I wish I were infertile
Are you joking? Why don't you want to have kids?
I don't want to have kids anymore, they are too much burden.
It is okay to not want children or any more children.  You can practice birth control, too.
Nah, I'm going to try to get a uterus loan so that people can be pissed off about it.
It's fine to not want kids, but you shouldn't try upsetting others. Just be fine with your choices and don't think too hard about what anyone thinks about it, if you are happy then that's all that matters.