Whether deafness in one ear is hereditary or not depends mainly on whether there is a genetic predisposition in both parents or their families. If there is a genetic predisposition, it may be hereditary; if there are other causes, the probability of heredity is smaller. Hearing loss in one ear can be caused by many reasons. Usually, if the hearing loss in one ear is caused by history of mumps, trauma, viruses, medication, maternal factors, diseases, etc., there will be no genetic predisposition, but if the hearing loss in one ear is caused by both parents or one of the parents due to chromosomal abnormality which results in congenital ear deformity, then there will be a genetic predisposition. If you want to avoid a fetus with monaural hearing loss, you can determine the cause of the disease before pregnancy, check the genes, etc., and insist on obstetric tests after pregnancy to make sure that the fetus is normal.