When I started Trileptal it caused breakthrough bleeding. It was like having a period every two weeks. The birth control pills my GP put me on did nothing. I was almost willing to go off of the Trileptal even though it was helpful. I just couldn't take not knowing when and if I would have random bleeding. I went to an OB/GYN and she put me on the NuvaRing and that stopped it. My periods are extremely light, pretty much non existent at this point.