Intrafollicular endocrine milieu after addition of hCG to recombinant FSH during controlled ovarian stimulation for in vitro fertilization.

Context: The role of human chorionic gonadotropin (hCG) supplementation on the intrafollicular steroid milieu has been studied. Objective: The objective of the study was to assess the impact on steroid levels in follicular fluids (FFs) after different doses of hCG supplementation to recombinant FSH for controlled ovarian stimulation. Setting: This was a prospective randomized dose-response study conducted at Copenhagen University Hospital, Rigshospitalet, Denmark. Patients: From 62 in vitro fertilization patients, 334 FFs were selected for analyses. Interventions: Patients were treated using a GnRH agonist protocol with recombinant FSH 150 IU/d and randomized from stimulation day 1 to supplementation with hCG: D0, 0 IU/d; D50, 50 IU/d; D100, 100 IU/d; and D150, 150 IU/d. Main Outcome Measure: Intrafollicular hormone concentrations in relation to treatment groups, follicular sizes, and embryo quality were measured. Results: In large follicles, hCG supplementation induced a nearly 3-fold increase of estradi...