How Early Is Too Early for a Girl to Enter Puberty?

From the WebMD Archives

Oct. 24, 2000 -- Jasmine turns 7 next week, but she already has many physical features that people associate with girls closer to their teen years. Ever since she turned 4, Jasmine has surprised her parents with subtle signs of what doctors call precocious puberty. "It scared me to death," says Traci Henderson, her mother.

Precocious puberty, also called early puberty, is a medical condition that doctors have long recognized. It is five or six times more common in girls than boys. But these days, even girls without this condition are entering puberty earlier than their mothers and grandmothers did, often developing breasts and pubic hair several years earlier than what was previously considered the norm.

In years past, girls typically began puberty at age 10 or 11. But a study published three years ago in the journal Pediatrics suggested that it's now normal for girls of 7 (if they're African-American) or 8 (if they're white) to have breast and pubic hair development.

"There is pretty compelling evidence that girls are maturing earlier than in the past," says Paul Kaplowitz, MD, PhD, a pediatric endocrinologist at Virginia Commonwealth University School of Medicine in Charlottesville.

But just how early is too early? If a child shows signs of puberty before age 6 (in African-American girls) or 7 (in white girls), Kaplowitz advises having the child evaluated by a pediatrician, as she may be entering precocious puberty or have another medical condition. Otherwise, it's likely she's just part of a growing contingent of early bloomers.

Researchers don't completely understand what's causing younger and younger girls to show signs of puberty.

Some researchers think it's hereditary. Others credit chemicals in the environment for the trend, says Kaplowitz. "Some think that residues of pesticides -- DDT, PCBs -- are to blame," he says. These pesticides can break down into compounds that may have estrogenic activity. In the lab, he says, the substances have been shown to interact with estrogen-receptor cells. "But no one has shown a clear connection between that and early puberty," he says.

One thing that's very likely playing a role is the increasing trend toward childhood obesity, Kaplowitz tells WebMD. "It's long been known that very overweight girls tend to mature faster at an earlier age," he says. "Thin girls and athletic girls tend to be on the late side." In a study he's preparing to publish, preliminary data support that view.


In rare cases, early signs of puberty might indicate a central nervous system problem, if accompanied by other symptoms, such as headaches and seizures.

Jasmine's parents rushed her to the pediatrician when they noticed she was developing pubic hair at age 4. "The doctor ran a couple of tests, did a bone scan, measured her bones, did blood work ... [and] determined it was precocious puberty," Henderson says.

Even in many cases in which a girl under 6 shows signs of puberty, there may be no problem, says Kaplowitz. "It's not at all rare to see children 3 and under with breast development. The majority of the time, it's a normal variant ... different from precocious puberty because it doesn't progress rapidly. Growth is normal, and bone maturation does not advance," he says.

But for some girls, like Jasmine, these signs can signal a hormonal imbalance, says her doctor, John Parks, MD, a pediatric endocrinologist at Emory University School of Medicine in Atlanta. Too much estrogen produced by the ovaries triggers rapid increases in breast development, bone growth, weight gain, appetite -- and menstruation follows a few years later.

The current treatment for precocious puberty involves monthly injections of hormone-like substances (one is marketed as Lupron) that suppress the reproductive hormones. "Hormone therapy will stop the progression of breast development," Parks tells WebMD. "It also slows height and weight increases, and the progression of skeletal maturation."

If precocious puberty is not treated, a child could find herself in the throes of emotions and physical changes more typical of teens, Parks tells WebMD. And ultimately, her bone development -- and adult height -- could be affected.

"Early puberty leads to early growth, so that a child tends to be tall relative to their peers," Parks says. "These children will complete their growth early, so they wind up taller than peers in first through fourth grades. Then, they stop growing and wind up shorter than you would expect from family background."

Children who are well into puberty before their age 6 birthdays will benefit from hormonal treatments in terms of their adult height, Parks tells WebMD. "If puberty appears later, or intervention is later, the height issues become a little more cloudy. Most of those children attain quite a normal adult height. The loss might be 1 or 2 inches [from] what you would expect from parents' heights.


"But it's the very, very early developers who stand to lose more with untreated early puberty," he says. "The younger they are, the more they stand to benefit in terms of improvement in adult height."

Jasmine's growth was relatively slow until the past year, so her parents opted to hold off treatments for a while, her mother says. "We didn't want to subject her to monthly injections that could last from her fourth to her 10th birthday -- six years," she says. She's just had her seventh birthday -- and her first injection. Not a fun experience, her mother says. "She's still a little girl. ... She hates needles," she says.

Kaplowitz says that some doctors are overprescribing Lupron to appease anxious parents. "Lupron is wonderful for 4-, 5- and 6-year-olds who are maturing very rapidly," he tells WebMD. "But there are a lot of kids who are 7 to 8 years of age who are receiving this drug and would probably do just fine without it. The drug costs $6,000-10,000 a year, plus you have doctor visits for the monthly injections. Plus, there are visits to the endocrinologist every three months."

But parents worry, too, that early-blooming daughters will get too much attention from older boys. They worry about giving sex education to a 7-year-old. And for many, it's just plain disturbing to see physical signs of puberty in a 4-, 5- or 6-year-old.

"Jasmine is already feeling embarrassed about what's happening to her," Henderson says. "She's the tallest person in her class, ... yet she still acts like a little girl. ... I'm nervous because she has started growing little breasts, and they're noticeable because she's slender and tall. ... Her period must not be very far away."

In fact, it was the thought of her daughter possibly beginning menstruation while just in second grade that convinced Henderson to start the Lupron injections, she tells WebMD. Jasmine will have them until she reaches 10 or so, when many girls start their periods. "Her breasts will disappear," her mother tells WebMD. "We just needed to slow her body down a little."


But Kaplowitz says that trends are showing that, despite the emergence of earlier signs of puberty, girls are generally not starting their menstrual periods any earlier. White girls typically start menstruating at about age 12½, and African-American girls at about age 12.

"That hasn't changed in 50 years," he tells WebMD. "Parents should know that a girl who has started breast development at 7 is not likely to have menstrual period for at least two or three years. We're not talking about breasts one day and period starting the next. There's plenty of time to prepare a young girl for menstrual periods."

Parks adds a note that should reassure even the parents of girls with true precocious puberty. "Early puberty does not seem to increase interest in genital sex -- at least not in girls, to the same extent that male precocity does," he tells WebMD.

For Henderson, it's all been confusing and overwhelming.

"Jasmine still plays with Barbie dolls," she tells WebMD. "How do you explain menstruation to your 7-year-old ... and she has a male teacher? ... How would she handle it at school? I feel better knowing her period won't start."