IUD- Opinions and Facts Please!

Ra

Hi ladies! So I am currently 22 weeks pregnant with #3 and got pregnant while on the pill... I took it at the same time everyday and was very careful not to miss but still got pregnant unexpectedly. I am now looking into the IUD which I have been avoiding but since I’m not looking to have a #4 seems to be the safest route unless I can convince my SO to get the snip snip lol Anyways IUDs terrify me so I want all your stories and opinions on pros and cons of the IUDs both the merana and the copper please! I was going to do the copper bc I feel like it’s more natural for a woman to have her cycle still but since then have heard some bad stories which has me second guessing my choice. Please help!