ED is used to describe a chronic condition in which a person cannot achieve or maintain an erection at least 50 percent of the time he attempts intercourse. To accurately diagnose the problem and whether the cause is physical or psychological, a healthcare provider will generally ask the man about psychological factors such as stress and sexual desire, and whether or not the man is able to get an erection at times when he is not attempting to have sex.
Men usually have erections while they are sleeping.
It is normal for men to have between two and six erections every night. On the other hand, men who have erections during sleep are generally diagnosed as having ED that stems from psychological causes. The healthcare provider will also review the man's history of vascular, pelvic, rectal, or prostate surgery. Chronic conditions such as heart disease, diabetes, liver or kidney failure are considered, as well as lifestyle factors such as smoking and alcohol consumption. Blood samples may be taken to measure testosterone levels.