A lot of people have concerns about their sex life. This means not being able to sustain an adequate erection. Premature ejaculation in the male. Ejaculation comes too early. The concern, though, is not the exact amount of time, but that ejaculation comes with a minimum amount of stimulation sooner than the person wants it to come.
Less blood can flow to the genitals.
Even the arteries and veins in the penis can be involved. The use of any substance that alters the sexual response. For example, some anti-depressants may lead to impotence or failure to achieve orgasm. For example, prostate surgery can result in impotence. A medical evaluation is the first step.