Many think of it as 'sticking.' implantation in humans always occurs when the embryo is between 6-7 days old. A very popular concept on the internet now in 2012, 'implantation bleeding, ' is speculative and mostly not useful.
Also, urinary stones can form in the bladder lining due to an accumulation of debris and chemicals. Broken blood vessels can cause blood in the urine, often because of torn or enlarged veins on the inner surface of the prostate. Blood in the urine also can be caused by the sudden stretching of the bladder wall.
As the prostate gland is located beneath the bladder, and the urethra is through prostate, when the prostate is enlarging and oppress the urethra, you may got urinary problems. There still remains dispute on the causes of prostate enlargement. There is one view that BPH can be affected or aroused by sexual intercourses. And there are researches indicates that men who have 2 times per week intercourses in their youth, and have one time per week, and one time every two to three week, have lower BPH morbidity. Also their prostate enlargement is slighter.