 Researchers measured various hormones in the saliva throughout the menstrual cycle and found that salivary luteinizing hormone was reliably elevated during the ovulatory period and, for that reason, “salivary LH level is a reliable way to determine ovulation.” A 1983 study of various salivary steroid assays showed that daily salivary progesterone measurements “provides a valuable means of assessing ovarian function”.A 2001 study involved performing daily saliva collection from healthy subjects and plotting these over the entire menstrual cycle.The researchers determined that salivary estradiol and progesterone curves corresponded to the daily profiles normally observed in blood, although of lesser amplitude.