Precum!

Hi

Yesterday I had sex with my GF, I were just about to start the sex and I hadnt taken off my panties, just rubbing my penis to her. If I had a precum then,
, could precum pass through my panties and makes her pregnant just by rubbing my penis in panties which are wet of precum ?
I had not ejaculated and hadnt ejaculated for a week before, and she is in her last week of her period.