question about cul de sac

If the woman is laying down, is the cervix up and the cul de sac below and beyond. If so then wouldn’t an up curved penis more than likely strike the cervix? Wouldn’t a slight down curved penis have a better chance of by passing the cervix and go into the cul de sac?

check the attached illustration. I think that in missionary that an upcurve is more likely to hit the crevix, like you say so what I do is when i feel the cervix at the tip of my dick I angle down slightly for a second and slide under it, once I get to the cds the first time I seem to follow the same track wtihout much effort.

That’s a great diagram thank luvdadus