Human granulosa cells are follicular cells surrounding the oocyte. Human granulosa cells are retrieved during in vitro fertilization a process where patients undergo hormonal stimulation including FSH and LH/hCG stimulation. Under the influence of the luteinizing hormone (LH) a process called luteinization they differentiate to luteal cells and contribute to the corpus luteum. Therefore, this cellular system is a good model for human corpus luteum (CL). To study processes within the human CL, IVF-derived GCs from patients were cultured for two to five days and then analyzed with mass spectrometry based shotgun proteomics.