I received the first pfizer covid-19 vaccine shot on 08.06. and the second on 29.06.2021. i take yaz bcp for several years now, but i am planning a pregnancy soon. when should i stop taking yaz and should i wait some time before trying to conceive?

Discontinuation of oral contraceptives frequently leads to a 2-4 month period where the Patient has irregular menstruation. This reflects the body's recalibration of natural hormones. It would be wise to use an alternative, non hormonal method of contraception for at least 2 months as you note how your cycle responds. Once your periods are regular again, try for conception.