Does sex improve sleep?
Overall sex is relaxing for couples and releases endorphins which can help you feel better about yourself and slip into sleep. However the impact of sex on sleep differs between the sexes.
Men often fall asleep after sex. Contrary to popular belief that men roll over and go to sleep to avoid intimate cuddle or talk time after sex, the real reason is that their brains essentially “shut down” after orgasm. Researchers monitored brain activity in men before and after sex and found a number of changes. After orgasm men’s pre-frontal cortex’, which is responsible for mental alertness, consciousness, and overall brain activity, decreases in activation. In addition, the male brain is flooded with serotonin and oxytocin after sex, two hormones that are naturally sedative. After sex the male enters a refractory period where it is physiologically impossible to have additional organisms and is uninterested in sex. Essentially orgasm triggers male sexual satiation and for his brain to relax and go to sleep.
Women are different. Women do not go into a refractory state and can be aroused after sex. If the woman is not properly satiated during sex she can feel activated and may have to get up and take a bath, read, or do something else until she feels tired. The key for sex to be useful as a sleep aid is to ensure that both partners are “properly satisfied” as a result of lovemaking.