Symptoms may include:
Affected children have an intense craving for food and will do almost anything to get it. This results in uncontrollable weight gain and morbid obesity. Morbid obesity may lead to lung failure with low blood oxygen levels, right-sided heart failure, and death.
Signs of Prader-Willi syndrome may be seen at birth. Newborns with the condition are often small and very floppy. Male infants may have undescended testicles.
As the child grows older, laboratory tests may show signs related to morbid obesity, such as:
There may also be signs of right side heart failure and knee and hip problems.