Normal mechanisms of labour

Question 1

What is the 1st step?

Answer 1

Engagement of fetal head

Question 2

What is the 2nd step?

Answer 2

Descent (fetus descends into pelvis due to gravity + downward pressure of contractions)

Question 3

What is the 3rd step?

Answer 3

Flexion (during descent, baby’s head meets chest due to resistance of soft tissue of pelvis)

Question 4

What is the 4th step?

Answer 4

Internal rotation (when occiput reaches pelvic floor, it rotates to accommodate changes in diameters of pelvis )

Question 5

What is the 5th step?

Answer 5

Crowning (extension of head)

Question 6

What is the 6th step?

Answer 6

Restitution (external rotation, head realigns with shoulders, once head is born)

Question 7

What is the 7th step?

Answer 7

Internal rotation of shoulders

Question 8

What is the 8th step?

Answer 8

Lateral flexion (delivering of anterior shoulders and body)

Question 9

What is the 9th step?

Answer 9

Expulsion (anterior shoulder moves out from under symphysis pubis. Perineum becomes distended by posterior shoulder which is then also born)

Question 10

Nneumonic for mechanism of labour?

Answer 10

Do Frogs In Canada Ride In Limos Everyday?