Unusual physical development in young children may signal underlying medical conditions. Joan Chew reports
When she was five years old, Agnes (not her real name) started developing breasts and towering over her peers.
When signs of puberty appear before age seven or eight for girls and nine for boys, it is known as precocious puberty.
For Agnes, her condition was caused by an injury to the brain, said her doctor, Associate Professor Fabian Yap, a senior consultant and the head of the endocrinology service at the department of paediatrics at KK Women’s and Children’s Hospital (KKH). She had suffered a blow to her head which led to bleeding in the brain.
However, in some cases, it is not known what triggers this premature release of hormones.
A recent study in the United States found that girls are more likely today than in the past to start developing breasts by age seven or eight. Researchers suspect that higher obesity rates are largely responsible.
Doctors interviewed here say they have noticed an increase in the number of cases of precocious puberty over the past decade, The Straits Times reported last week.
Other than obesity, the condition could be a symptom of an underlying medical condition in the brain or reproductive system.
Although puberty is deemed precocious in girls if it begins before seven or eight years of age, in some cases, girls aged six or seven who begin to develop breasts may simply be experiencing early normal puberty, Prof Yap said.
To determine if there should be medical intervention, Prof Yap said that tests to track the hormonal levels in the child may be conducted.
Boys tend not to have this grey zone. Those whose testicles develop before nine are said to be experiencing precocious puberty. Prof Yap said that this is because there is greater variability in girls when it comes to puberty – but the reasons are not known.
Precocious puberty is rare here. KKH identifies fewer than 10 new cases a year, said Prof Yap.
When parents should worry In some cases, the early onset of puberty is considered normal. An example is premature adrenarche, whose symptoms include isolated pubic or axillary (armpit) hair in boys and girls, said Associate Professor Lee Yung Seng, a senior consultant in paediatric endocrinology at the University Children’s Medical Institute at National University Hospital.
Two types of precocious puberty are of concern – central and peripheral.
■ Central: The brain is triggered into starting puberty and this is sometimes caused by brain tumours or brain injuries from trauma or infections.
Prof Yap estimated that KKH has given treatment to suppress puberty in about 20 to 30 children who had central precocious puberty in the past 13 years. He believes that the number is higher for those without a known cause.
Prof Lee estimated that more than 90 per cent of girls with this type of precocious puberty have no underlying medical problem.
However, boys with the condition are more likely to have medical problems such as brain tumours or brain injuries at its root, he noted.
Medication can be used to control the production of sex hormones. Prof Yap prescribed such medication to Agnes, who took it until she turned 13 this
■ Peripheral: This is caused by the over-production of sex hormones – oestrogen and testosterone – due to problems with the ovaries, testicles or adrenal glands.
It can also be caused by exposure to external sources of sex hormones such as creams.
Prof Lee noted that the peripheral type is even more rare than the central type.
He added that in girls, this may be associated with ovarian cysts or tumours.
Treatment will target the cause of the disorder.
With early puberty, there are concerns that a young girl is mentally and emotionally immature to handle menstruation.
Dr Vera Oh, a paediatrician at Mount Elizabeth Medical Centre, said that for girls who have suffered some form of brain damage and already need help with their daily activities, coping with their early periods would place a greater strain on their caregivers.