I want to try anal sex but my girlfriend isn’t interested. How can I convince her to give it a go?

If she is not interested then nothing will convince her. Everybody has their own boundaries and it is very important to respect these. It is also important that people are not pressured/coerced into doing things they don’t want to do. This would be sexual assault and is against the law.

If you're having anal sex, use lots of lube and do not force entry as this can cause tearing.