IVF#4... baseline was today and a question

Hi ladies,
I had my baseline this am for IVF#4 (2nd wiht C.heck). I did estrogen priming with a patch in the luteal phase and once I knew I was not PG, I started taking estinyl in the late-luteal phase. I had my baseline today (cd2) and the estinyl is doing its job as my FSH was only 10.5 (typically runds in the 20's). The nurse told me to continue taking the estinyl until Friday and repeat b/w and u/s. I would start stims on Friday night if the numbers are good.

So, my question: is it typical for C.heck to start stims on CD5? I am doing minimal stim. TIA.