Esophageal contraction pressures are not affected by normal menstrual cycles

Previous studies of lower esophageal sphincter pressures during the menstrual cycle and pregnancy have suggested that the smooth muscle relaxing effect of progesterone depresses sphincter tone. Results, however, have been contradictory and limited to a small number of patients. We studied lower esophageal sphincter and distal peristaltic pressures during the follicular (days 2-8) and luteal (days 20-28) phases of the menstrual cycle. Twenty normal menstruating women (mean age 31 yr) not using oral contraceptives were evaluated. A low compliance pneumohydraulic infusion system was used for all studies. Lower esophageal sphincter pressure was determined by both rapid and station pull-through techniques. Distal peristaltic pressures were recorded 2 and 7 cm above the sphincter in response to 10 wet swallows (5 cc of H2O). Mean amplitude and duration in the distal esophagus were evaluated. Plasma progesterone and estrogen concentrations were obtained and correlated with changes in esophageal pressures. The results were as follows: (a) unlike prior investigations, we found the menstrual cycle had no effect on lower esophageal sphincter pressure and (b) likewise, no change in esophageal contractions in the distal esophagus was found during the cycle. We concluded that changes in female sex hormone concentrations that characterize the menstrual cycle are not associated with changes in parameters of esophageal motor function.