1. Department of Andrology, University Hospital Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
2. MVZ Fertility Center Hamburg GmbH, Amedes Group, Speersort 4, 20095 Hamburg, Germany
3. Institute of Neuroanatomy, University Hospital Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
4. Centre of Reproductive Medicine and Andrology, University Hospital of Münster, Albert-Schweitzer Campus 1, 48149 Münster, Germany