I like 3, 4, and 5. Not coincidentally, these are the ones in which she is not facing square to the camera. Unless you have specific elements to show that it's a pregnant belly (such as a shirt s t r e t c h e d across it, or particular side lighting), it can easily come across as just overweight. I'm afraid that's true of the second shot here. The dress in the first shot might be tight enough to pull off the angle (it certainly works in shots 3 and 4) but she is such a small portion of the frame any tightness to the dress loses its impact.
I do like the processing of 3 and 4, I think it has a dreamy feel which suits the subject. Looking at the mom-to-be I suspect you processed these pretty close to identically - it's interesting how they have a different feel to me, I'm guessing just do to the different flora surrounding her.