Birth control

So I have a question about birth control, so I had the depo shot for 3 years and the arm thing for a couple months. Then I took pills for 2 months and haven’t been on any birth control for a month. I heard that when you’re on any birth control for a while it is harder to get pregnant. Someone told me it could kill eggs? Is this true? Me and my boyfriend are trying to get pregnant, we have only been trying for over a month but I was just curious as to if me being on the depo for 3 years could make it harder to get pregnant.