- Delivered to your hotel in Mexico
Updated on October 28, 2026
Medically reviewed by Dr. Adrián Eduardo Cuenca Bravo. Last reviewed October 28, 2026.
In short: Idiopathic short stature (ISS) is height more than 2 standard deviations below the mean for age and sex with no identifiable cause after a full evaluation: normal growth hormone testing, normal nutrition, no chronic disease, syndrome or skeletal dysplasia. Growth hormone can be considered for children with severe ISS and a low predicted adult height, with an average gain of several centimeters. The decision is made by a pediatric endocrinologist with the family.
Key facts
A careful history (birth size, parental heights, chronic symptoms), measurement and growth velocity, examination for body proportions and syndromic features, a bone age X-ray, and blood tests covering thyroid, celiac disease, kidney and liver function, blood count, IGF-1 and IGFBP-3. Girls have a karyotype to exclude Turner syndrome. Growth hormone stimulation testing is normal in ISS by definition.
A label used when a child is significantly short and every identifiable cause has been excluded. It includes familial short stature (short parents) and constitutional delay of growth and puberty (late bloomers), as well as children with no family pattern. It is a description, not a disease, and most children with ISS are healthy.
Short stature is first divided into normal variants (familial, constitutional delay) and pathological causes (endocrine, chronic disease, syndromes, skeletal dysplasias, nutritional). ISS is what remains after the pathological causes are excluded. The 2008 international consensus set the definitions used today.
Pathologic Causes That Must Be Excluded
• Growth hormone deficiency
• Hypothyroidism
• Chronic systemic illness (renal, gastrointestinal, inflammatory)
• Malnutrition
• Celiac disease
• Genetic conditions such as Turner syndrome
Only when these categories have been reasonably excluded does ISS become the most appropriate classification.
Usually as a child below the 3rd percentile who grows at a low-normal velocity along their own percentile. Constitutional delay shows delayed bone age and late puberty with normal final height expected; familial short stature shows bone age matching chronological age and short parents. Falling across percentiles suggests a cause other than ISS.
Confirm the measurement and velocity, plot mid-parental height, exclude nutritional and chronic disease causes, image bone age, test IGF-1, screen for Turner syndrome in girls, and perform growth hormone stimulation testing when IGF-1 is low or velocity is poor. Only after a normal workup is ISS diagnosed. See how growth hormone deficiency is diagnosed.
4. Initial Laboratory Screening
Typically includes:
• Thyroid function testing
• Screening for systemic disease
• Nutritional markers
• IGF-1 as an indirect marker of GH activity
5. Targeted Testing (When Indicated)
• Growth hormone stimulation testing
• Genetic evaluation in selected cases
• MRI if pituitary pathology is suspected
Only after this process fails to identify a cause is ISS diagnosed with confidence.
The FDA label covers ISS with height below -2.25 SD and a growth rate unlikely to allow a normal adult height, in children with open growth plates. The Pediatric Endocrine Society guideline advises weighing the modest expected gain against years of daily injections, cost and the child’s own views. Treatment is more effective the younger the child.
Controlled trials show an average adult height gain of about 3 to 7 cm after several years, with wide individual variation; some children gain more, some little. Families should expect a measurable but modest change, not a transformation. Response is reviewed after the first year, and treatment is reconsidered if growth velocity has not improved.
Visits every 3 to 6 months measure height velocity, review injection sites and check IGF-1; bone age is repeated yearly. Warning signs are headaches with vision change, hip or knee pain, scoliosis progression and glucose changes. Long-term data for ISS treatment show safety comparable with other indications. See side effects.
When height is only mildly below normal, when growth velocity is normal and the predicted adult height is in the normal range, when growth plates are closed, or when the family cannot commit to daily injections and follow-up. Constitutional delay usually resolves on its own with a normal adult height.
To separate normal variants from treatable disease, to decide with the family whether treatment is justified, to set and adjust the dose, and to stop treatment when it is no longer helping. At HGH Vallarta this is Dr. Adrián Eduardo Cuenca Bravo.
Families consult the pediatric endocrinologist in Nuevo Vallarta or by video, complete labs and bone age locally, and if treatment is indicated receive a Mexican prescription for an authorized brand delivered in cold-chain packaging. Follow-up visits can be remote with local measurements. See pediatric growth hormone therapy.
ISS is a diagnosis of exclusion in a usually healthy child. Treatment is an option for the most severely affected, with modest average gains, and the decision belongs to the family and the endocrinologist together after honest discussion of the numbers.
At HGH Vallarta, pediatric cases are evaluated by Dr. Adrián Eduardo Cuenca Bravo. The pathway is a consultation, growth records and labs, and a prescription only when a recognized indication is confirmed. See pediatric growth hormone therapy.
No. It is a description used when a child is significantly short and no cause is found after a full evaluation. Most children with ISS are healthy.
On average about 3 to 7 cm of extra adult height after several years of daily injections, with wide individual variation.
Yes, in the United States for children below -2.25 SD with open growth plates and poor predicted adult height. Treatment decisions are individualized.
In deficiency, stimulation testing shows the pituitary does not make enough growth hormone. In ISS, testing is normal and no cause is found.
Sources