Urinary concentrations of steroid glucuronides in women taking oral contraceptives

The aim of this study was to use measurements of urinary steroid glucuronides to confirm the suppression of ovulation of ovulation in women taking oral contraceptives. Urinary concentrations of oestrone-3-glucuronide (E1G) and pregnanediol-3 alpha-glucuronide (Pd-3-G) were measured by radioimmunoassay in early morning urine samples from six normally-menstruating women and six women who were taking combined oral contraceptives. In the normally-menstruating women, E1G concentrations, and the E1G/Pd-3-G ratio, increased 2-3 fold before ovulation. There was no midcycle increase in either measure in women taking oral contraceptives. We suggest that measurement of these steroid metabolites provides a means of assessing the anti-ovulatory effects of oral contraceptives.