Once you are completely dilated, it is time to start pushing.
Pushing is considered a valsalva maneuver.
Usually you will be asked to push 3-4 times with each contraction holding each push for a count of 10.
Pushing may only be necessary for a few minutes but for some it may be required for 2-3 hours to effect delivery.
Because pushing takes a great amount of energy, it is recommended that mothers exercise regularly during pregnancy so they can be in good shape when the time comes to start pushing.