Insomnia is difficulty in getting to sleep, staying asleep or getting enough good quality sleep night after night.

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The most common sleep problems in children are difficulty falling asleep and staying asleep and overall insufficient shut-eye.

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Anxiety attacks, depression, sleep disorders, flashbacks, and difficulty trusting people are common symptoms of PTSD and of finding out a spouse is gay.

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CO2 can build up in confined spaces and high levels of CO2 can produce a variety of health effects that can affect sleep, like headaches, dizziness, restlessness, difficulty breathing, increased heart rate and sweating.

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Another study of 119 cancer patients with difficulty sleeping found valerian before bedtime for two months had no significant effect on sleep scores calculated from a questionnaire filled out before the study and after two months.

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According to the National Sleep Foundation's 2004 Sleep in America poll, 13% of school-age children have difficulty falling asleep at bedtime and 26% of preschoolers seem sleepy or overtired during the day at least a few days a week.

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Signs there may be a problem include difficulty or pain when passing urine, the need to pass urine more often, broken sleep due to increased visits to pass urine, waiting for long periods before the urine flows and the feeling that the bladder has not emptied fully.

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