8. Difficulty maintaining an erection.
More often than not; when a man has problems with maintaining erections, it is due to something called atherosclerosis. Atherosclerosis means that there is fatty buildup along the arteries inside the penile shaft. With this lack of blood flow leading to the penis, a man may be often stuck with a un-erect, or half erect penis. So although this is usually due to atherosclerosis, it is also possible that this difficulty can occur due to a prostate tumor that interferes with erections and/or ejaculation.
