54 Obstetrics and Gynecology Board Review •••
❍ Is there a time difference in the latent phase for nulliparous versus multiparous patients?
In the nulliparous patient, the average latent phase is 6.4 hours. In the multiparous patient, the average is 4.8 hours.
❍ What is the definition of the active phase of labor?
The active phase of labor is defined as when the expected phase of maximal slope has been accomplished. The
majority of patients (90%) are in this phase when they are approximately 5 cm dilated.
❍ What is the average cervical change during the active phase for a nulliparous patient?
The expected cervical dilatation in the nulliparous patient is ≥1.2 cm/h.
❍ What is the average cervical change for a multiparous patient?
The expected cervical change in a multiparous patient in the active phase of labor is 1.5 cm/hour.
❍ What is the average length of time pushing for a multiparous patient?
The multiparous patient usually pushes for no >1 hour. However, this may be extended to 2 hours if there is
regional anesthesia.
❍ What is the average length of time pushing for a nulliparous patient?
The average time may last up to 2 hours in the nulliparous patient or extended to 3 hours if the patient has had
regional anesthesia.
❍ What is the definition of precipitous labor?
Traditionally, this is defined as labor resulting in delivery in <3 hours. In a nulliparous patient, labor is also
considered precipitous if the cervical dilatation is >5 cm/h.
❍ What is “failure to progress”?
“Failure to progress” is defined as labor not resulting in cervical dilatation or descent of the fetus.
❍ What is cephalopelvic disproportion?
Cephalopelvic disproportion is the difference in the dimensions of the fetal head and the maternal pelvis resulting
in obstruction of labor.
❍ What is protracted labor?
Protracted labor can be the result of protracted dilatation or protracted descent. Protracted dilatation is progress
<1.2 cm/h in a nulliparous patient and <1.5 cm/h in a multiparous patient. Protracted descent is defined as
descent <1 cm/h in a nulliparous patient or <2 cm in the multiparous patient.
❍ What is the Bishop score?
The Bishop score is a description of the cervix to help evaluate “ripeness.”
❍ How is the Bishop score defined?
There are five parts to the Bishop score including dilatation, effacement, station, consistency, and the position
of the cervix in the pelvis.