Pregnancy and medication

I am 30 years old woman with epilepsy petit-mall(just when I sleep).I get TRILEPTAL twice a day@300 mg(produced by novartis pharm USA).Trileptal contains Oxcarbazepine which closelly related structurally to carbamazepine. I have read the test to rat,rabbit was bad. My neurology doctor said I must get it if not I can get seizure and miscarry.
My obgyn doctor suggest folic acid once enough a day but it is not reduce TRILEPTAL's side effect, he said that Oxcarbazepine's side effect 8 percent.What does it mean and can the fetus save if I continue this medicine?
Thank you.

[Yao Sun, MD, PhD]

It sounds like you already know that Trileptal is Pregnancy Category C.  This means that there are some animal studies showing harm to the animal fetus, but there are not enough human studies to determine how harmful the drug is during human pregnancy.  Drugs like Trileptal can be used during a pregnancy when the physicians (your neurologist and obstetrician) feel that the benefits of the drug outweight the risk.  This needs to be decided on a case by case basis.  It sounds like your physicians have made this recommendation to you.  

If you have further questions, you may ask them what alternative drugs might be considered to treat your seizures.  It may be, however, that Trileptal is the drug that they think is the best choice.