Inclusion Criteria:  Patients with a documented history of infertility, aged 22-40, undergoing fresh embryo transfer after IVF/ICSI, under informed consent. Physiological menstrual cycles (24-35 days), normal endocrine function (FSH ≤ 15 IU / ml), transvaginal ultrasound without pathological findings, free personal medical history, indication for IVF/ICSI.  Exclusion Criteria:  Endocrine or metabolic disorders, e.g., PCO (S), pathology of the uterus and/or endometrium, basal FSH levels> 15 IU / ml, major surgery in the ovaries (removal), and age <22 years and > 40 years old. Active pelvic inflammatory disease IVF/ICSI with donor eggs Previous participation in this trial