Well, this is really a very interesting situation! And a horribly frustrating one for Lois, I'm sure. She is pregnant, and she has no idea at all how it may have happened, and she is sure she has not had sex with
anyone during the time when her pregnancy just mysteriously started.
The concept reminds me of
To Wake From Dreams by Nicole Sullivan. In that story, a post-TOGOM fic where Clark has not yet revealed himself and his continued existence to Lois, she suddenly and inexplicably finds herself pregnant. As for how her pregnancy happened and who the father turned out to be, why don't you read the story for yourselves?
I'm really interested in seeing how you are going to explain Lois's pregnancy in your story, Daisymay. Who is the father? Is it Clark after all? And whether he is the father or not, what this will do to Lois and Clark? So give us more soon, please!
Ann