QUESTIONS AND ANSWERS
Traditional, *biomedical definition* of 2nd stage labor - ANS begins when the cervix is
completely dilated, ends with birth of
alternative or *physiological definition* of 2nd stage labor is - ANS begins when the woman
experiences involuntary reflexive urge to push (cervical dilation is not relevant), ends with birth
of
Ferguson Reflex - ANS results in a surge of oxytocin that enhances contraction strength &
pushing effectiveness in second stage labor
nearly all ♀ feel the urge to push @ about the same time that their cervix reaches complete
dilation - ANS *false* may occur as soon as 5cm, when presenting part is descending
Know the *physiologic basis* for the *urge to push.* - ANS ‣ Ferguson Reflex: stimulation of
the nerve plexus that generates an urge to push via a surge of oxytocin.
‣ Occurs as the presenting part descends and applies pressure on the pelvic floor.
‣ Usually considered to occur at +1 station
1
Page
@COPYRIGHT @THEBRIGHT 2025/2026
, Is there evidence that pushing prior to complete dilation causes complications? - ANS *No
evidence showing harm*
Anectdotal thought that early pushing -->can cause cervical edema or cervical lacs
What is the impact on *outcomes* of *delaying pushing* when ♀ reach complete dilation
before an urge to push develops? - ANS ‣longer overall 2nd stage
‣ less active pushing
Typically good outcomes with passive descent, fetus descends and internally rotates.
‣ ↑sed chance of spontaneous deliveries,
‣ fewer operative deliveries,
‣ less maternal exhaustion
‣ no ↑ in adverse maternal or newborn outcomes.
- conflicting info
- some studies show more c/s & operative vag deliveries
*coached* pushing *effects* - ANS ‣ ↓'ed fetal O2
‣ ↑'ed perineal trauma/ lacerations
‣ impaired PP pelvic function in those who were directed to push using Valsalva maneuver,
‣ less favorable urodynamic indices
◦ significantly ↓ed bladder capacity,
◦ ↓'ed first urge to void volume,
◦ > pelvic floor descent @ 3 mos PP
‣ longer duration of second-stage labor
‣ less maternal satisfaction w/pushing phase
closed glottis pushing - ANS AKA Valsalva maneuver is linked to
2
Page
‣ childbirth perineal lacerations
@COPYRIGHT @THEBRIGHT 2025/2026