My pregnancies were both unmedicated and went fine - they both occurred before I knew I had BP. Post partum was like all 7 layers of hell combined, and it lasted for YEARS. I was dumb and didn't get any help after my first child; I didn't tell my doctor about the depression at all. I had a miscarriage between my first and second babies, so my hormones were all over the place for many years. With my second (and last) child, I told my doctor ahead of time about the PPD I had after my first. I was put on an anti-depressant for awhile after the 2nd - even though the PPD was unbearable, the anti-depressant might well have been worse for how absolutely apathetic it made me about everything. Nothing mattered at all. I wasn't upset and sobbing all the time, but there was no feeling about anything at all, ever. None of this was helped by the fact that I didn't sleep through the night after my first baby was born for nearly a decade. Even when everyone else slept through, my biology was hard wired to listen for and be alert to every single sound in the house. I'm still that way (my youngest is almost 7 now), but less hypervigilant; I can fall back to sleep more easily with the help of some nutritional supplements that are good for getting to and staying asleep.

So, you have an advantage here. You already have a diagnosis, and you know what meds already work for you. Finding a safe regimen is super important, and it sounds like you're already on that path. And, you will likely have great aftercare with close monitoring of your mood and awareness on the part of both you and your care team of flags for concern. That's all promising!