If you've never had a kid, your doc may measure your cervix to see how the insertion will go. Otherwise- get the copper only IUD. It is amazing. Your periods and cramps will be worse for a while but it is SO WORTH IT. I tried every single hormonal BC and couldn't handle any of them. (crying, crazy, headaches, cramps, did I say crazy?) I'm also allergic to latex and the polyurethane condoms gave me bacterial infections. If you're in a monogamous relationship- the copper IUD is the way to go. Some ladies try the hormonal one because it does a better job of stopping your periods but your body isn't supposed to have those hormones or it would be making them for you. Good luck!