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Information relating to specific disease areas aligned to Pfizer’s portfolio and other resources designed for Pfizer medicines.

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Information on how to access Genotropin® (somatropin, rbe) prescribing information and adverse event reporting can be found at the bottom of the page.

Small for Gestational Age


  • Birth length and gestational age are rarely recorded in national databases, resulting in a lack of data on the incidence of small for gestational age (SGA) births
  • Based on study data, it has been estimated that 2.3–10% of all infants are born SGA

Children classified as born small for gestational age may have concurrent diagnoses such as familial short stature, Turner syndrome, or growth hormone deficiency. Approximately 10% of children born small for gestational age do not reach the normal height range. Those whose growth has not caught up by 4 years of age are candidates for treatment with growth hormone.

Defining small for gestational age2

Various thresholds for height and weight at birth are used to define 'small for gestational age', the three most commonly used being:

  • a height at birth that is 2 standard deviations or more below the population average, or

  • a weight at birth that is 2 standard deviations or more below the population average, or
  • a weight at birth below the 10th percentile.

The international consensus definition of 'small for gestational age' is a length or weight at birth that is 2 standard deviations below ( −2 SD) the population average for birth or weight.

In addition to accurate measurements of a newborn's weight, length and head circumference, the diagnosis of small for gestational age requires accurate assessment of gestational age and valid data from a reference population.

Identification of SGA is important because infants are at an increased risk for3​​​​​​​:

  • Perinatal morbidity
  • Associated health problems, such as neurodevelopmental disorders
  • Persistent short stature
  • Metabolic alterations in later life

Clinical presentation of SGA4

  • Similar physical characteristics to those of normal-sized infants:

    • Skin appearance, ear cartilage, sole creases
    • Alertness, spontaneous activity, zest for feeding
  • Features that may present specific to SGA infants:

    • Thin
    • Decreased muscle mass
    • Decreased subcutaneous fat tissue
    • Facial features appear sunken
    • Umbilical cord appears thin and small

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Small for Gestational Age

Find out more about how Genotropin can help your patients that are Small for Gestational Age on our Genotropin brand site

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Genotropin Homecare

Pfizer offers a range of homecare and patient support services to Genotropin patients

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Paediatric Growth Hormone Deficiency

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The Genotropin Delivery Portfolio

Learn more about the 3 devices available for Genotropin patients on our Genotropin brand site

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PP-PFE-GBR-2688. December 2020