Week 6 Flashcards
What are the 7 distinct cardinal movements of labour?
ON EXAM
- Engagement
- Descent
- Flexion
- Internal rotation
- Extension
- External rotation/restitution
- Expulsion
Explain ENGAGEMENT - one of the cardinal movements of labour?
Entering of the widest diameter (biparietal diameter -measuring ear tip to ear tip across the top of the baby’s head) of the foetal presenting part through the plane of the pelvis/pelvic inlet.
-> the widest part of the babies presenting part passes through the inlet
Explain DESCENT - one of the cardinal movements of labour?
- Movement deep into the pelvic cavity or the downward passage of the presenting part through the bony pelvis.
- When the occiput is at the level of the ischial spines, it can be assumed that the widest diameter of the baby’s head is engaged -descent occurs after this happens.
- During descent the foetus moves downward into the pelvic cavity
Explain FLEXION - one of the cardinal movements of labour?
- Foetal chin flexes to chest
- Occurs during descent because of the resistance of the soft tissues in the pelvis against the baby’s head.
- This resistance causes flexion of the head (chin to chest).
- This is when the smallest diameter of the baby’s head presents into the pelvis
Explain INTERNAL ROTATION - one of the cardinal movements of labour?
• Rotation of the fetal head from occiput transverse to occiput either in anterior or posterior position
As the head reaches the pelvic floor, it rotates sothat the sagittal suture is in the anteroposterior diameter of the outlet. This means that the shoulders will pass through the widest part of the pelvic inlet, which is from right to left.
Explain EXTENSION - one of the cardinal movements of labour?
- At the end of internal rotation when the baby is at the level of the vaginal introitus (opening).
- This is the point when the birth canal curves upward.Head, face and chin curve up under and past the pubic symphysis
- You can also think of this as when the occiput is just past the level of the pubic symphysis and when the head, face and chin curve under and past the pubic symphysis and are born.
- The baby is still in an antero-posterior position
Explain EXTERNAL ROTATION/RESTITUION - one of the cardinal movements of labour?
- There is a short pause during labour after the head is born. During this pause, the baby needs to rotate from a face-down position to facing either one of the mother’s inner thigh’s
- This movement aka restitution, is necessaryfor the shoulders to fit under the pubic arch. Remember that the widest space in the pelvic outlet is in the anterior-posterior position.
- When the head is delivered in the ideal position, (either left occiput transverse or right occiput transverse), the baby’s shoulders are positioned anterior-posterior (AP) which is the widest diameter of the pelvic outlet.
- This is the point when you would notice a shoulder dystocia.
Explain EXPULSION - one of the cardinal movements of labour?
- Once the shoulders are positioned AP, the anterior shoulder (under the symphysis pubis) will deliver first followed by the posterior shoulder.
- Although this stage is often completed naturally, gentle traction is applied by pulling the head of the foetus downwards along the axis of the pelvis –this will aid in releasing the anterior shoulder
- After this, gentle traction is applied upwards to deliver the posterior shoulder
- The foetus is then placed on mums abdomen while drying occurs.
What does the LATENT phase in the first stage of labour include?
Early Latent phase
- last up to 20 hours
- irregular contractions
- cervix open to 3cm
Late latent phase
- Then regular contractions
- occur 3 - 5 mins
- cervix dilates up to 6cm
What does the ACTIVE phase in the first stage of labour include?
- intense contraction
- cervix opens up to 6-10cm
What is the second stage of labour?
The pushing phase.
Relies on the 3 p’s - Power/Passenger/Passage
define labour?
Normal process by which the foetus, placenta and membranes are expelled through the birth canal.
What are the theories around the onset of labour?
Hormonal
- oxytocin theory
- prostaglandin
- fetalsteroids
- oestrogen/progesterone
Mechanistic
Environmental
what are the premonitory signs of labour?
- Braxton Hicks Contractions
- Increased pelvic congestion / pressure
- Decent of foetus into pelvis
-Relaxed pelvic floor
–frequency of urine
–Stress incontinence
- Cervical effacement; Loss of operculum (Show)
- Static weight or weight loss
- Rupture of the membranes
What happens during the first stage of labour?
- Normal physiological process!!
- Marked by the onset of painful, regular uterine contractions
- Results in progressive effacement & dilation of the cervix
–> From 0cm to full dilation of 10 cms.
What are the 2 different types of labour?
True labour
Spurious labour
What is true labour?
Progressive dilatation and effacement of the cervix
Contractions -regular –increasing frequency & intensity
For many, discomfort radiates from back to lower abdomen
Pain is not relieved by ambulation
Descent of head