Some children experience slow growth due to factors such as diet, emotional stress, or disease. For a small number of children and adults, their short stature is caused by a medical condition that either slows or stops growth. Norditropin® is used to treat some of these conditions.
What is Prader-Willi syndrome?
Prader-Willi syndrome (PWS) is a rare genetic disorder that affects both boys and girls. About 1 in 10,000 to 30,000 people worldwide are affected by PWS, which can cause childhood obesity as well as difficulties with learning, hormonal and neurological function, and behavior.


What causes Prader-Willi syndrome?
PWS results when certain genes located on an area of chromosome 15 are abnormal or missing. In most cases, children do not inherit PWS from their parents—the error in the genes just happens.
The signs of PWS vary throughout life. Babies with PWS have poor muscle tone and difficulty feeding. As they grow, they often experience an abnormally increased appetite, along with short stature. In later childhood, obesity-related complications may arise, along with scoliosis, epilepsy, and additional behavioral problems.
Children with PWS may have some or all of these characteristics:

In infancy
Poor muscle tone
Lethargy
Difficulty Feeding
Slow growth
Poor reflexes

In early childhood
Facial features such as narrow forehead and almond-shaped eyes
Puffy hands and fingers
Delays in motor and language skills
Learning disabilities
Increased appetite
Obesity
Short stature due to reduced growth hormone secretion
Behavior problems

In late childhood and adolescence
Abnormally increased appetite
Lack of satiety after eating
Food-seeking behavior
Obesity-related complications such as diabetes and sleep apnea

Surprising fact: Many genetic disorders are inherited—passed down from parents to their children. But PWS is different. It occurs when genes from a baby's father do not function properly. These errors in the genes happen randomly, so while PWS is rare, it can occur in any pregnancy.
What about puberty?
Both boys and girls with PWS experience a delay in puberty and lack the pubertal growth spurt typically seen during this phase of development.
How is Prader-Willi syndrome diagnosed?
Before genetic testing was developed, children were diagnosed based on exhibiting the characteristics of PWS such as lethargy and feeding problems in infancy or increased appetite and distinctive facial features in early childhood. Today, if PWS is suspected, the doctor may refer your child to a geneticist for genetic testing to confirm a diagnosis.
In addition, a pediatric endocrinologist may order a stimulation test, or “stim” test, to determine whether your child has growth hormone deficiency (GHD). During this test, a patient is given a medication that causes the pituitary gland to release larger amounts of growth hormone. Over a period of time, several blood samples are taken to measure the amount of growth hormone in the body.

Poor muscle tone and lethargy
Difficulty feeding


Narrow forehead and almond-shaped eyes
Puffy hands and fingers


Abnormally increased appetite
Lack of satiety after eating
Behavior problems related to food

Poor muscle tone and lethargy
Difficulty feeding


Narrow forehead and almond-shaped eyes
Puffy hands and fingers


Abnormally increased appetite
Lack of satiety after eating
Behavior problems related to food
After the diagnosis.
After diagnosing your child with PWS, the doctor may recommend a treatment such as growth hormone and will likely ask for regular follow-up visits to monitor your child’s growth and make sure that treatment is working well.

Find support.
Parents and caregivers of children with growth disorders can find support, community, and education through growth-related patient organizations, such as the MAGIC Foundation.

Norditropin® stories.
Learn more about what life is like for families whose children are being treated with Norditropin®.