I would say there is an upside and a downside.
I do enjoy feeling more cleaned out! If the monthly cycle is cleansing, I think people like us get a double benefit.
But at the same time it can feel more yucky - like (NOT to be gross) stuff is just coming out everywhere!
Fortunately, I don't really have any problems, just the occasional mild cramping and a few zits. The only soy I ever ate was the occasional tofu, and it makes my body temperature shoot through the roof, I can feel the heat coming out. After reading the article at thedoctorwithin.com I think I will just avoid soya as a general rule. Have you tried rice milk?
And by the way if the retroverted uterus has that effect on periods - how about pregnancy?! Wow I can only imagine 9 months of something special with the colon!