As shown the studies of Boston University, if a man is sleeping more than 9 hours per day, the probability of successful fertilization of the egg is reduced by 42% compared with the standard eight-hour sleep.
This conclusion was made on the analysis of 695 couples who have tried to conceive for six months. It was found that not only excess of sleep is bad, but also chronic lack of sleep (at least six hours per day). In addition to the duration of sleep, the quality of nighttime sleep plays an important role. There is a negative effect, if sleep is often interrupted or a man can not fall asleep immediately. Scientists believe it’s because of the hormonal nature. Some of testosterone in men is produced at night.
Related: Infertility in Men
By the way, last year the experts came up with a surprise recommendation. They have proven that having sex twice an hour increase fertility in men by three times. Scientists from North Middlesex Hospital found: the success in the treatment of infertility by intrauterine insemination (IUI) reached 20%, if the man handed a second semen sample per one hour. Typically, the probability of conception after IUI is approximately 6%.