i was 24 weeks when i was sitting on the couch watching t.v. when all of a sudden i had a huge flow of blood spilling out.... i started freaking out and sobbing when i ran to my mother and she took me to the hospital. i then found out that my baby was fine, but the nurse asked me, "did you have sex within the past 24 hours." i told then yes and thats when the situation was answered. sometimes during pregnancy and you have sex, your pelvic can get damage and you can start to bleed. its not a huge issue but it is good to go to the hospital just to make sure... if its the same thing as what i just explained then you will more than likely be put on pelvic rest which means nothing absolutely nothing "up there" until your doctor says otheriwse.