The pH of the human uterine cavity in situ

A method is presented for the study of the pH of the human uterine fluids and/or mucosa in situ. The hydrogen-ion concentration of the uterine cavity varies during the normal menstrual cycle. A decrease in the alkalinity of the uterine fluids and/or mucosa is associated with a corresponding secretory endometrium. The occurrence of ovulation appears to be accompanied by a period of relative acidity of the uterine fluids and/or mucosa.