puberty by Louise Greenspan, MD, and Julianna Deardorff, PhD. © 2014 by Louise Greenspan MD, and Julianna Deardorff, PhD. By permission of Rodale Books. Available wherever books are sold.

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