What is the ruling on refraining from marriage due to specific congenital defects, and what excuse is offered to the parents?

If a person is not eager to marry and is secure from falling into the forbidden (haram), then there is no blame upon him for leaving it. However, if leaving marriage is due to a defect in oneself, then if the defect is one that nullifies the marriage contract, such as ratq (vaginal occlusion) or qarn (a bony protrusion in the vagina), the husband must be informed of it before the contract. If the defect is not one that nullifies the marriage contract, then marriage is permissible, though disclosing it is better. It is advisable to inform the mother or someone trustworthy to avoid family problems and to ascertain the nature of the defect, as it might be an ordinary matter or treatable.