What Should the Nurse Know with Regard to Primary and Secondary

What should the nurse know with regard to primary and secondary powers?

A) Primary and secondary powers are responsible for effacement and dilation of the cervix.
B) Effacement generally is well ahead of dilation in women giving birth for the first time;effacement and dilation are more together in subsequent pregnancies.
C) Scarring of the cervix caused by a previous infection or surgery may make the delivery a bit more painful,but it should not slow or inhibit dilation.
D) Pushing in the second stage of labour is more effective if the woman can breathe deeply and control some of her involuntary needs to push,as the nurse directs.