Yeah, you never know with RA. I was not in complete remission with my 1st - but I did okay. With my 2nd, I didn't have joint issues, but I had health issues. My immune system practically shut down. I was sick as a dog from 11 weeks until 33 weeks. Bronchitis, Pneumonia, bladder and yeast infections - pregnant and with a 1 year old - it was not fun.
When I had my 2nd, my RA came back and hit me like a semi 10 hours after I had the c-section. With my 1st, I was fine for quite some time.
After you have the baby, you can go back on your meds right away. If your big on nursing, you can try to hold off as long as possible, but if the toss up is nursing and not being able to care for the child vs. bottle feeding and feeling well enough to enjoy the baby - then I'd vote for the bottle feeding.
It's a tough and scary decision. Good luck.