I did spot with one pregnancy due to a subchorionic hemorrhage. They are not usually harmful unless they are large. It's where blood pools between the uterus and placenta (MOST of them are NOT large).
I ended up miscarrying but it was not due to that (I have an autoimmune condition and have had 7 first/second trimester losses).
It was a relief for me to at least know why I was bleeding. I had actually stopped bleeding several weeks before mybabydied and the hemorrhage was gone on the last u/s I had.
I never would have known I had it ifI wouldn't have requested my u/s report (read it for myself and researched it online). Apparently it warrants so little concern that drs don't usually even mention it. It's a common finding that usually doesn't present complications other than spotting (I was upset though since had my dr just told me I wouldn't have been so concerned about the bleeding :rolleyes: !!).