Delayed puberty may seem like a very specialist area of paediatrics, but it’s actually a relatively common reason for presentation to the GP, and a lot of children are referred onwards into paediatric clinics. It can also be a sign of serious underlying conditions, which are important not to miss!

This article is designed to be an introduction to delayed puberty, to help you out if you’re working in a GP practice, or acute paediatrics, and parents/ young people raise concerns about a delay in puberty.

So, when is it normal for a child to go through puberty?

For girls, puberty normally starts between the ages of 8 and 13. For boys, it’s 9 and 14.

In girls, the first sign of puberty is development of breast buds. In boys, the first sign of puberty is testicular enlargement.

Other pubertal changes follow on from this. In girls, this includes breast enlargement, a growth spurt, development of axillary and pubic hair, and menstruation.

In boys, this includes ongoing enlargement of the testicles and penis, a deeper voice, development of axillary and pubic hair, and a growth spurt.

Usually, puberty takes a maximum of 5 years to complete.

When would we say puberty is delayed?

Essentially, puberty is delayed in a girl if she doesn’t develop breast-buds by 13. Puberty could also be considered to be delayed if a girl hasn’t started her periods by the age of 14. Puberty is delayed in a boy if his testicles haven’t started to enlarge (more than 4ml is the cut-off), by the time he’s 14.

If puberty isn’t complete within 5 years, this would also raise concerns of delayed or arrested puberty.

So how do children with delayed puberty present?

Sometimes, they present with concerns regarding a lack of pubertal changes – for example, a girl who doesn’t need a bra when all her friends do. However, it’s also common for children to present with concerns regarding short stature, as they haven’t yet had their pubertal growth spurt.

What causes delayed puberty?

To understand the causes of delayed puberty, it helps to understand a little bit about the underlying changes that drive the process of puberty.

GnRH is produced in the hypothalamus. This stimulates the pituitary gland to produce LH and FSH, which in turn stimulate the ovaries/testicles to produce oestrogen/ androgens like testosterone.

If the problem is at the level of the pituitary, we refer to it as hypogonadotrophic hypogonadism – i.e the gonadotrophins (LH and FSH) are low, and that’s the underlying cause behind the low oestrogen/testosterone, and the resulting lack of pubertal changes.

Causes of hypogonadotrophic hypogonadism include Kallman syndrome, or brain tumours, such as craniopharyngiomas.

Hypogonadotrophic hypogonadism

If the problem is at the level of the ovaries/testes, we refer to it as hypergonadotrophic hypogonadism – i.e the pituitary works, and it’s making plenty of LH and FSH, but the ovaries/testicles aren’t able to respond, meaning the oestrogen/testosterone levels are still low, and pubertal changes aren’t present. Causes of hypergonadotrophic hypogonadism include complications from surgery/radiotherapy/ infection, and genetic conditions such as Turner’s syndrome in girls, or Klinefelter’s syndrome in boys.

Hypergonadotrophic hypogonadism

Constitutional Delay

All that being said… none of these are actually the commonest reasons for a delay in puberty.

The commonest reason for delayed puberty overall (although it is more common on boys than girls) is a constitutional delay in growth and puberty – essentially, being a late bloomer. This often runs in families.

Functional Delay

The second most common reason is functional hypogonadotrophic hypogonadism (this is more common in girls than boys).

All this really means is that the LH and FSH levels are low, but not because there’s an issue with the pituitary. In chronic disease, or malnutrition, the body is under too much stress to initiate puberty. This is normally temporary, and if the underlying cause is addressed, puberty will progress in a normal way. Conditions that can cause this picture include eating disorders, thyroid disease, and coeliac disease. The same picture can be seen in children who are very active, and don’t have a sufficient intake – commonly swimmers, dancers, and gymnasts.

How should we assess a child presenting with delayed puberty?

History

When thinking about the important questions to ask in the history, it’s important to ask about the symptoms of puberty, but also symptoms that may give you the clue to the underlying cause of any delay you’ve identified.

HPC– Have the parents or young person noticed any of the pubertal changes described above? (Be careful with this – changes such as acne/ pubic & axillary hair/ body odour are driven by the adrenals, and don’t indicate true puberty unless accompanied by breast bud development/ testicular enlargement)

Are there any symptoms suggestive of thyroid issues (change in bowel habit/ temperature perception/skin/hair/energy/mood)? Are there any other symptoms of chronic disease? Has there been a recent change in eating patterns or exercise routines?

Are there any symptoms to suggest an underlying brain tumour (headaches/ personality change/ visual symptoms)?

Does the patient have anosmia (this would suggest Kallman syndrome)?

PMH– Any previous malignancy/radiotherapy/surgery/torsion?

Any previous issues with disordered eating?

Any known cardiac conditions that may have been treated as a baby? (Turner’s syndrome is associated with several cardiac conditions, including coarctation of the aorta)

Family History– When did parents and siblings go through puberty? Any FH of malignancy?

Social History– Impact on the young person – feeling like you’re out of sync with your peers can be very difficult for teenagers, and can lead to bullying

Issues in school – e.g. learning disability, if recent, this could indicate underlying disease. If long-term, this could be associated with a syndrome, such as Turner’s or Klinefelter’s

Examination

Tanner staging can be useful as an objective description of your examination findings, and to clearly document the stage of puberty a young person is at.

Also look for any features that might indicate one of the underlying chronic diseases previously discussed, or a genetic syndromes. Always examine visual fields as a craniopharyngioma can present with asymptomatic bitemporal hemianopia.  

What investigations might be useful?

In terms of investigations, the initial approach should be to investigate for any underlying chronic disease.

To do this, bloods including a FBC, U&Es, LFTs, TFTs, anti-TTG, and an ESR would be helpful.

If these are all normal, and the criteria for delayed puberty is met, you’ll be starting to think about referral.

If possible, it’s really helpful for patients to have an FSH, LH, testosterone, oestradiol, and prolactin measured, prior to being seen in clinic.

In addition to this, a bone age x-ray can be really helpful, as bone age correlates better with timing of puberty than chronological age (bone age is measured using an x-ray of the left wirst). However, not everyone in primary care / general paediatrics has access to bone age x-rays, and this shouldn’t delay referral. Similarly, a karyotype can be really useful, to identify Turner’s or Klinefelter’s, but this isn’t always accessible to those working in primary care.

How is delayed puberty managed?

As previously alluded to, if this case meets the definition of delayed puberty, and you haven’t identified a reversible cause on initial testing, this is the time to refer to a paediatrician with a special interest in endocrinology. If you think puberty has started, but then stopped – arrested puberty – this is a red flag, as this can be caused by a brain tumour, and the referral should be urgent.

References

Tang C, Zafar Gondal A, Damian M. Delayed Puberty. In: StatPearls [Internet]. Available from: https://www.ncbi.nlm.nih.gov/books/NBK544322/

Mushtaq T, Howard S. Delayed puberty. In: BMJ Best Practice. Available from

https://bestpractice.bmj.com/topics/en-gb/1126

Wray E, Wood C. Delayed puberty. In: Healthier Together. Available from https://nenc-healthiertogether.nhs.uk/professionals/paediatric-pathways

Image references

Tanner Staging diagram taken from BMJ – as per reference below image

Written by Lily Wray, Paediatric ST1 in Newcastle Upon Tyne,

Edited by Dr Bex Evans, Paediatric Registrar