Children with autism symptoms scored worse in almost every aspect of sleep. Reynolds said that only a few areas – sleep apnea and daytime sleepiness – seemed to have about the same level of difficulty as other children.

Autism itself can wreak havoc with sleep hygiene. Children with autism may have problems transitioning from one activity to another, or may become so in a hurry that they can not calm down, she explained.

"Sleep is a big transition," Reynolds said. "You went from playing or reading or whatever you do to fall asleep."

Children with ASD are more likely to have an anxiety disorder or Attention Deficit Hyperactivity Disorder (ADHD), which can also affect sleep, said Reynolds.

In addition, people with autism may have sleep / wake cycle problems, seizures that disrupt sleep, or lower rates of melatonin, a sleep hormone, according to Autism Speaks.

"The impact of a bad sleep on the child and the family is simply huge," Reynolds said. "This can increase difficult behaviors during the day and decrease the ability to pay attention.For children who are already struggling, lack of sleep can make things even more difficult.

"It also has an impact on your physiological health – obesity, insulin resistance and even immune function are influenced by a lack of sleep," she said.

And lack of sleep affects everyone in the household. "It also has an impact on the family, especially those young children who, if they are fit, are also parents," Reynolds said.

Because every child with autism is unique, her sleep problems are unique, "said Donna Murray, vice president of clinical programs and head of Autism Speaks' autism treatment network.

This means that parents and doctors will need to determine the specific causes of each child's sleep problems and treat them individually.

"We can have a number of problems that contribute to sleep problems at the same time," Murray said. "We may have to deal with some simultaneous interventions to fight against sleep."

For example, some children may need to take melatonin supplements under the supervision of their doctor, said Reynolds. They may also need a specific appeasement routine before going to bed.