What Causes Vaginal Bleeding In An Infant?

Hi Doc,i have a 8month old daughter today as i was cleaning her after she passed her motion i saw kind of yellowishwhite something on the diaper which .i thought is white discharge and during this as i was cleaning her vagina i saw little blood stains on the wipes i didnt put any diaper after that so that i can check is there any more such blood but nothing after that can u help