I have a friend that has an IUD that absolutely loves it. I know a number of years back, she did have one type of IUD that did cause cramping, but removing it and replacing it with one of the more modern options fixed all of that. I can ask her the details if you like, I just forgot.

I know you're trying to be as natural as possible - but you might want to consider nuvaring. Flexible ring inserted up the vagina that gives a very low dose of birth control hormones - you can leave it in for 3 weeks, remove it, menstruate, and then put another one in - or you can leave it in for 4 weeks, forego menstruating and then put in a new one.

Because of where it's placed, it's a much smaller dose than birth control pills and has less side effects.