Soovivor
(media.scored.co)
So there wasn't even 6 million jews in the areas the Germans eventually controlled even before the war, and many fled prior and during. So far fewer than 6 million were even in those areas the entirety of the war. And why would they breed more babies in a war where they were specifically being targeted for extermination? A baby would just make it more likely that they would be caught, and it would die from just the hardships of war anyway!