Increased tissue permeability and sympathetic nervous system hypofunction may be the common link between dysmenorrhea, chronic pelvic pain, Mittelschmerz, and Crohn's disease.

PURPOSE: To determine if severe periovulatory diarrhea in a woman with Crohn's disease for just one day may be related to increased permeability of the large bowel related to hormonal changes that occur at this time of menstrual cycle.

MATERIALS AND METHODS: Dextroamphetamine sulfate was given to a woman whose Crohn's disease was markedly improved by adalimumab but who still had one day of severe diarrhea at mid-cycle.

RESULTS: She did not have any diarrhea or frequent defecation for the first two periovulatory times before she achieved pregnancy. Previously for two years there had not been one month where she did not have the severe periovulatory diarrhea.

CONCLUSIONS: This case helps support the concept that the classic symptoms of Mittelschmerz in women with endometriosis may be related to periovulatory events which either cause increased permeability of an already compromised tissue, whether it be pelvic or bowel or other tissues, or these periovulatory events impair sympathetic nervous system function, which is already impaired.