I've been wondering about this too...Sorry this is so long! It's such a sensitive and tricky subject, and different for everyone too. Mainly I suppose it would depend on how serious your condition is, whether you get suicidal, harm yourself or self-medicate with alcohol or whatever. I don't yet have children so feel free to completely disregard me( I would...!)but have been giving this a lot of thought. Are there any organisations that could give you expert knowledgeable advice about this? I know Stephen Fry's programme about manic depression made it look pretty bleak for mothers as for many people the hormones & emotions can be so intense, on top of the usual ones, but there are so many degrees of the illness...
I'm bipolar, and have been on mood stabilisers for a few years, and they work pretty bloody well...am so much nicer & calmer than before! I was completely off the rails, but now unimaginably more calm and rational. But obviously will need to come off them (very slowly to decrease the chances of getting ill again)before ttc, which throws up many questions!
Apart from the worry that I might descend into depression without the drugs, I think in many ways being bipolar as a mother would not be the worst thing in the world. It's made me kinder and less judgemental about people, and I don't think it would make me an unfit parent at all..how many "sane" parents are out there who are just horrible people after all?! (you know, the ones swearing at/ignoring their kids in public, that make your heart ache for them).It shouldn't reflect badly on you as a person, it's largely about chemicals in your brain.
It depends on how well you are able to manage your illness, find ways to cope, recognising triggers and being able to tell when you should be kind to yourself and take it easy, and when to try and "override" the illness and get a hold of yourself, if possible. That said, perhaps this is hugely irresponsible to say as it really does depend on how serious your condition is, and also very much on your partner.
My mother, who is pretty sane and grounded told me that before she had me she was slightly nuts but having to put someone else's needs first really sorted her out. She wasn't bipolar though. I am and so is my dad, and while we have a fantastic relationship he was never really able to cope with family life, despite a few attempts! He's been more of a friend and mentor while the sane stepdads did the actual parenting, lol.