A new microscopic technique for study of cervical mucus is presented. This technique consists of stretching the cervical mucus prior to slow drying (under cover slip) in order to demonstrate its biophysical characteristics. Cervical mucus obtained from the proliferative, midcycle, and secretory phases of the menstrual cycle was examined by this technique. In addition, this technique was also used to examine the cervical mucus obtained from one infertile patient who had an abnormal postcoital test. The correlation of the observed dendritic crystal patterns to previously described biophysical properties of cervical mucus is demonstrated. Marked differences were noted in the dendritic crystal patterns in each of the categories.