That is honestly a very hard question to answer as never encountered it personally.
If I knew going in, it might affect me and confuse my sense of sexuality (again, hard for me to say without experience).
If I did not know, and for example my wife were to reveal such a thing I would still love her, but I may feel hurt to keep something like that from me (not sure how she would).
I do agree a major issue is children in any relationship and how either party feels about it. I would like to have a child someday so that would be an issue. However, if my wife or I were unable for what ever medical reason I would not divorce her. Not sure how I feel about adoption to be honest as another issue never really thought about. I lean no, but that is with expectation of have a child of my own someday still.
Not a full and definitive answer, but this feels morally grey to me in regards to who and why we find people attractive. I made a point to never date smokers for example as habit really bothers me. Can call me prejudice I suppose, but think who we elect to date or marry is ultimately our own selfish decision on what we want.
