For men with LPE, the cause is unknown but it is believed to be a genetic predisposition. In one family study, 88% of first degree relatives of men with lifelong PE (of less than 1 minute) also had PE of less than 1 minute. Genetic studies have been scant and conflicting but it is possible that people with certain genetics are more prone to be affected by PE.
Medical conditions can sometimes cause PE. Some factors that have been associated with PE include ED, anxiety, depression, hypersensitivity of the glans penis, prostatitis, chronic pelvic pain syndrome, or thyroid disorders. Men with acquired PE often have other conditions that contribute to the issue (e.g., erectile dysfunction (ED), chronic prostatitis, and high levels of performance anxiety).
Whatever the cause the impact on the quality of life of men and their partners is considerable.