MONOCLONAL ENZYME-IMMUNOASSAY MEASUREMENT OF ESTRADIOL AND PROGESTERONE RECEPTORS IN INVITRO FERTILIZATION AND SPONTANEOUS CYCLES

So far, the few studies performed on endometrial steroid receptors in in vitro fertilization (IVF) cycles have been carried out by the dextran-coated charcoal (DCC) method. Despite widespread efforts to standardize the DCC assay method, assay results still vary and thus, data obtained in IVF cycles are controversial. In the present article, late luteal estradiol (E2) and progesterone (P) receptor (R) levels were measured by a new monoclonal enzyme immunoassay (EIA) method in endometrial samples obtained from 21 patients in an IVF program who received no embryo transfer (ET) after ovarian stimulation with follicle-stimulating hormone/human menopausal gonadotrophin/ human chorionic gonadotrophin under pituitary suppression with buserelin. Plasma levels of E2, P and prolactin (PRL) were measured in three blood samples collected in the midluteal phase. Results were compared with those obtained in a control group of 21 spontaneous cycles. E2, P and PRL were significantly higher in stimulated than in spontaneous cycles. The level of E2R was decreased in endometrium in IVF stimulated cycles, but PR remained unchanged.