facts, & risks of my placenta being in the front?

lauren
i am 21 weeks today!!! when i went to my dr appointment last week for my ultrasound they informed me that my baby boy was being shy & hiding behind my placenta, and that's also why i'm not showing, but they also reassured me that as my sweet baby grows he could move in front of my placenta. i was hoping to get as much information from other moms who had experienced the same thing & how it effected you, your pregnancy (& if your baby ever moved in front of the placenta), your labor, and your baby. ❤ 
   - i don't know how true that this is, but i HEARD from a friend that it could possibly put you at higher risk for a c section, was this true for you, or did you deliver vaginally.