Labor & Delivery: Questions And Answers
At how many weeks do most births occur? ✔️Ans - Between 37 - 42 weeks
What is the mechanism of the onset of labor? ✔️Ans - Poorly understood
Thought to be increased prostaglandin production and oxytocin release
What are the stages of labor? ✔️Ans - First (latent + active)
Begins - maternal perception of painful regular contractions
Ends - 10 cm cervical dilation
Second
Begins - 10 cm "complete" dilation
Ends - delivery of baby
Third
Begins - delivery of baby
Ends - delivery of placenta
Fourth
First postpartum hour
What is the biggest concern during the fourth stage of labor? ✔️Ans -
Greatest risk of bleeding
What are the 3 Ps of labor and delivery? ✔️Ans - Power
Passageway
Passenger
What powers are involved in labor & delivery? ✔️Ans - Uterine contractions
Voluntary maternal efforts
When do uterine contractions begin? How often and intense should a
contraction occur? ✔️Ans - Late first stage
,Every 2-3 min lasting 50-70 sec
40-60 mmHg intensity
How does voluntary maternal efforts assist with labor & delivery? ✔️Ans -
Hastens descent and shortens the 2nd stage of labor
What makes up the passageway of labor & delivery? ✔️Ans - Bony pelvis &
soft tissue
What are two fetal factors that must match the bony pelvis to create the
passageway? ✔️Ans - Fetal size & position
What type of pelvis is most favorable for labor & delivery? ✔️Ans -
Gynecoid pelvis
(Wide & shallow)
What 3 fetal factors determine the perfect "passenger"? ✔️Ans - Fetal lie,
presentation, & position
What is fetal lie? ✔️Ans - Relationship of long axis of fetus to long axis of
mom
What must the fetal lie be for vaginal delivery? ✔️Ans - Longitudinal
What are other examples of fetal lie that are not conducive to an easy vaginal
delivery? ✔️Ans - Transverse
Oblique
What is fetal presentation? ✔️Ans - Portion of fetus overlying pelvic inlet
"Presenting part"
What is fetal position? ✔️Ans - Relationship of bony presenting part to
maternal pelvis
,What is the best fetal position for delivery? ✔️Ans - Left occiput anterior
(LOA)
What is fetal station? ✔️Ans - How high or low the baby is
What are three types of fetal presentation? ✔️Ans - Cephalic
Breech
Shoulder
What is the preferred fetal presentation for vaginal delivery? ✔️Ans -
Occiput
What are different types of cephalic fetal presentation? What delivery is
indicated for each presentation? ✔️Ans - Vertex = occiput
(Preferred for vaginal delivery)
Face = mentum/chin
(Most may deliver vaginally)
Brow = forehead
(C/S usually indicated)
What is the presenting part for breech presentation? What are the different
variations? ✔️Ans - Presenting part = sacrum
A = complete
B = incomplete "footling"
C = frank
What type of delivery is preferred for breech fetal presentation? ✔️Ans - C-
section
What is the presenting part for shoulder presentation? What type of delivery
is indicated? ✔️Ans - Acromion
, C/S indicated
What is external cephalic version? ✔️Ans - Manual external pressure to
maternal abdomen to change fetal presentation from breech to cephalic
When and why would an external cephalic version be performed? ✔️Ans -
36 - 39 weeks
Performed to avoid a C-section
What are anesthesia considerations for external cephalic version? ✔️Ans -
Neuraxial analgesia/anesthesia increases success
Must be prepared for emergent C/S
(Usually performed in the OR)
What are the cardinal movements of labor? ✔️Ans - Engagement = passage
of biparietal diameter through pelvic inlet
Descent
Flexion of fetal occiput
Internal rotation
Extension = fetal head delivery
External rotation = shoulders pass through mid pelvis
Expulsion = fetal body delivered after anterior shoulder moves under pubic
symphysis
Why is occiput anterior preferred over occiput posterior? ✔️Ans - Occiput
anterior allows for head extension to naturally follow the birth canal
A = anterior
B = posterior
At how many weeks do most births occur? ✔️Ans - Between 37 - 42 weeks
What is the mechanism of the onset of labor? ✔️Ans - Poorly understood
Thought to be increased prostaglandin production and oxytocin release
What are the stages of labor? ✔️Ans - First (latent + active)
Begins - maternal perception of painful regular contractions
Ends - 10 cm cervical dilation
Second
Begins - 10 cm "complete" dilation
Ends - delivery of baby
Third
Begins - delivery of baby
Ends - delivery of placenta
Fourth
First postpartum hour
What is the biggest concern during the fourth stage of labor? ✔️Ans -
Greatest risk of bleeding
What are the 3 Ps of labor and delivery? ✔️Ans - Power
Passageway
Passenger
What powers are involved in labor & delivery? ✔️Ans - Uterine contractions
Voluntary maternal efforts
When do uterine contractions begin? How often and intense should a
contraction occur? ✔️Ans - Late first stage
,Every 2-3 min lasting 50-70 sec
40-60 mmHg intensity
How does voluntary maternal efforts assist with labor & delivery? ✔️Ans -
Hastens descent and shortens the 2nd stage of labor
What makes up the passageway of labor & delivery? ✔️Ans - Bony pelvis &
soft tissue
What are two fetal factors that must match the bony pelvis to create the
passageway? ✔️Ans - Fetal size & position
What type of pelvis is most favorable for labor & delivery? ✔️Ans -
Gynecoid pelvis
(Wide & shallow)
What 3 fetal factors determine the perfect "passenger"? ✔️Ans - Fetal lie,
presentation, & position
What is fetal lie? ✔️Ans - Relationship of long axis of fetus to long axis of
mom
What must the fetal lie be for vaginal delivery? ✔️Ans - Longitudinal
What are other examples of fetal lie that are not conducive to an easy vaginal
delivery? ✔️Ans - Transverse
Oblique
What is fetal presentation? ✔️Ans - Portion of fetus overlying pelvic inlet
"Presenting part"
What is fetal position? ✔️Ans - Relationship of bony presenting part to
maternal pelvis
,What is the best fetal position for delivery? ✔️Ans - Left occiput anterior
(LOA)
What is fetal station? ✔️Ans - How high or low the baby is
What are three types of fetal presentation? ✔️Ans - Cephalic
Breech
Shoulder
What is the preferred fetal presentation for vaginal delivery? ✔️Ans -
Occiput
What are different types of cephalic fetal presentation? What delivery is
indicated for each presentation? ✔️Ans - Vertex = occiput
(Preferred for vaginal delivery)
Face = mentum/chin
(Most may deliver vaginally)
Brow = forehead
(C/S usually indicated)
What is the presenting part for breech presentation? What are the different
variations? ✔️Ans - Presenting part = sacrum
A = complete
B = incomplete "footling"
C = frank
What type of delivery is preferred for breech fetal presentation? ✔️Ans - C-
section
What is the presenting part for shoulder presentation? What type of delivery
is indicated? ✔️Ans - Acromion
, C/S indicated
What is external cephalic version? ✔️Ans - Manual external pressure to
maternal abdomen to change fetal presentation from breech to cephalic
When and why would an external cephalic version be performed? ✔️Ans -
36 - 39 weeks
Performed to avoid a C-section
What are anesthesia considerations for external cephalic version? ✔️Ans -
Neuraxial analgesia/anesthesia increases success
Must be prepared for emergent C/S
(Usually performed in the OR)
What are the cardinal movements of labor? ✔️Ans - Engagement = passage
of biparietal diameter through pelvic inlet
Descent
Flexion of fetal occiput
Internal rotation
Extension = fetal head delivery
External rotation = shoulders pass through mid pelvis
Expulsion = fetal body delivered after anterior shoulder moves under pubic
symphysis
Why is occiput anterior preferred over occiput posterior? ✔️Ans - Occiput
anterior allows for head extension to naturally follow the birth canal
A = anterior
B = posterior
