There is tremendous mental and emotional effects on both the girl and guy once that happened, which is why there is just so much pain and confusion upon breaking up (just imagine it, it is already very severe even without their physical intimacy; how much more will it be when it is physical as well?)...... sex is meant for marriage man, just as fire is meant for the stove only and not for the whole house.
There is just as much confusion and doubt even there is no breaking up. Marriage fails today because we are playing game.
Don't be fooled by the media, especially the Hollywood (what they know about family and loyalty?).... you won't want to end up hurting yourself as well the one you love.
Everyone of us has the urge and passion... the liquid is always there... the difference lies on who can control it (I mean the timing and location, not that you can keep it always... understood). Keep it till your wedding night. God bless.