Description
Premature progesterone (P) rise during GnRH antagonist cycles for IVF is a frequent phenomenon and has been associated with lower pregnancy and implantation rates. Different thresholds of progesterone have been used so far to define its premature rise during the follicular phase of an IVF stimulated cycle. In this study, we evaluated endometrial gene expression on the day of oocyte retrieval according to the level of serum progesterone on the day of hCG administration in GnRH antagonist cycles.Endometrial biopsies from eleven patients were taken with a Pipelle de Cornier (Prodimed, Neuilly-en-Thelle, France) on the day of oocyte retrieval in a GnRH antagonist/rec-FSH stimulated IVF cycle with fresh embryo transfer. Biopsies were analysed for gene expression with Affymetrix Human Genome (HG) U133 Plus 2.0 Arrays and GCOS software (Affymetrix, Santa Clara, CA, USA). Patients were divided into three different groups according to their progesterone serum concentration on the day of hCG administration (A) P <= 0.9 ng/mL, (B) 1 < P < 1.5 ng/mL, and (C) P > 1.5 ng/mL. Serum P was measured with the automated Elecsys immunoanalyser (Roche Diagnostics, Mannheim, Germany). Selected differentially expressed genes were validated with quantitative real-time PCR (QPCR) with TaqMan Gene Expression Assays (Applied Biosystems, Foster City, CA, USA).