What is the ruling on concealing the hereditary nature of obsessive-compulsive disorder from a fiancée who desires to have children, after informing her about the existence of the illness without mentioning its hereditary aspect?

It is not obligatory to inform the fiancée that obsessive-compulsive disorder (OCD) is a hereditary disease; it is sufficient to inform her of the affliction itself. It has not been scientifically proven that OCD is a hereditary disease.