Night terrors are an emotional disorder occurring in the first 1/3 of the night (relatively shortly after falling asleep), usually lasting between 1 and 10 minutes.
Nightmares are 'bad, frightening dreams' occurring during the REM phase of sleep, usually in the second half of the night. Occasional nightmares are a normal occurrence. In some children, however,...
Insomnia, frequent awakening, difficulty sleeping, waking too early, restless sleep occurring in menopausal women.
Excessive sleepiness or sleep problems occurring during pregnancy, significantly impeding the proper functioning of the body.