Paediatric Turner syndrome

Turner syndrome is characterised by gonadal dysgenesis and short stature. The diagnosis is confirmed with the karyotype 45 XO, though mosaicism is common.

Genetic counselling

This should be offered to all patients at, or soon after, diagnosis.

Review baseline pituitary function

If there is any doubt that hypogonadotropic hypogonadism may not be isolated, consider dynamic function testing.

MRI pituitary

If karyotype is apparently normal, then other causes of hypogonadotropic hypogonadism are possible. Thorough investigation should therefore be performed.

Assess bone age in all children presenting with Turner syndrome

Delayed bone age supports the diagnosis of absent puberty. Growth hormone treatment should be considered in those with short stature and delayed bone age. This decision should be undertaken in conjunction with an experienced paediatric endocrinologist.

Consider growth hormone therapy for short stature

In Turner syndrome (TS) and Noonan syndrome (not licensed by the EMEA) growth is improved by treatment with growth hormone if the condition is detected prior to epiphyseal fusion. GH 0.05-0.067mg/kg/day is recommended.

Statural growth should be monitored 6 monthly to determine treatment response, and allow dose titration and to confirm when final height is reached. During treatment, GH dose may be increased within the range above if there is a poor response in growth velocity. Once height stabilises, GH should be stopped unlike paediatric GH deficiency.

Discuss fertility issues at, or soon after, diagnosis

If appropriate, fertility should be discussed early with the patient and their family.

Patients need to understand that successful pubertal induction will not affect or restore fertility, although appropriate uterine development is necessary prior to possible future pregnancies.

Screening required at diagnosis

At confirmation of diagnosis, arrange the following tests in all cases: karyotype analysis, echocardiogram, renal ultrasound scan, pelvic ultrasound scan, bone densitometry scan, thyroid stimulating hormone, free thyroxine, thyroid and coeliac antibody screen, urea and electrolytes, liver function test, bone profile, fasting lipid profile, fasting glucose and HbA1c.

Hormone replacement therapy


Discuss treatment aims, timescales and outcomes

Treatment aims to replicate the natural process of puberty and should occur over approximately the same timescale - approximately two to three years. Breast development and secondary sexual hair should occur. Some bleeding may occur during pubertal induction, at which point, cyclical progesterone should be added.

Patients need to understand that accelerating the treatment may have adverse psychological and physical consequences, for example poor breast development.


Initiate treatment

The timing of estrogen initiation requires careful consideration on an individual case basis. The aim is to replicate natural puberty, without reducing potential gains in height that may be achieved with growth hormone. The decision needs to take into account the level of spontaneous pubertal development, current height, age at diagnosis and the patient wishes regarding GH therapy. Estrogen therapy should generally be started at the physiological age of puberty i.e. around 11 to 12 years. Delay of induction of puberty could have negative effects on uterine growth and secondary sexual characteristics.  

Typical starting dose in an estrogen naive patient is 1.25mcg ethinylestradiol. Increase dose to 2.5mcg, then by 2.5mcg increments every six months to 10mcg. The dose may then increase to 15mcg.

An alternative is to use topical estrogen therapy. This may give a better eventual breast shape, and is well tolerated, with the patches often easier to source in the community than low dose ethinylestradiol. A typical start dose is with one quarter of a 25mcg Estradiol patch given either overnight every day, or left on and replaced every 72 hours. The dose should then increase every 3-4 months to half a patch, then a whole 25mcg patch, then a 50mcg patch, then a 75mcg, then a 100mcg patch.  


Dose titration

Consider pelvic ultrasound scan to assess uterine size at this stage.

Once the patient experiences vaginal bleeding or if the patient has tolerated 15mcg orally, or 100mcg transdermally, consider adding cyclical progesterone. Measurement of LH and FSH levels may also be used to help judge whether the final dose of topic estradiol is sufficient, as some girls will require higher doses.


Alternative treatment regimens

Cyclical estrogen and progesterone replacement therapy should be considered in all patients.

The combined oral contraceptive pill is a convenient preparation and may be more socially acceptable at diagnosis and in young patients. However, there has been some doubt as to whether this offers sufficient bony protection unless taken continuously, with some authorities advising taking this 3 packs at a time. Combined oral contraceptive pills are also contraindicated in patients with a history of migraines with aura. Low dose HRT is more suitable in these cases.

Hormone replacement therapy is more appropriate in the long term, and should be tailored to suit the individual, for example by offering topical, depot or oral preparations. Choice will also depend on the age of the patient, presence or absence of a uterus, and history or family history of breast or endometrial cancer. A history of, or strong risk factors for, cardiovascular or thromboembolic disease will also need to be considered.

Topical estrogen is particularly useful in patients at high cardiovascular risk, or with abnormalities of liver function. Combined patches are available, or if estrogen gel is used, low dose continuous progesterone will also be required to prevent endometrial hyperplasia e.g. 1x350mcg progesterone only pill daily.

Estrogen replacement therapy should be continued until the time of the natural menopause - typically to age 50. Vaginal dryness may be ameliorated by topical estrogen gels.


Duration of treatment

Continue sex hormone replacement therapy until the time of the natural menopause - typically to age 50.


Vaginal gels

Topical estrogen may be beneficial to help vaginal dryness.

Annual follow up

All patients should be offered life long annual follow up. The following tests should be arranged prior to every review: thyroid stimulating hormone, free thyroxine, urea and electrolytes, liver function test, fasting lipid profile, fasting glucose and HbA1c.

Three to five yearly follow up

Every three to five years, consider repeating the following tests: echo three to five yearly; thyroid/coeliac antibodies five yearly; hearing test five yearly; and, bone densitometry scan recommended five yearly.

Pre-pregnancy

Cardiac magnetic resonance imaging and uterine ultrasound scan should be performed prior to considering pregnancy.

Patients will require referral to a specialist fertility unit. In vitro fertilisation, using a donor egg, may be necessary.