No, but having blood in your stool is generally a sign that you need to see a doctor. The father of a friend of mine kept putting it off because (in his words),

No, but having blood in your stool is generally a sign that you need to see a doctor. The father of a friend of mine kept putting it off because (in his words), "he was embarrassed to talk about the topic to his doctor". He had to have a large amount of his lower colon removed and two rounds of chemo. Luckily he survived.