Interesting question..

But its hard to mistake the female condom and it takes a little time to put in.  I can't see anyone doing that ahead of  time as it might discourage other activities such as DATY?

I would hope that they are not being irresponsible!!!!!!

I had seen a non-pro who I think was posting one night about every 4th month to cover expenses even though she worked two jobs. I started seeing her a couple times a month and she started turning it more into a date, charging me the hourly rate for the whole night and then eventually offering and my accepting BBFS.  Unique situation, but still reason I went with answer 2.

Either way, I did get nervous and a couple months after we stopped the bi-monthlys, I went and did a full blood work-up. I now think, I was just lucky and even in that environment, I wouldn't do again.