I had been wanting to find a good animation showing what the inner workings of birthing looks like and tonight I was pleased to find these videos on youtube.
Both are really good at showing the spiraling motion that babies make as they propell themselves out of the womb after they crown. I especially like the second one that shows the peliv outlet view. My critique of both videos is that they show the lithotomy position (flat on back) which is the worst position to birth in, apart from hanging upside down. The reasons that its the worst position is that it reduces the pelvic outlet up to 30% making it harder for baby to navigate the passage, which can lead to improper presentation or cases of shoulder dystocia, contributing to a longer pushing stage, as well as increased fetal distress, decreased fetal heart tones and an increased likelihood of surgical removal via forceps, vacuum or emergency C-section. It also puts greater pressure on the perineum, making tearing more likely. Source: Giving Birth Naturally
Another problem that I have with the videos is that they don't show how the bones of the pelvis move to accomodate the baby.
But other than that, I'm glad to have found these videos!