Early puberty is a concern for many parents. If girls show any signs of secondary sexual development before the age of 8, and boys before the age of 9, they may be experiencing precocious puberty. Research has indicated that individuals with early puberty have a higher chance of developing breast cancer and uterine hyperplasia in the future compared to the general population. Hong Kong paediatric specialist Dr. Tsui Tsz-kwan stated in an interview that there are many causes of early puberty. In one case, a 5-year-old girl sought medical attention due to pain in one breast. After multiple examinations, her physical condition was found to be normal, and it was later discovered that environmental factors might have been the cause.
What is precocious puberty? Dr. Xu Ziyun states that when children enter puberty, their hormone levels increase, leading to a series of physiological and psychological changes. Precocious puberty is defined as the appearance of puberty and secondary sexual characteristics earlier than the normal average age.
Generally, the normal age of puberty development for boys is between 9 and 14 years old, and for girls, it is between 8 and 13 years old. If a boy develops secondary sexual characteristics before the age of 9, or a girl before the age of 8, there is a chance of precocious puberty.
▲ If a boy's testicles exceed 4ml in volume, it signifies the onset of puberty and the beginning of development. The image shows a testicle volume measurement device. (Photo by Li Ji-jian)
In boys, testicles larger than 4ml indicate the onset of puberty and development. For girls, the first sign is breast development, which can be unilateral or bilateral, and may be accompanied by tenderness and discomfort.
Dr. Xu recalled that a little girl, just over five years old, came for a consultation because of pain in one of her breasts for over a month. Upon examination, breast tissue was found, which appeared to be premature breast development.
However, after the girl underwent blood tests and X-rays, all results came back normal. Dr. Xu then spoke further with the parents and discovered the girl might have been affected by environmental factors – it turned out the girl's family used many plastic dishes and toys, and the family also had a habit of using aromatherapy.
After learning about the child's lifestyle habits, the parents began to make further adjustments. These included reducing snack consumption, opting for healthier foods, and using fewer plastic products and essential oil diffusers. Three months later, during a follow-up appointment, it was discovered that the child's unilateral breast had shrunk by almost two-thirds. Dr. Xu estimated that the girl had unilateral precocious puberty, which was very likely caused by environmental factors.
Brain tumours and genetic mutations can cause precocious puberty
There are many causes of precocious puberty. Dr. Xu explains that medically speaking, precocious puberty is divided into "central precocious puberty" and "peripheral precocious puberty".
Central precocious puberty involves the pituitary gland secreting developmental hormones prematurely, which in turn stimulates the gonads, including the testicles and ovaries, to release oestrogen and testosterone, leading to the appearance of a child's secondary sexual characteristics. Generally, this condition is more common in girls, with nearly 80-90% of girls experiencing idiopathic precocious puberty, meaning there is no specific underlying cause.
Conversely, most boys have pathological factors, including brain tumours, serious brain diseases, or have suffered from inflammation, genetic mutations, etc., which lead to precocious puberty.
As for "peripheral precocious puberty", it refers to peripheral organs releasing androgens or estrogens, as well as cortisol, prematurely due to unknown reasons, leading to precocious puberty.
The underlying causes may be related to endocrine problems such as hypothyroidism, adrenal gland issues, or even ovarian or testicular abnormalities, or cysts and tumours. It is generally unrelated to pituitary developmental hormones.
Dr. Xu stated that apart from certain pathological factors such as cysts or tumours, environmental, genetic, and dietary factors, among others, can also be potential triggers for precocious puberty.
Dr. Xu stated that for children to develop normally, a balanced diet is essential. When parents select food, they should pay attention to avoiding too many snacks or processed foods, and try to choose foods that are hormone-free and certified. Adequate sleep and appropriate exercise can also aid in children's normal development. If a child experiences precocious puberty, they should seek medical advice as soon as possible.
