The Glucose-Phosphate Isomerase content of Human Cervical Mucus of Women using either Steroid Contraceptives, an Intrauterine Device, or no Contraception

Abstract

The enzymatic activity of glucose-phosphate isomerase was measured in cervical mucus from women using a diaphragm no contraception (controls) an IUD or some steroid method and from postcoital women. Determination of activity was performed through colorimetric measurement of fructose 6-phosphate formed from glucose 6-phosphate using the enzyme. The cycle was divided into the proliferative phase (days 1-11) the ovulatory phase (days 12-16) and the secretory phase (days 17-32). Among the diaphragm users and non-contraceptors whose enzyme activity was the least of the first three groups activity was significantly greater (p is less than 0.01) during the secretory phase than during either of the other phases. First phase activity in the IUD women was significantly greater (p is less than 0.01) than either second or third phase activity. No significant differences were found among the phases in the steroid women but this groups activity was consistently higher than the activity of the diaphragm or non-contraceptive or IUD group. Postcoital samples had less activity than random samples obtained on days 14 15 and 16 from non-contraceptors. Since semen contains a large activity the results shed doubt on the view that semen enters cervical secretion; or the results might reflect the greater amount of mucus in the postcoital samples. Enzymatic activity increased following secretion or administration of progesterone in the control and steroid groups but not in the IUD group. Since the enzyme takes part in the glycolytic pathway by catalyzing the reversible conversion of glucose 6-phosphate to fructose 6-phosphate the absence of fructose in human cervical mucus is puzzling. The suggested absence of glucose 6-phosphate was confirmed when fructose was formed after small quantities of glucose 6-phosphate were added to cervical secretion.