Despite major achievements in elucidating many details of the physiologic processes of human reproduction during the past 2 decades, a simple, reliable, and inexpensive method for the prediction and detection of the time of ovulation is still not available. For clinical purposes, studies of BBT and biophysical and biochemical constituents of cervical mucus appear to be the most practical methods of ovulation detection. The development of rapid and easy-to-use urinary LH assays and steroid assay kits for measurement of urinary and salivary estrogen and progesterone or their metabolites may further improve the precision of ovulation timing.