Couples will sometimes fight over who sleeps in more. According to science, it turns out your wife should be the one sleeping in, not you.
"In fact, women need 20 minutes more shut-eye than the average man." writes study authors. "And that's down to a woman's busy, multi-tasking brain." "One of the major functions of sleep is to allow the brain to recover and repair itself," says Professor Jim Horne, the director of the Sleep Research Center at Loughborough University and author of Sleepfaring: A Journey Through The Science of Sleep." During deep sleep, the cortex — the part of the brain responsible for thought memory, language and so on – disengages from the senses and goes into recovery mode."
"The more of your brain you use during the day, the more of it that needs to recover and, consequently, the more sleep you need. Women tend to multi-task — they do lots at once and are flexible — and so they use more of their actual brain than men do. Because of that, their sleep need is greater. A man who has a complex job that involves a lot of decision-making and lateral thinking may also need more sleep than the average male — though probably still not as much as a woman." He continued.
"This is because women's brains are wired differently from men's and are more complex, so their sleep need will be slightly greater. The average is 20 minutes more, but some women may need slightly more or less than this."
So in every sense, yes, women's brains are more complex and need more time to relax and recover overnight.
Another study that examined 210 middle aged men and women found that women suffered greater health issues from lack of sleep than men.
"We found that for women, poor sleep is strongly associated with high levels of psychological distress and greater feelings of hostility, depression, and anger. In contrast, these feelings were not associated with the same degree of sleep disruption in men."