Pre workout and TTC

My husband and I go to the gym 6-7 days a week. Mostly focusing on bodybuilding but cardio too. We always take pre workout and normally a pump along with that. Does anyone know anything about taking supplements and TTC? I've talked to the Dr but they just tell me to watch out for the amount of caffeine I take and that there really isn't enough studies on it. I of course would stop all supplements as soon as I know I'm pregnant. Any insight would help. Thanks