SINGAPORE - Q My daughter is 14 years old this year. She had her first menstruation six months ago, but has had none since then.
Is this normal for a teenage girl?
A Puberty is a stage of life that every girl goes through on the way from adolescence to young adulthood.
In response to changes in hormone levels, the maturing body goes through a series of changes that prepares it for the making and carrying of babies.
These physical changes are accompanied by mood and psychological changes and can make the adolescent years quite challenging for both the child and parents.
In girls, the first of these changes is the development of breast tissue, known as thelarche, which usually begins at around 10 years old.
This is followed by the development of other secondary sexual characteristics, such as pubic hair and changes in body shape.
In many cultures, the onset of menstruation, known as menarche, marks the point at which a girl is recognised as having reached womanhood.
This usually occurs around two or three years after thelarche, although there is some individual variation.
In this respect, your daughter is perfectly normal in starting to menstruate at the age of 14.
Progress of puberty is monitored in routine check-ups by the School Health Service, run by the Health Promotion Board. It refers children who are progressing significantly faster or slower than expected to doctors for further evaluation.
BODY IN TRANSITION
Maturation of the reproductive system is a gradual process. In the initial period, there may be imperfect coordination between the glands responsible for producing the hormones which regulate the menstrual cycle, much like members of a new team who are learning to work together.
This can result in wide variations in menstrual cycle lengths during the first few years after the onset of menstruation, much like what you have described in your daughter's case.
Oligomenorrhoea - infrequent menstruation that occurs with intervals of more than 35 days - is frequently observed during this period. It was reported in 38 per cent of Asian adolescents in a World Health Organisation study.
In most girls, the pattern can be expected to normalise within one or two years.
Again, in this respect, your daughter's menstrual pattern is not a cause for alarm and she is likely to be in the transition phase to a normal menstrual cycle.
Less common causes of oligomenorrhoea in adolescents include caloric deprivation, when the child is undernourished because of chronic illness or eating disorders; polycystic ovarian syndrome, a common hormonal disorder in women of reproductive age that results in irregular menstruation, excessive hair growth and acne; or other rare medical and genetic disorders.
If your daughter has signs of abnormal pubertal development or if you suspect that she may have an eating disorder, then a visit to the gynaecologist is recommended.
The gynaecologist will assess her progress of puberty and may do a series of tests to assess her hormonal levels and look for other causes of an abnormal menstrual cycle.
Dr Cindy Pang, consultant at the department of obstetrics and gynaecology at the Singapore General Hospital.
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