Grade 2BC embryo

Has anyone had success transferring a grade 2BC embryo? I just had a chemical pregnancy after transferring a grade 4AB embryo so now I’m worried that transferring a lesser grade definitely won’t be successful (my doctor thinks it was an embryo issue since I got pregnant our first try with my son during a fresh cycle 16 months ago). My husband and I are trying to decide if we should transfer the 2BC embryo or go straight to a fresh cycle to try and get more quality embryos as we don’t want to pay for another failed transfer and then have to ultimately pay for another full round of IVF 🙆🏼‍♀️