Aurora Test for ART Donor Patients (AURORA-Donor)

This is a randomized observational study. The main aim is to determine potential oocyte competence predictive mRNA expression profiles in the cumulus cells isolated form individual oocytes. In 2 patient cohorts: 1)GnRH Antagonist \& hr-FSH with GnRH Agonist trigger, 2) Progesterone \& hr-FSH with GnRH Agonist trigger.

Inclusion Criteria Donor: * Patients are 18 to 35 years old * BMI between 17-30 * Regular menstrual cycles * AFC \> 8 * Patient profile in compliance with SEF (Sociedad Española de Fertilidad) directives for egg donation (medical, psychological and genetic screening, informed consent) * Patients' stimulation: GnRH Antagonist \& hr-FSH with GnRH Agonist trigger or Progesterone \& hr-FSH with GnRH Agonist trigger * Patients agree that the oocytes will be denuded for cumulus testing and provide written informed consent for participation to the study Exclusion Criteria Donor: * BMI \< 17 or \> 30 * Extreme irregular menstrual cycles (\40 days) * AFC \< 8 * \