I have an iud. I have the copper one, it has made my periods heavier but I have no cramping at all anymore. It hurt really bad when they put it in, none since. It's nice to have birth control over 99% effective, that lasts for 10 years, and isn't hormonal. The only part of it that bothers me is that sometimes I'm really aware of it being in my uterus. Prepare to have to defend your choice if this is what you want. People are seriously misinformed about it. Even nurses and doctors. They will want you to be monogamous, or never want children. I am monagamous, but I do want children. However, there are doctors who are realizing the risk of infertility is very rare, and people can be non-monagomous and still practice safe sex.
My friend had a IUD and shes due in Feb! They had to take it out in emegency surgery Im on the pill, and it makes me happy. I had to try alot then I found one that worked in my body. It didnt lower my sex drive at all, and I havent gained any wieght at all and Ive been on since I was 16.