I stopped using Prempro because of blood clots in my legs. I went to the Climara estrogen patch & the progesterone pill. I was on that for about 8 years & didn't develop IBS-DC until about 7 months ago when my uterus prolapsed. Since the uterus was large (like at 4 months pregnancy) it maybe was pressing on my bowels, etc. I had a hysterectomy about 6 weeks ago & I still have the IBS. I'm just on the estrogen patch now since it was a total hysterectomy. I wasn't aware of the connection of HRT with IBS. Good luck with it all.