[Rapid determination of plasma progesterone. Its value in ovarian stimulation for in vitro fertilization].

Plasma Progesterone levels show definite variations during the periovulatory period of the superovulated cycle similar to those of the physiological cycle. The question arises whether the pattern of these variations is of significance with regard to the success rate of the IVF cycle. This prospective study was conducted with a rapid and highly sensitive radioimmunoassay of plasma progesterone labelled with Iodine 125. A total of 452 cycles were initiated in 328 patients (280 cycles using a clomiphene citrate-HMG regimen, 272 cycles using an association of LHRH analogues with HMG according to three different protocols). Ovarian response was monitored with sonography and rapid plasma radioimmunoassays of 17 beta-estradiol, progesterone and LH (in non-analogue cycles). Plasma progesterone in particular was assayed 17 hours before, at the time, and 7 hours after the administration of HCG. 10,000 UI IM for triggering ovulation. During the Clomiphene-HMG therapy when LH levels are instable, the plasma progesterone assay is highly discriminant between the beginning of a true LH peak (with concomitant rise of progesterone greater than 1 ng/ml, 15.7% of the cycles) and hectic variations of LH (no concomitant rise of progesterone, 4.3% of the cycles); the progesterone assay was also able to detect the occurrence of ovulation in 3 cycles without sensible variation of plasma LH (1.1% of the cycles). Pre- and post-ovulatory levels of plasma progesterone also demonstrate a prognosis significance with regard to the chances of success of the cycle, with all the different types of ovarian stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)