Recurrent miscarriage is typically defined as the loss of three or more pregnancies in a row. Many factors apart from maternal health have a significant role in miscarriage risk.  According to researchers from Imperial College man’s sperm may sometimes be a factor. Total sperm motility, progressive sperm motility, and normal morphology were all reduced in the Recurrent Pregnancy Loss (RPL) group vs controls.  The DNA fragmentation was 2-fold higher in PRL than in controls group. The researcher published in, the journal of Clinical Chemistry, say this could be because of high levels of Reactive Oxygen Species (ROS).