Health risks aside I think each case could be a different way to see it, not just one answer for all. If it's a guy who has a ton of partners and seems like a player/unfaithful kind of person, I wouldn't want to set myself up for hurt and just be another number.
If he genuinely cares for me that's different. I'm one who thinks sex should be a special thing with someone you care seriously for, not just casual.
I'm sure it depends on your partner. For most people in today's world have sex before marriage but when engaged or serious it would probably be best to stay faithful. If one is marrying a religious person that can be a factor too. Particularly if they believe fornicators will burn in everlasting hell.
There is way too much importance placed on numbers!
5 or 50, no matter.
7" or 10", no matter.
38c or 44d, no matter...
