How many people have gotten pregnant with the iud?

Hey everybody :)

I have a really intense fear of becoming pregnant, so much so I ended up getting on birth control before I even became sexually active w my partner. I got the iud because it seemed to be the most effective, but I see a lot of posts on this thread concerning pregnancy even with it. How often does that happen? Should I make my partner wear protection? I got on bc so I wouldn’t have to but all these posts are making me really nervous. Is pulling out sufficient? 😰