Ovarian cysts

This is my 4th cycle. Currently cycle day 3. I used letrazole with trigger shot my previous 3 cycle but my RE thinks I’ve developed a resistance to letrazole so the plan was for me to use clomid this cycle. So I saw my RE today for my first ultrasound of this cycle (cycle day 3) and I have developed large cysts on my ovaries (2 on the right, 1 on the left) with the largest measuring 5 cm. He did bloodwork which he told me looked ok but now he wants to wait 4 weeks to have another ultrasound before proceeding with clomid. Has something like this happened to anyone?