The causes of Anejaculation can be psychological and physical. Psychological anejaculation is usually anorgasmic i.e. unaccompanied by orgasm. This again, can be situational or total. Situational anejaculation means that a man can ejaculate in some situations but not in others. For instance, a man may be able to ejaculate and attain orgasm with one partner but not with another. This usually occurs when there is a psychological conflict or a relationship difficulty with one partner. Or he may be able to ejaculate quite normally during masturbation but not during intercourse. It can also occur in stressful situations, as being asked to provide a sample in the lab for infertility treatment. In total anejaculation, the man is never able to ejaculate when awake. Deep-rooted psychological conflicts are usually the cause. Such men, however, usually have normal nocturnal (night) sleep emissions.
Physical (organic) anejaculation, which includes retrograde ejaculation (where fluid goes back into the urinary tract), can occur due to neurogenic and obstructive causes. Diabetes is also noted as a cause.