With the women I worked with personally, I did notice they experienced some swelling until they dropped the grains--often in the second trimester. I didn't track their diets to see how many starchy carbs from vegetables they were eating, so I can't fully answer your question! All of them ate fruit, from what I remember.
If you read the Primal blogs I linked to at the bottom of the article, none of the moms seemed to experience any bloating or swelling.
And yes, blood sugar stabilization seems to be a common theme--but only for those who could stay away from the grains totally.