marsupial - I want to say that nosebleeds during pregnancy is pretty common, but can not for the life of me recall where I found out this bit of info. Everything is more vascular when pregnant, causing more bleeding. Such as bleeding after sex, brushing teeth etc.
I recall when pregnant with DD I woke up went to the bathroom & had a mouth full of blood. It really freaked me out! Normal. Just rinsed with really cold water & it stopped, but had bleeding gums when I brushed my teeth for awhile. It went away.
Hope the nosebleeds stop!