One day your seven-year-old is asking for bedtime stories and playing with dolls.
A few months later, she’s suddenly much taller than her classmates, needing her first bra and asking why her body looks different from everyone else’s.
For some families, childhood seems to speed up overnight.
As a paediatric endocrinologist, one of the most common concerns I hear is: “Is my daughter growing up too early?”
While every child develops at their own pace, puberty that starts much earlier than expected deserves medical attention.
The reassuring news is that, for some children, we can safely press the “pause” button on puberty, giving them more time to grow, learn and enjoy being a child before continuing through puberty at a more appropriate age.
What is precocious puberty?
Puberty is the body’s natural journey from childhood to adulthood.
In girls, it usually begins between eight and 13 years of age.
The first visible sign is breast development, followed by a growth spurt, and later, the start of menstruation.
When breast development begins before the age of eight years, it is called precocious puberty.
Some girls may also develop pubic hair or body odour early.
These changes alone do not always mean true puberty has started, so it is important to have your child assessed rather than assuming puberty has begun.
When I see a girl with possible precocious puberty, I begin by asking how quickly the changes have happened and reviewing her growth over the past year.
Children with rapidly progressing puberty often grow much faster than expected.
We also perform blood tests to determine whether the hormones controlling puberty have been activated.
One of the most useful investigations is a bone age X-ray.
This is a simple X-ray of the left hand and wrist that shows how mature the bones are compared with the child’s actual age.
This is important because oestrogen speeds up bone maturation.
Although girls with early puberty are often taller than their classmates initially, their growth plates may also close earlier.
Without treatment, some girls may stop growing sooner than expected and lose some of their potential adult height.
Why does it happen?
The most common type is called central precocious puberty (CPP).
Think of puberty as being controlled by a “master switch” in the brain.
The hypothalamus and pituitary gland release hormones that tell the ovaries to produce oestrogen, starting puberty.
In children with CPP, this switch turns on earlier than it should.
The first question many parents ask is: “Did we do something to cause this?”
The answer is almost always no.
In most girls, we never find a specific reason why puberty started early.
Doctors call this idiopathic CPP, meaning there is no identifiable underlying cause.
We do know that genetics and obesity is associated with earlier puberty in girls.
Girls with a family history of early puberty and excess body weight are more likely to enter puberty earlier than their peers.
However, not every girl with obesity develops precocious puberty, and many girls with precocious puberty are not overweight.
Weight is only one of several factors that may influence the timing of puberty.
Parents also frequently ask whether chemicals in food or the environment are responsible.
Researchers have been studying endocrine disruptors – chemicals that may interfere with the body’s hormone system.
Examples include bisphenol A (BPA), previously found in some plastic food containers and bottles; phthalates, which may be present in some plastics and personal care products; and certain pesticides.
While some studies suggest these chemicals could influence the timing of puberty, the evidence is not strong enough to conclude that they directly cause precocious puberty and more research is needed.
In a small proportion of children, however, early puberty is caused by an underlying condition affecting the brain or pituitary gland.
This is more likely in very young girls, especially those younger than six years, or in children who have neurological symptoms such as persistent headaches, changes in vision or seizures.
In these situations, we usually recommend an MRI (magnetic resonance imaging) scan of the brain and pituitary gland to look for an underlying cause.
A much rarer type is called peripheral precocious puberty, where oestrogen is produced by the ovaries, adrenal glands or another source without the brain switching on puberty.
The causes and treatment are different, but fortunately, this form is uncommon.
Chloe’s story
Chloe was seven years old when her parents brought her to see me.
Over just a period of six months, they had noticed breast development and a rapid growth spurt with Chloe becoming noticeably taller than her classmates.
Although she still loved dolls and playground games, she was becoming increasingly self-conscious about her changing body.
Her blood tests confirmed CPP, and her bone age was 10 years, more than two years ahead of her actual age.
When we discussed the results, we talked about much more than numbers.
Because Chloe’s bones were maturing quickly, she was at risk of losing some of her future adult height.
Her parents were equally concerned about the emotional impact.
Chloe was beginning to feel different from her friends and could potentially start menstruating while still in lower primary school.
After discussing the benefits and limitations of treatment, her family decided to begin puberty suppression with a long-acting injection given once every three months.
For them, the goal was not simply to help preserve height.
It was to give Chloe more time to grow emotionally before her body continued its journey through puberty.
Is treatment always necessary?
One of the most important parts of my job is helping families decide whether treatment is actually necessary.
Not every girl with precocious puberty needs to have puberty paused.
Some girls have slowly-progressing puberty that causes little impact on their growth or predicted adult height.
Others are coping well emotionally and may be closer to the normal age range for puberty.
In these situations, careful monitoring with regular clinic visits, growth measurements and occasional repeat investigations may be all that is needed.
On the other hand, treatment is more likely to be recommended for younger girls – those whose puberty is progressing rapidly, those with significantly advanced bone age, or when early puberty is likely to have a major impact on adult height or emotional well-being.
Every child is different.
The decision to start treatment should be made together with a paediatric endocrinologist, taking into account the child’s age, the speed of puberty, growth pattern, bone age, predicted adult height and emotional well-being.
The goal is not simply to delay puberty, but to choose the approach that is best for that individual child.
How do we ‘pause’ puberty?
The treatment works by temporarily switching off the hormones that drive puberty.
Normally, the brain sends signals to the ovaries to produce oestrogen.
The medicines we use, called gonadotrophin-releasing hormone (GnRH) agonists, interrupt this process, allowing oestrogen levels to return to pre-pubertal levels.
As a result, puberty pauses.
Think of it as pressing the pause button on a movie.
The story has not ended; it simply waits until the timing is right to continue.
Most children receive an injection every one, three or six months, depending on the medication used.
Within a few months, breast development usually stops progressing and may even become slightly less noticeable.
Growth slows back to a normal childhood rate, bone maturation slows, and menstruation is prevented if it has not already started.
These medications have been used safely around the world for years and are the standard treatment for progressive CPP.
Like all medicines, however, they can have side effects.
Fortunately, these are usually mild.
The most common are pain, redness or swelling where the injection is given.
Some girls experience a small amount of withdrawal vaginal bleed during the first few weeks of treatment, but this usually settles on its own.
Serious side effects are uncommon.
Importantly, treatment does not affect future fertility.
The injections are usually stopped when the child reaches a more appropriate age for puberty, usually around 10 years old.
Depending on her growth, bone age and emotional readiness, the brain naturally restarts puberty over the following months.
Children continue to attend regular follow-up visits so their doctor can monitor growth and bone age, and ensure treatment remains appropriate.
Remember, puberty should not be suppressed beyond the normal age range as well.
When should parents seek help?
Consult a paediatric endocrinologist if your daughter has:
- Progressive breast development before the age of eight years.
- Rapid height gain over a short period.
- Several signs of puberty developing together.
- Vaginal bleeding or menstruation before the age of 10 years.
Remember that early assessment does not automatically mean treatment.
Some girls simply need reassurance and careful monitoring, while others do benefit from puberty suppression.
The earlier we assess a child, the more options we have to support both her physical growth and emotional well-being.
Childhood only comes once, and sometimes, giving it a little more time is the greatest gift of all.
Dr Jeanne Wong Sze Lyn is a consultant paediatrician and paediatric endocrinologist. For more information, email starhealth@thestar.com.my. The information provided is for educational purposes only and should not be considered as medical advice. The Star does not give any warranty on accuracy, completeness, functionality, usefulness or other assurances as to the content appearing in this column. The Star disclaims all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.
