OK, anyone posting with me for more than a week knows that I am a hard mule on the issue of interview attire. IMO, there is almost no excuse not to wear a suit to an interview, and no excuse to wear scrubs to an interview, ever. The latter is just really gross, frankly.
However, that said, even I would cut a 40 week pregnant woman some slack on interview attire. Not enough slack for scrubs (really, that is just never acceptable. If I'm interviewing you, you've lost the job the minute you walk in in scrubs), but enough to let you slide by without a suit, lol. Anything you might wear to church or something should be fine. A dress, or slacks and blouse.
Good luck, on both counts.