Luteal phase salivary progesterone concentrations in ovulation-induced cycles

Serial paired plasma and salivary progesterone (P) levels were determined in 21 ovulation-induced cycles of 13 women and in 162 luteal saliva samples of 21 normal cycling women. Mean +/- standard error of the mean (SEM) salivary P levels in all ovulation-induced cycles were similar to normal cycles and were 294 +/- 31.5 to 499 +/- 75 pg/ml, whereas the corresponding plasma P levels were 24.9 +/- 5.0 to 51.4 +/- 16.6 ng/ml. Paired plasma and salivary P levels correlated significantly in women induced with clomiphene citrate (r = 0.82), follicle-stimulating hormone (r = 0.80), human menopausal gonadotropins (r = 0.78), and in those who became pregnant (r = 0.95). Luteal phase salivary P levels were 1.0% to 1.3% of the corresponding plasma levels in ovulation-induced cycles. These findings indicate that salivary P may be a useful and convenient alternative to plasma P for assessing ovulation.