For those of you who didn’t feel comfortable telling work you were going through IVF, what did you tell them?

I’ve decided not to tell work I’m doing IVF for various reasons. However, I am tentatively scheduled for FET on October 11 and that is a fairly busy work week as well as some work social events on that day (which I obviously will not be able to attend if all goes as planned). My vacation request would not be approved with how busy the week is so I’m in need of some ideas (I was going to try to say I had a minor operation or surgery such as a mole removal or dental procedure?). Thanks for your help!