Use of the Architect-i2000 estradiol immunoassay during in vitro fertilization.

Abstract

In women undergoing in vitro fertilization and embryo transfer (IVF-ET), serial measurements of 17β-estradiol (E2) can be used to monitor follicular growth, and serum E2 has been shown to be correlated with the number and diameter of preovulatory follicles observed on transvaginal ultrasound scan (1)(2)(3)(4)(5)(6). The serum E2 concentration is therefore an essential variable for evaluating the progression of stimulation, adjusting daily gonadotropin therapy, predicting the optimal day for induction of ovulation \[administration of human chorionic gonadotropin (hCG)\] (7), preventing ovarian hyperstimulation syndrome (8)(9), and ensuring that pituitary function is adequately suppressed if a long-acting gonadoliberin-releasing hormone agonist (GnRHa) is used before stimulation (10). Another major use of E2 measurements is to evaluate ovarian function at day 3 of the menstrual cycle to determine the prognosis of IVF-ET (11). Because results must be available within a few hours, rapid and automated assays are required. In this study, we measured E2 with a new automated assay that could be used in random, continuous access mode and assessed its usefulness for monitoring ovulation stimulation for IVF-ET. The Architect-i2000 E2 (Abbott Laboratories) assay is a competitive two-step immunoassay based on chemiluminescent microparticle immunoassay technology and can be performed in 29 min. The ACS-180 E2 assay (Bayer Diagnostics) is a competitive one-step immunoassay based on solid-phase antigen-linked technology and chemiluminescence detection and can be completed in 15 min. The luminescence reaction and the calibration procedure are identical for the two E2 immunoassays. The two methods are linear up to 3670 pmol/L and use monoclonal antibody derived by coupling the E2 molecule at the specificity-enhancing sixth position. The within- and between-run imprecision, detection limits, and functional sensitivities of these assays have been reported …