The second stage of labour. This is the time between the cervix being fully dilated and the birth of the baby. It is also called the pushing stage. Typically, if we watch births on TV, we will see a woman lying on her back in bed with her knees drawn up and a team around her yelling, "Push!" "Keep pushing" "Keep going, keep going, we can see your baby's head" and so on. The reality can be very different, if we choose.
Directed pushing can increase the chance of tearing, is thought to contribute to fetal distress and can lead to exhaustion. This can necessitate the use of forceps or a vacuum. Assuming a woman has not had an epidural, she will be able to feel when to push. With an epidural, these pushing sensations are dulled and so directed pushing will be necessary.
Instinctive or spontaneous pushing is pushing that is directed by the woman herself. She tunes into her body and pushes as and when her body tells her to. I think it is unnecessary to elaborate here on the various bodily functions that we experience daily for which no directed pushing is ever felt necessary. Vomiting is another experience for which any form of coaching is truly not needed. Just as our bodies know how to perform all of these bodily functions, so, too, do we know how to birth.
When we observe instinctive and directed pushing, we notice that women who push instinctively tend to have more pushes per contraction, with each push being shorter. When women are told when and how to push, they tend to have fewer pushes per contraction with each push (and breath-holding) being for longer periods. This is thought to contribute to fetal distress as the baby receives less oxygen through directed pushing as compared with instinctive pushing. It is also thought to contribute to more tearing as greater force is delivered to the perineum.