Seroquel is a pregnancy category C drug, which means several things. Category C drugs have only been studied in animal models, and showed evidence of birth defects and other problems, but there is no data on whether these affect humans. This also means that your doctor could keep you on it if he/she thought the benefits outweighed the risks.
Seroquel is apparently recommended in pregnancy if nothing else works, though, so you could maybe find another mood stabilizer to work with in the mean time, since you're not doing so well without meds.
According to a NAMI article (google mood stabilizers pregnancy), lithium and first generation antipsychotics are the best choices for pregnancy. Other articles suggest lamotrigine (lamictal) as a reasonable choice. They advise to AVOID depakote completely.
It's not really understandable if your doctor refuses to treat you at all until you are done your pregnancy, especially if you are symptomatic. You should tell him/her about your symptoms, and ask to discuss your options. You should also talk to your ob/gyn, since they might have more experience with the effects during pregnancy.
Overall, everything has some risk, and you need to weigh those risks against the benefits for any course of action. People who stop their bipolar medications are at a significantly increased risk of relapse and bad effects from their bipolar. Bipolar meds could have a risk for the fetus, although in some meds it seems to be a small risk. The decision is ultimately yours.
I am on fluoxetine. Think is ganartic. Seems to be working pretty good. Takes a while to kick in. And my doctor put me on it once found out I was preg. And I am pregnant with my second child. I so not remember what I was on the first pregnancy. I have seen your screen name on the pregnancy forum..
I understand your pain I was evaluated twice and was told I was bipolar 2 my anxiety us so bad I could never start therapy my general doc put me on some meds but the same day I gound out I was preg I stop taking scare to harn the baby I havent been able to sleep and feel very exausted obgyn tranfer me to a high risk clinic hopefully my new doc can help !! they do say that there are some safe meds dat can be taken for this!! Im trying to get by as I can also just cant wait 2 more weeks to see new doc!! goodluck u r not alone!!