Electrolyte interactions in cervical mucus and their relationship to circulating hormone levels

The changes in electrolyte composition of cervical mucus (CM) were monitored during the menstrual cycle, using scanning electronic microscopy (SEM) and energy dispersive X-ray analysis (EDX). Correlations were sought between the electrolytes present in CM, the physical characterisitics of the CM, and circulating levels of gonadal steroids and protein hormones. The results suggest that there is a definite relationship between circulating estrogen levels and electrolyte composition of CM, and also provide information on the secretion of electrolytes during the human menstrual cycle. This information will be of use in development of methods for fertility control directed to the uterine cervix.