I think you'll find that they all talk about vaginal birth in some way. You can do it knowing that the asanas are predominantly devised with the pregnant body in mind, rather than the birth itself. The one I have is like that, even though it mentions birth. In my case I have to adapt certain asanas anyway, because of my SPD and the fact that due to this I will never birth squatting on dry land, simply because my pelvis would give way and I'd crash to the floor doing the splits!
As with all yoga, you go with your body and your circumstances and no more. It's about wellbeing, not depressing yourself over what you can't do - as with any exercise, and particularly with yoga, which has no set level of attainment.
You're only limited by your own mind