1) I've suffered weird digestive things when I have my period. The way I have heard it explained in my MCAT class is that the same hormone that causes the smooth muscle of the uterus to contract unfortunately works on all of our digestive organs as well, particularly the large intestine. So that's how I've come to grips with the apparent confusion of the digestive processes during my period.
2) Does a person's menstrual cycle regulate her bowels in any way? I have had some problems. The week before I get my period, I have loose bowels and the week afterwards I am quite constipated. Is this normal? Is there anything I can do?