I just went off last September and had not had a period in ALL of those years. I would actually forget women get periods! It was sooooo nice! I loved Depo and I would not worry about it as the doctor told me that it was okay. I thought about it a couple times during all those years but really did not give it any more thought as the doctor told me it was normal and fine. It is not because of the depo. I also never had any side effects other than not having a period, but I know everyone is different. I absolutely loved it.