On a voluntary basis, infertile patients who do not have legally specified diseases that impede or postpone marriage can marry. However, marriage is unsuitable in cases such as severe mental illnesses, including schizophrenia and bipolar disorder, severe intellectual disabilities such as dementia, and during an active phase of certain communicable diseases. This includes untreated syphilis, gonorrhea, AIDS, Hepatitis A, open tuberculosis, leprosy, and others. These diseases may potentially harm the other party, and in such cases, one should not marry or should postpone marriage.