Diameter of the internal cervical os increases as labor progresses
0 cm (closed/fingertip) to 10 cm (complete/fully dilated)
Measure with index and middle fingers of examining hand
Use sterile gloves, sterile lubrication, and sterile speculum
Measure with index and middle fingers of examining hand
Use sterile gloves, sterile lubrication, and sterile speculum
Assessment of the cervical thinning
Percentage of normal 3-4 cm long cervix
4cm cervix = 0%
0cm (thin) cervix = 100%
Fully effaced cervix feels paper-thin
4cm cervix = 0%
0cm (thin) cervix = 100%
Fully effaced cervix feels paper-thin
Fully effaced cervix feels paper-thin
Distance of the presenting body relative to the maternal ischial spines
-3 = beginning of second stage of labor
0 = in line with the plane of the maternal ischial spines
+3 = impending<unk> 
+4 to +5 = crowning
False labor is defined as uterine contractions that do not produce cervical changes.
Braxton-Hicks contractions: Brief contractions, irregular in both duration and intensity
True labor is characterized by regular contractions that lead to cervical changes, gradually increasing in intensity and duration
Braxton-Hicks contractions: Brief contractions, irregular in both duration and intensity
Emergent delivery
IVF maintenance
Umbilical cord prolapse
Resuscitative hysterotomy
Breech delivery
Neonatal resuscitation
Shoulder dystocia
Delayed sequence intubation