I think it strongly depends on how severe your epilepsy is.
I hadn't had a seizure in 10 years (while on meds), and so I was weaned off my meds. That was 4 years ago. I have been through 2 pregnancies and haven't had a problem, but I do take precautions like not sitting in/near flashing lights and doing my best not to get over-tired etc (my 2 main triggers).
It is definitely something you need to discuss with your doctor though, as seizures during pregnancy can be really bad, so your doctor needs to assess your risk level and decide whether it would be safer to switch you over to a different drug, or to keep you on the same drug, or to wean you off completely.
If you do need to continue taking the epilepsy meds then make sure you take a good high dose of folic acid because that can counter act some of the negative effects the epilepsy meds can have on the foetus (depending on the drugs you take - I was on valproic acid).