I had it with one of my pregnancies. It really ended up being no big deal. It means your placenta is covering your cervix. More often than not it will come up on its own but if it doesn't by the tome you're due then it does mean a c section. You will have ultrasounds every few weeks to keep an eye on it until it comes up. I didn't think mine was ever going to come up and I was terrified I was going to have a c section but then finally at 32 weeks it was where it was supposed to be. There is also an increased riisk of bleeding with a placenta previa but that's not very common.