Trying to get pregnant

Patient: I have been on birth control for 12 years. Prior to birth control periods were horrible. Terrible cramps (puking cramps), very heavy flow, lasting 7-10 days and sporadic never every 28 days. I’ve been off birth control for 6 months. Since going off, periods are pretty normal, not terrible like they used to be. Could the drug still be in my body, which is preventing me from getting pregnant?