Seminal plasma and serum samples are collected and miRNA and piRNA are analyzed. Steroid hormones are analyzed by liquid chromatography-tandem mass spectrometry. The participants are given a physical examination and testicular ultrasound. The primary aim of this study is to develop a tool to better estimate the sperm recovery rate (SRR) of azoospermic men scheduled for MD-TESE. Since no data have been published presenting miRNA and piRNA levels in men with normal semen, a secondary aim is to describe the levels of miRNA and piRNA in unselected men. Third part of this study aims to find if medical treatment improving semen parameters affects miRNA ja piRNA findings.