I don't know about all female pups, but my Annie who is 4 years old still doesn't give me any signals whatsoever. She and I will be "talking" and she will just squat and pee on the carpet.
The one thing I have noticed is that when she gets up off my lap, she will turn around and look at me and that's my queue to take her to the kitchen to her pee pad. So far, we haven't had any accidents....knock wood!