Gastrointestinal function during the menstrual cycle

Gastrointestinal (GI) complaints (e.g., diarrhea, constipation) are common complaints of women perimenstrually and during pregnancy. The present study looked at the relationship between menstrual cycle phase, daily stool number and consistency over two months, and intragastric pressure changes during fasting and in response to a liquid bolus at two points in the menstrual cycle. The seven subjects, ages 25 to 44, who participated in the study also completed a menstrual history questionnaire. Stool consistency was looser in the early menstrual period as compared to midcycle in all but one subject. Of the six subjects in whom pressure recordings were obtained, four exhibited greater intragastric pressure changes during early menses as compared to midcycle. One subject reported constipation and two subjects reported diarrhea in relation to the menstrual cycle. These preliminary results indicate that menstrual cycle phase may indeed affect bowel function.