You don't have to stress the female by trying to net her and it's not necessary. I keep large tanks of "Livebearers" and found if I have a lot of floating plants like Anacharis and Pennywort in the tank and feed all my fish a little more and a little more often, the adults show little or no interest in the fry.
Just a thought.
"Fear not, my young apprentice. Just change the tank water."