Yes, at least, sex seems to help men sleep. Many men report that they use orgasm, either through sexual relations or masturbation, to aid in falling asleep. In male rats, there is an active inhibition of sexual behavior following ejaculation. During this period, the male rat emits an ultrasonic vocalization and the rat s EEG shows sleep-like activity. For women, the effect of sexual activity and orgasm is unpredictable.
Many women report that sexual activity is alerting, rather than relaxing.
Scientists have observed that, in female rabbits during their sexually receptive phases, sleep is increased after sexual intercourse with a male rabbit and after mechanical stimulation of the vagina without intercourse. However, women report that after sexual activity leading to orgasm, they feel more alert and sometimes annoyed with male partners who, after sex, seem simply to collapse and begin snoring. These different effects in men and women can lead to some discord in relationships. Appreciation that these differences are due to biological factors, rather than personality and insensitivity, may help heal hurt feelings. I have heard that women have more insomnia than men.