Abstract
The present study was designed to examine the daily fluctuation of saliva secretion in women during the menstrual cycle. Saliva was collected for 5 min every hour from 9:00 to 20:00 by the spitting method. The total volume of saliva secretion, amylase activity, protein contents and pH were measured. Saliva secretion showed diurnal rhythmic changes, but saliva amylase activity and pH did not vary. Saliva volume flow and amylase activity were significantly higher in the ovulatory and luteal phases than during the menses and follicle phases. The level of salivary protein was highest in the follicle phase. Salivary pH was lowest in the luteal phase. These results demonstrate that the volume and composition of saliva change diurnally and during the menstrual cycle.