I developed a hemmeroid after I had my daughter.
Sometimes it bleeds on me.
It could be something more serious and should be brough up immediately with your doctor.
I had the same thing - excessive bleeding from behind. I am used to having loose stools - and with the prenatals that I have been taking my doc told me that it will firm up the stools which can cause rectal bleeding. Also hemmeroids are common in pregnancy. Some apparantly can be seen/felt from the outside and some from the inside. I have heard this too can cause bleeding...not sure if it will cause excessive bleeding or not but it could be a possibility. My doc told me to take Metamicil with OJ and this should help me...so far so good. I would def. bring it up with a doc as it could be an indicator of something more serious, but if you are preg - I would think its just one of those common enough things that ppl just dont openly speak about. Good luck.
Could be anything from hemorrhoids to cancer. You need to see your doctor for a diagnosis.