VOLUMETRIC SELF-SAMPLING OF CERVICOVAGINAL FLUID TO DETERMINE POTENTIAL FERTILITY - A MULTICENTER PRE-EFFECTIVENESS STUDY OF THE ROVUMETER((TM))

The aim of this study was to assess how effectively the Rovumeter(TM), designed for the volumetric self-sampling of cervicovaginal fluid (CV F), can be used to locate the minimum period of potential fertility (P PF) during ovulatory cycles, A multicentre, prospective study was unde rtaken of volunteers (attending natural family planning clinics) over three consecutive, apparently normal, menstrual cycles, All women coll ected daily samples of early morning urine and CVF and recorded the vo lumes (to the nearest 1.0 and 0.1 ml respectively), The concentrations of oestrone glucuronide (EG), luteinizing hormone (LH) and pregnanedi ol glucuronide (PG) were measured in all samples of early morning urin e by immunoassay, A preliminary data set was used to optimize an algor ithm to detect the start and end of potential fertility from the volum es of CVF, The end-points used were the normality of each menstrual cy cle from its length, the length of luteal phase, and concentrations of EG, LH and PG, the start and end days of potential fertility from CVF volumes, and the minimum PPF, which was defined as the day of the LH peak minus 3 to day plus 2 inclusive, Overall, 72 women (median age 30 years, range 24-38) were recruited from three centres (23 from Birmin gham, 24 from Milan, 25 from Santiago) and contributed data from 235 m enstrual cycles (median length 28 days, range 23-44). The urinary LH p eak was identified in 228 cycles (97%; median time, day 15 from day 1 of last menses, with range day 10 to day 35), The use of the Rovumeter (TM) gave start and end signals of potential fertility during 138 cycl es (59%), The median length of the derived PPF was 8 days (range 4-18) , The signals covered the defined, minimum PPF in 113 cycles [i.e. 50% of those with an LH peak; range 28% (Milan) to 62% (Birmingham)]. Ove rall 16/72 women (22%) had successful tests over three consecutive men strual cycles [range 2/24 (8%; Milan) to 8/23 (35%; Birmingham)]. We c onclude that signals from daily changes in the volume of CVF as determ ined by the use of the Rovumeter(TM) consistently locate the minimum p eriod of potential fertility in only a small proportion of women.