How do you manage hemophilia A carriers with no history of bleeding complications but with mildly low factor VIII activity (6-40%)?  

This is a wide range, if no history of bleeding then do not need factor on a regular basis. But for invasive procedures/surgery/trauma depending on what their levels are at baseline and the bleeding risk of the procedure, you will need to use factor 8, antifibrinolytic agents, or DDAVP. Same about t...