What causes nausea right before a your periods?

Joys of womanhood. No greater mysteries than being a woman! many women have changes in their bowels before, during their period. Bloating, gas, cramping, pain, diarrhea and even nausea have all been mentioned by patients. Commonly can be fluid shifts and hormone changes that are associated with a period. A more serious condition can be endometriosis, where uterine tissue is outside the uterus on the bowel.