With the breeding of ghost shrimp, I believe it to be almost impossible to do so unless they're in a species only tank. I've had various numbers in my guppy/ghost tank.
I've seen dozens of different berried females come and go, without ever getting any new Shrimp. Currently have 11 shrimp, 4 berried, and I think the guppies will eat any that make it to the free floating stage.
Once I get my Walstad Jar going, I'll see what happens in a species only setup.