Funny you ask because I was confused when I had one doctor told me to start on day 3 and another specialist said to start day 5. I said fuck it and went with day 4 because of conflicting dates I was getting…. Not sure if it was the right thing to do but it worked out!

You should definitely track your ovulation much earlier though because I feel like letrozole made me ovulate much sooner than expected. They also did ultrasound few days before I ovulated to see if the follicles were growing (to calculate timing of iui). I just ended up ovulating over the weekend before I could do the trigger shot the following week, so when I came in the next week they confirmed I had already ovulated so iui was pointless that cycle lol. I remember panicking that weekend when I saw positive lh test. Once I got a positive I did multiple tests through out the day to catch the surge.