In my mind, to begin with, each pregnancy happens in a different universe, and V either plans the pregnancy or doesn't mind it happening when he sleeps with the future mother.

I can already see much comedy with Sangwaan.

"I know you're male."
"How would you know that?"
"I see the future. You'll knock me up."
"Ha! This is ludicrous! When is that nonsense supposed to happen anyway?"
"Right now, actually. *jumps V*"