Birth Control

Hello! I just stopped using the patch and have not been able to find anything online on around how long it will take to leave my system. I do know most birth controls are effective for the month ahead of time. Any input or suggestions on how long it will take? I have used 3 types of birth control for 10 consecutive years. Studies show that it is totally safe and doesn’t effect conception later. What is everyone’s experience on stoping use of birth control?