Compared to men, women have shorter sleep time of six minutes. Women tend to wake up 30 minutes earlier than men. woman asleep faster and sleep more soundly than men. but this would make women more prone to insomnia and seasonal depression. Jean Duffy of Harvard Medical School, United States, told Livescience states and time differences in sleep patterns are influenced by the hormone estrogen. Hormone levels change sikardian rhythm (cycle life) people for 24 hours a day. Research conducted on 52 women and 105 men for 2-6 weeks in, a laboratory with dim light, no light from outside. Long days in the laboratory was changed to 20 hours or 28 hours. Not 24 hours like a normal life. By studying the two main indicators sikardian rhythms in sleep-wake cycle and one that is body temperature and hormone melatonin. Research shows sikardian influenced rhythms of natural light. Without influence from outside, the body's natural sikus be shorter or longer than 24 hours. results of the study, 35 percent of women have a shorter rhythm sikardian than men (14 percent). People with seasonal depression can be treated to re-arrange the rhythm sikardian. If less than 24 hours, they need a light that can be adjusted to the brightness at night. In people with a rhythm more than 24 hours need bright light in the morning