Hi Sally, I bled from the beginning of my pregnancy until about 16 weeks, all the colours of the sun and at times very heavy. It was extremely scary and due to blood clots/subchrionic heamatoma (sorry about the spelling.) At my 20 week scan there was still a 5cm one hanging around and I was told it would either absorb or bleed out or just stay there. At the time, I was told it was a risk because the bleeding of the clots may irritate the uterus and therefore cause the uterus to think that it had to "expel" and deliver my baby. Once again scary however - this didn't happen and each time I had a scan there was our little one kicking around. I did ALOT of research about this topic and it seems most people are fortunate with this and the clots absorb. I am having a scan next week to check how mine is going. The Ob has told me that the worst case scenario now is that as my baby continues to grow and runs out of space, the clot may bleed out and cause premature labour. I too was really scared as the measurements for my scan seemed so big! But hang in there and think positive, trust in your little one and best wishes.