The reason in the past was probably disease and/or unintended pregnancy, and both of those can be fixed now. Also concerns about making sure women wouldn't cheat on their husbands and leave them raising someone else's kid, I think. The third reason, which is still applicable today, is that hiring a sex worker signals "can't get sex without paying, therefore undesirable" but that's probably not too big of a deal.
I'm a virgin at 25 (which is not the same as being a virgin at 55). One reason I haven't used a prostitute is that I don't want to admit to losing my virginity to a prostitute, and I also don't want to lie about it.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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