Mary,
Here's the most concise, (and seemingly authoritative), article I can find, that describes research about that particular topic, (namely, the effects of estrogen and progesterone on IBS).
http://www.med.unc.edu/wrkunits/2depts/ ... s%20on.pdf
I found that article on this site:
http://www.hystersisters.com/vb2/link.p ... wse&cid=30
I found this, on an Interstitial Cystitis site:
There are many IC patients who avoid severe bladder, muscle and joint pain and IBS symptoms with estrogen replacement. However, there are IC patients who experience bladder pain with estrogen replacement because of the increase of mast cell secretion. What works depends on the individual patient.
That quote comes from the discussion about estrogen, toward the bottom of the page.
http://www.ic-network.com/iclifestyles/march02.html
This abstract describes how discontinuing hormone replacement therapy for five women with colitis, resolved their symptoms. However, supplemental estrogen and/or progesterone was/were apparently the
cause of their colitis, so it's a no-brainer that discontinuing the treatment would eliminate the symptoms.
http://www.ncbi.nlm.nih.gov/entrez/quer ... t=Abstract
Finally, this abstract describes an extensive survey of the literature concerning this topic, but it doesn't provide a definitive conclusion. The full article probably contains some helpful information, but I didn't have any luck trying to locate it on the web. Maybe someone else can find it.
http://www.ncbi.nlm.nih.gov/entrez/quer ... t=Abstract
Tex