Obsessive Compulsive Disorder (OCD) Beyond Blue - OCD is thought to develop from a combination of genetic and environmental factors. A number of factors may increase the risk of developing OCD, including family history, social factors and psychological factors.

Link to the article - https://www.beyondblue.org.au/the-facts/anxiety/types-of-anxiety/ocd

 This video is only an introduction but you can find a  series of 10 videos on understanding OCD treatment by Katie d'Ath, OCD treatment specialist on You Tube