I am supposed to start Letrozole this cycle, and my doctor was going to call in my perscription Thursday evening after we spoke.  Well she forgot and now I can't get a hold of anyone until Monday.  My question is, I was medium spotting yesterday I wore a tampon, but probably didn't need to until last night around 5:00pm when my flow started to become heavier.. So, what have your doctors told you in regards to counting CD1?!  Is it from the first full day of flow? Or should I count yesterday even though my full flow didn't start until the evening? You help is much appreciated, since I will be super bummed if I am unable to get on letrozole this month because my window was missed😔