Understanding and Preventing Early Puberty in Our Daughters

(Originally written October 2012; Updated April 2023)

When I was in sixth grade, at twelve years old, my breasts were more developed than many of the girls in my grade, leading to an enormous amount of unwanted ‘popularity' amongst the boys – ‘tittie poking' as they called it – and from men, too, in the form of glances, or the infamous NYC ‘cat calls” I frequently received and found terribly intimidating and even threatening. I wore oversized shirts, crossed the street or walked as quickly as possible past construction sites and groups of men, and  I tried to be less visible, because I often felt exposed, embarrassed, and even vulnerable. Perhaps you, too, have experienced something like this. 

Now imagine that, instead of 12, 14, or 16 when you did, you'd have been 8, 9, or 10 years old.

When I originally wrote this article in 2012, I described the growing trend toward earlier puberty as a pandemic-level crisis for our daughters. Now, after the COVID-19 pandemic, when I say pandemic, it may seem hyperbolic. And while nothing compares to the COVID crisis we’ve weathered, I would argue that early puberty is also an urgent crisis, one that also has ‘long' consequences, but that has been and remains largely overlooked and ignored by individual physicians, and has been ‘normalized' by healthcare agencies.. 

Speaking of pandemics: While this trend started toward earlier puberty began decades ago, we saw a significant international surge in earlier puberty onset during the COVID pandemic. Various studies have shown there's been roughly a doubling of rates of what is formally called “precocious puberty,” compared to the years prior to the pandemic, in countries as far ranging as Turkey, Germany, Italy, and South Korea.

As a mom of 3 daughters, a grandmother, and a women's and children's physician, I'm concerned about our girls’ reproductive health, and I’d like to share why that is. I’ll explore the causes behind the early puberty trend, and look at why we need physicians and policy makers to start advocating for our daughters so that they are not forced to experience biological entry into womanhood years before their minds and emotions are ready to bear the social consequences. I’ll also discuss what you can do to protect your daughters from the factors contributing to early puberty and how to support them through this life stage no matter what age they experience it.

The Falling Age of Puberty

In 1978, when  I was 12 years old and started to menstruate, I was exactly on the expected curve – most girls didn't experience menarche, the technical name for our first period, until about 13 years old. Breast development, or thelarche, typically begins a couple of years prior to menstruation – and is usually considered the official start of puberty. 

I was exactly in the norm amongst my girlfriends; the only girl I knew who'd begun menstruation much earlier was one of my best friends who had a diagnosed metabolic problem causing her to be medically obese, a factor which can lead to much higher estrogen levels – and thus puberty  at an earlier age. She got her first period, in my apartment, actually, on a school holiday, when she was nine years old. We figured out how to use one of my mom's menstrual pads by reading the box. It was  extremely rare at that time for a girl to begin menstruating this early, or even younger than my friend did, for example, by age 8.

For years scientists have disagreed whether early puberty was really an emerging phenomenon. Now there’s no doubt. In 1997, a landmark study found that at age 8, 48.3% of Black girls and 14.7% of white girls had breast development, warning that girls seemed to be entering puberty at younger ages than previously thought. According to a 2010 study, by the early 2000s, even more girls were entering puberty at younger ages: by age 7, 10.4% of white girls, 23.4% of Black girls and 14.9% of Hispanic girls had entered thelarche. At age 8, 18.3%, 42.9%, and 30.9%, had, respectively. This proportion was greater, particularly among the white girls, than that reported from studies of girls who were born 10 to 30 years earlier. According to a 2020 meta-analysis of global data, the average age of puberty’s onset dropped by about three months every decade from 1977 to 2013.

Enter Kotex, which spent over $23 million in research and development to target their new young consumer group, Kotex U, in 2011, aimed at girls 8 to 12. “Some girls get their period as young as 8,” begins a section for mothers on the Kotex U Brand website, with period products emblazoned with hearts and stars, as if to say this is normal and we can make your experience ‘cute.' 

And yes, it’s true that girls do need products that support their unique needs experiencing puberty at this young age. But it is not enough to unquestioningly meet a consumer need—we need to look at the underlying factors that are pushing our girls into puberty earlier than ever before, and we need to figure out how to support and protect these girls far beyond giving them the Hello Kitty equivalent of period products.

Canaries in the Coal Mine: What is Causing Early Puberty?

While many doctors chalk the declining age of puberty up to a “new normal,” and dismiss that it is a problem for most girls. In fact, there’s a tension between those who are normalizing it, and saying for most girls it is not representative of a medical problem, and those like myself who feel that the increasing prevalence  of early puberty, and at such a young age, should be garnering significant attention from physicians and policy makers, if not all out raising alarm bells: it is a troubling sign that something is affecting our daughters’ endocrine (hormonal) systems. 

Even as recently as a decade ago, if you were to ask pediatricians why there's an early puberty epidemic, if they were even aware of the problem, most would probably shrug and say, “We just don't know why…” I know,  because I asked!  But gradually, research has identified three main explanations for the trend: greater exposure to endocrine-disrupting chemicals; high levels of stress; and increasing rates of obesity. There are also some underlying medical problems that can cause early puberty, such as congenital adrenal hyperplasia, disorders of the gonads—ovaries in girls, testes in boys – or adrenal glands, McCune-Albright syndrome, or hormone-secreting tumors, but these are exceptionally rare

The same factors that are causing increased hormonal and metabolic problems in adult women are, not surprisingly, showing up in our children’s health. Our daughters (and our sons, too) are unwittingly the canaries in our social and ecological coal mine. They are getting “hormonally hot-housed.” And while this is happening in all populations, Black and Latina girls are at highest risk of developing premature puberty, and are at higher risks of all the related medical complications and social ramifications. This is an economic, ecological, and racial and racial justice issue as well.

Let’s look at the three most common underlying factors associated with the early onset of puberty. 

Exposure to endocrine disrupting chemicals (EDCs):

EDCs are agricultural, industrial, and other chemicals that mimic estrogen (and other hormones) in the body, and, as such, are associated with a broad range of hormonal and gynecologic conditions including early puberty, PCOS, endometriosis, fertility problems, metabolic problems, obesity, thyroid problems, reproductive cancers, and more. Numerous EDCs wend their way into our bodies on a daily basis from the time we're conceived and throughout our reproductive lives and accumulate over time. They are in our air, soil, and water, and are used in flame retardant fabrics, cosmetics, plastics, pesticides, detergents and other common household and industrial products.

It doesn’t take much exposure to EDCs to cause health effects. It’s very difficult to prove a causal effect of individual EDCs on the timing of puberty, since all of us have constant low-level exposures to a mixture of these kinds of chemicals. But studies have found associations between early puberty and a range of EDCs, including Bisphenol A  (BPA), DDT, and phthalates. For example, a 2012 study supported by the CDC linked a solvent used in some mothballs and solid blocks of toilet bowl deodorizers and air fresheners to earlier menstruation – they also found it in the bodies of nearly all the people tested in the U.S. Interestingly, some EDCs are also associated with a later age of puberty or delayed menarche – or with an earlier onset of puberty but slower progression through all the stages. Researchers suggest that these chemicals may have differing effects depending on the exact timing of the exposure – whether it’s during the prenatal period, infancy, early childhood, or right before puberty.

Let’s turn our attention to stress. Stress itself can act as an endocrine disruptor. Puberty typically begins in girls when the pituitary gland starts secreting hormones known as gonadotropins, which, in turn, cause the ovaries to grow and to produce estrogen. At the same time, they undergo a parallel process called adrenarche – or the awakening of the adrenal gland – which provokes the development of pubic and underarm hair and underarm odor. It’s thought that higher cortisol levels from chronic stress may trigger the premature activation of the pituitary and adrenal glands. 

Girls are suffering from stress starting at earlier ages than ever. Inadequate sleep, school pressures, stress at home, peer pressure, social media, sexual assault, and bullying are just a few of the major stressors to which our girls are regularly exposed, which have increased in the past decade, some of which increased further during the height of the COVID-19 pandemic, and may have an impact on the timing of the onset of puberty.

Now we’re going to talk about something controversial: Obesity. I want to make something abundantly clear at the outset of this discussion: I firmly encourage body positivity, I do not support fat shaming, and I do not abide by cultural standards around thinness in my medical practice or any of my work with women and children. We can be healthy in a wide range of weights. But rates of early puberty have risen alongside rising obesity rates. About 20% or more of US kids are obese – which is medically different from being overweight – and the rate has tripled in the past 30 years. It was further worsened by the COVID pandemic. Body fat is thought to promote early puberty because fat tissue releases a hormone called leptin, which is necessary for the pituitary gland to begin producing gonadotropins. (That’s the reason some very thin girls and women don’t menstruate: they don’t have enough fat tissue to make leptin.) 

It’s difficult to separate out the role obesity plays in early puberty from the role of EDCs and stress, because exposure to EDCs and chronic stress are themselves risk factors for obesity. And there are some vicious cycles at play: Because EDCs are stored in fat, they may pose even more of a problem for overweight girls. And at the same time that stress can make us fatter, being fat-shamed for being overweight is itself very stressful.

It’s important to avoid making our daughters self-conscious about their weight while teaching them about best food choices, healthy serving sizes, and the importance of getting exercise. We can teach our daughters the healthiest possible habits from their earliest years without giving them food phobias and eating disorders! This means walking our talk – by modeling these habits ourselves – and focusing on the habits themselves, not fixating on body weight or fat. 

So what explains the spike in early puberty during the COVID pandemic? The reasons remain unclear but speculatively include greater stress, an increase in sedentary lifestyles leading to weight gain in children during ‘lockdown,' and an increase in the use of electronic devices. Screen time may be either an independent risk factor or possibly related to its association with increased sedentary behavior. It could also have an effect by disrupting sleep and circadian rhythms; a drop in melatonin activates an increase in a protein called kisspeptin, which is one of the triggers for puberty. 

As parents, we need to be aware of these trends – because even if your daughter isn’t showing signs of early puberty, she may still be exposed to the factors that cause it and that can affect her hormones in other ways. For example, endocrine disruption can increase our daughters’ risk of developing hormonally related cancers later in life.

Why is Early Puberty a Concern?

On a population level, the declining age of puberty is an indication of troubling trends in our environments – and not something I think should be normalized. But does that mean that if an individual girl enters puberty earlier than the average, it’s necessarily cause for concern? That’s more complicated.

Certainly, having your period in second grade, or your breasts develop in kindergarten, well before most of your peers, really sucks for all of the obvious social and emotional reasons. And studies have linked early puberty to a wide range of health risks later in life, including obesity, type-2 diabetes, breast cancer, anxiety, depression, and eating disorders. It also increases a girl’s risk of sexual harassment and abuse, early sexual involvement, and risk-taking behaviors. A girl who is physically more mature might be seen as, and potentially act, more sexually mature than she actually is psychologically and emotionally.

But it’s hard to disentangle whether these risks are caused by early puberty itself or from the stigma – and, often, unwelcome sexual attention – that comes with it. As pediatric endocrinologist Louise Greenspan said in a recent piece in The New Yorker, “We know that people who have menarche earlier do tend to have a higher rate of depression. But we don’t know if that’s a biological thing or a social thing. Is it the biological effects of estrogen on the developing brain? Or is it the stress of looking older than your peers, and having to deal with that?” 

I also want to emphasize that not all scientists feel that the data on earlier ages for puberty are completely accurate, and some also caution ‘doomsdaying.” While I feel that there’s enough evidence to warrant concern and more diligent research, I do agree that we don’t want to panic our daughters. The important thing is to do what we can to take appropriate steps to support and protect our girls should they show signs of early puberty, and to mitigate risks of early puberty as part of an overall healthy lifestyle, as I’ll discuss.

Detecting Early Puberty in Our Girls

It should be noted that the age of puberty has always been fairly variable across individual girls. A girl may be entirely hormonally healthy and begin to show puberty younger than the historically typical 9 years and beyond. The age at which we enter puberty may be what matrilineally heritable – our age of puberty is often similar to our mother’s or maternal grandmother’s – though not always. 

But when the following normal signs of puberty occur younger than 8, it may be a sign of early puberty:

• Height greater than most of their peers
• The appearance of underarm and pubic hair (called adrenarche)
• Underarm odor
• Breast development
• Early menstruation, which typically occurs 2 to 3 years after the above signs

Should a girl experience these signs, even prior to the onset of menstruation, simple tests can be done to determine whether in fact, she is entering puberty, including blood tests to measure sex hormone (estrogen, testosterone, progesterone) levels and X-rays to estimate “bone age,” which is important to measure because one of the risks of early puberty is the early cessation of bone growth, limiting potential height. 

While there are no safe, effective natural therapies that I know that can reverse early puberty, it may be appropriate to halt early puberty with puberty blocking medication  to prevent bone growth and other physical consequences, while allowing our girls time to mature in other ways, something to discuss with your child’s doctor.

Steps You Can Take to Help Prevent Early Puberty

While government agencies, medical organizations, and industry need to tackle the factors contributing to early puberty on a global scale, we can – and must – help prevent or mitigate the factors that can lead to early puberty through the choices we make, and teach our daughters to make. 

Here’s an overview of actionable steps you can take at home.

Prevent Exposure to “Environmental Estrogens”

• Avoid flame retardant products
• Encourage your pre-girls to avoid cosmetics, and if they are going to use them, go natural. It’s more expensive in the short run, but the health price tag is much lower over time! See the Environmental Working Group's Skin Deep website for information on safe cosmetic options.
• Get your daughter a glass water bottle – Life Factory makes them in bright colors, a variety of sizes, with plain and even “sippy” and “straw” tops, and they are dishwasher safe and virtually indestructible. All my daughters have one. Encourage her to avoid drinking out of plastic bottles whenever possible.
• Avoid plastic wrapped foods and plastic food containers for reheating and storing hot foods as much as possible.
• Eat organic whenever possible, especially dairy and meat products, which accumulate environmental contaminants and are more likely to accumulate hormones and antibiotics used in the production process. See the Environmental Working Group's  “dirty dozen” for the “must avoid” if not organic list.
• Switch to using ecologically friendly cleaning products at home, especially using products that are unscented. Even breathing in the scents, which often contain phthalates, can cause endocrine disruption.

Stress-Proof Your Daughter

• Teach your daughter to get help from a teacher and to come to you if there are peer stressors at school or bullying.
• Encourage your daughter to join a school or after school sport, dance class, or other physical activity which is enjoyable for her  – girls who participate in sports are more likely to graduate high school, go to college, avoid drug use, and are less likely to experience a teen pregnancy. 
• Reduce exposure to TV violence and shows which sexualize and objectify girls and women. 
• Reduce social media exposure, and teach your daughter how to engage with social media in a more healthy way, to avoid ‘FOMO,’ ‘compare and despair,’ unrealistic body images, and the anxiety and depression we know has risen commensurate with our girls’ use of social media platforms. 
• Teach simple meditation or relaxation skills to be done before bedtime, exams, or in a stressful situation. Simply breathing in and saying, “I am” on the inhale, and “At peace” on the exhale 4 times in a row, or “counting to 10” with deep breathing can make a difference!
• Learn about and teach resilience tools to your daughter – it’s a gift that will last a lifetime!

Encourage Healthy Eating and Exercise

• Encourage healthy eating as part of a healthy lifestyle so we’re not stigmatizing food. Remember, we’re up against a behemoth food industry that wants to addict our kids to sugar and processed foods from the earliest ages – let’s teach our kids to recognize this and make healthy choices. 
• Cut out soda (and even fruit juice which can have as much sugar as a soda!). Water is the healthiest beverage.
• Emphasize a plant-based, whole foods diet, with healthy portion sizes without being restrictive or stigmatizing about food. 
• Do your best to reduce white bread, white pasta, and white rice, and processed foods, from the diet: instead emphasize good quality proteins and vegetables as the mainstay of their diets, with healthy ‘treat’ options to choose from 
• Reduce the amount of TV watching by half – and adding exercise will optimize the benefits of this by getting our kids moving more! 
• Make sure you’re doing all of these things yourself – our kids model what they see far more than what we say!

Prevent Stigma: Teach Your Daughter About Her Body and Her Health

We must prevent stigma and teach our daughters to respect and love their bodies. If your daughter is entering puberty much earlier than her peers for whatever reason, it’s all the more important to talk with her about what's going on and help her feel comfortable in her changing body and self-perception. It’s critical to not stigmatize, pathologize, or in any way contribute to a sense of being ‘abnormal,’ including when it comes to medical visits and assessments for early puberty if those are needed. And while the social consequences should not be dismissed, and need to be addressed for her health and safety,  it’s simultaneously  important not to introduce or exacerbate social anxiety or fear. 

We have to take the stigma out of puberty so we can talk openly with our daughters and help them feel confident in their bodies no matter what their age. Let's start talking with our daughters today, asking them questions about how they’re feeling and what they’re going through – and taking care of ourselves in ways that model self love, self care, and best health – so that they can emerge into womanhood confident and without the preventable risks of long term emotional and health problems that in some cases, though not all, can be associated with early puberty, or just being female in our culture.