An assessment of the dual-analyte enzyme immunoassay for ovulation timing.

In a search for simpler, more efficient methods of monitoring ovulatory function, either to assist in the investigation of the infertile couple or for contraceptive or fertility control purposes, a number of new methods have been developed. One of these, the OVEIA dual-analyte system is now available for laboratory use. The principle behind the system is the simultaneous measurement of urinary oestrone-glucuronide and pregnanediol-glucuronide. The resultant signal is quantified using an enzymatic photometric endpoint denoted by the relative absorbance (RA%). The application of the OVEIA system to the monitoring of urine samples over the periovulatory period in ovulatory and non-ovulatory cycles from regularly cycling but infertile women is described and the changes in RA% compared with synchronously measured changes in plasma LH and plasma oestradiol concentrations, salivary progesterone profiles and measurements of follicular volume. It is concluded that the OVEIA system is simple and quick to perform and the results obtained compare reasonably well with equivalent direct and indirect indicators of impending ovulation (e.g. increasing plasma oestradiol concentrations or changes in the volume of the follicle). However, as is the case with other endocrine methods, definitive information about the presence or absence of follicular rupture cannot be obtained.