Characteristics of salivary profiles of oestradiol and progesterone in premenopausal women.

The objective of the study was to characterize salivary sex steroid levels in 56 women undergoing annual mammography who were participating in a breast density study at the Lynn Sage Breast Center of Northwestern Memorial Hospital, and to determine the predictability of the patterns within women. Saliva was collected daily by the women at home for one complete menstrual cycle and then again at approximately 6-month intervals. The occurrence of sporadic anovulatory cycles was identified in 12 subjects, and persistent oestradiol (OE2) elevation in all three cycles without significant progesterone levels occurred in another five subjects. In addition, both OE2 and progesterone were significantly lower in initial menstrual cycles than in subsequent cycles, suggestive of an effect of participation in the study on hormone levels. Initial salivary OE2 levels were not good predictors of corresponding levels in either follicular or luteal phases of the menstrual cycles at the 6-month intervals. However, after the initial cycle, progesterone levels were highly predictable within individuals over a period of 6 months (r=0.78, P<0.001). The study emphasizes the natural variation among and within women in the absence of any intervention, and indicates the need for properly controlled studies before attributing changes in hormonal levels to therapy. In addition, it emphasizes the importance of sampling at multiple time points when examining the relationship between hormones and risk.