Do you try for another baby after IVF & pre-term delivery?

After going through IVF we were able to get pregnant with our son (with our first cycle.) Went into pre-term labor twice, ended up delivering at 30 weeks, staying in the NICU for 49 days. We have 5 great embryos currently frozen. Do we try for another baby? Is it selfish? Do we risk pre-term labor and another stay in the NICU? So many what-ifs.. Any advice? Same experiences? What would you do?