Need advice on how to get my SO ready for trying for a baby.

So many of our friends are getting pregnant and he comments that they should have been more careful and that they aren't ready to be parents or financially ready. 

I work in childcare and been aching to become a mother for years. When we see babies in public he just looks at me and says no. 

About 3 years ago I was diagnosed with cervical cancer and had a few minor surgeries on my cervix and been told by my gynae that I shouldn't wait much later than 26 to start having kids. I turned 24 this year. I have discussed everything with my SO and he just says that we will get through it together but I feel like I want to move things forward and start trying this year incase we have complications. Unsure how to bring this up again with him or change his mind.