The cyclic variation of sodium chloride content in the mucus of the cervix uteri.
19 patients 23-45 years old suffering from primary and secondary infertility participated in this investigation to clarify the cyclic variation, if any, of sodium chloride content in the mucous of the cervix uteri. 17 of these patients exhibited normal ovulatory cycles. The sodium chloride of fresh mucous of the human cervix uteri did not show any cyclic variation and was approximately isotonic (.93) on the basis of 634 analysis, taken in several cases daily throughout the cycle. However, the percentage of sodium chloride in the dry mucous had a cyclic variation exhibiting a very sharp maximum during the ovulation time, reaching a maximum of 40-70% as compared with 2-20% during the other phases of the cycle. The maximum was not observed in infertile women who had no demonstrable signs of ovulation. It was possible to correlate the maximum with a sharp increase in cervical water excretion which was thought to be due to the maximal activity of the luteinizing hormone.