Second stage of labor

Question 1

Second stage

Answer 1

1. Pushing stage
2. Begins with full dilation
3. Navigation through maternal pelvis dictated by 3 Ps
   - Power, passenger, passage

Question 2

Passenger

Answer 2

1. Fetal size
2. Fetal attitude
3. Fetal presentation
4. Fetal lie

Question 3

Fetal size

Answer 3

1. Fetal head size (most critical) - indicates cephalopelvic disproportion –> Labor dystocia (difficult/obstructed labor)
2. Macrosomia - birth weight > 90th percentile for gestational age
   - assoc with shoulder dystocia= fetal shoulder is unable to pass below maternal pubic symphysis

Question 4

Fetal attitude

Answer 4

relationship of fetal parts to one another

- Full flexion = chin on chest, rounded back with flexed arms and legs

Question 5

Fetal lie

Answer 5

relationship of fetal cephalocaudal axis ( spinal column) to maternal cephalocaudal axis

Question 6

Fetal presentation
( Cephalic types ) (3)

Answer 6

fetal/presenting part enters pelvic inlet first

Question 7

Breech

Answer 7

Head up; bottom, feet, knees present first

Question 8

Passage

Answer 8

1. Route through bony pelvis

2. Size and type of pelvis

Question 9

Types of pelvis

Answer 9

1. Gynecoid - rounded pelvic inlet, optimal
2. Android - heart shaped pelvic inlet. Reduced midpelvic diameters. Outlet capacity assoc with shoulder dystocia.
3. Anthrapoid - oval shaped pelvic inlet
4. Platypelloid

Question 10

Longitudanal ( ideal)

Answer 10

fetal spine lies along maternal spine

Question 11

Transverse

Answer 11

fetal spine is perpendicular to maternal spine

Question 12

Oblique

Answer 12

fetus is at slight angle

Question 13

Vertex - type of Cephalic presentation

Answer 13

• Vertex -
• Optimal for easy delivery
• Head is completely flexed
• Occiput = part of fetal skull covered by occipital bone is presenting

Question 14

• Brow - cephalic presentation

Answer 14

• Fetal head partially extended

- Sinciput ( part of fetal skull covered by frontal bone is presenting

Question 15

*Face- cephalic presentation

Answer 15

• Face
• fetal head hyperextended
• fetal face from forehead to chil is presenting

Question 16

Frank breech

Answer 16

1. Frank breech - hips flexed, knees exended, bottom presents

Question 17

Complete breech

Answer 17

Complete breech - hips, knees flexed and bottom presents

Question 18

Incomplete breech

Answer 18

both hips not completely flexed and feet present.

Question 19

Shoulder -

Answer 19

transverse lie, shoulders present first

Question 20

Stage 2 of labor consists of

Answer 20

1. Passive phase

2. Active phase

Question 21

Passive second stage

Answer 21

1. lasts from full dilatation until the head reaches the pelvic floor and woman experiences desire to push
2. absence of pushing
3. Rotation and flexion are completed by this point

Question 22

Active second stage

Answer 22

1. Head reaches the pelvic floor and mother experiences desire to push with contractions
2. < 1 hour long otherwise unlikely to occur spontaneously

Question 23

If active stage is > 1 hour long

Answer 23

Consider Ventouse extraction, forceps delivery or C section