Gums more sensitive in pregnancy?

Hi ladies, bit of a weird one... I have always flossed fairly regularly (once or twice a week) and the last few weeks my gums seem to bleed REALLY easily. There is no pain, swelling or redness anywhere in my mouth and I had a dental check up last month, so I don't think I have any problems. Could it be pregnancy making this happen? I have heard of pregnant women getting nose bleeds, but what about gums? Has anyone else noticed this? I am nearly 20w x