Stages of labor(2)
First stage: it starts from the onset of true labor pain and ends with full dilation of the cervix. 8-12 hr
The first stage is further divided into two phases, the latent phase and the active phase.
In the latent phase, cervical dilation is under 3 cm, the contractions may be infrequent, are usually not more than moderately strong and the patient can tolerate, in active phase, more rapid cervical dilation occurs,usually beginning at approximately 3cm .