mechanisms Flashcards
(16 cards)
How should you introduce yourself to Ana?
Introduce yourself and confirm Ana’s name. Explain that the supervisor has asked to discuss mechanisms of labour and ask if this is okay. Wash hands using 5 moments of hand hygiene and WHO 7 steps.
What approach will you take to deliver antenatal education?
An Assets Based approach, taking into account previous knowledge about mechanisms of labour.
What is the definition of the mechanisms of labour?
The process of the widest part of the fetus negotiating the widest part of the pelvis.
Describe the basic anatomy of the pelvis.
The pelvis is formed in two parts: the false pelvis (everything from the brim and above) and the true pelvis (everything from the brim and below).
What are the diameters of the pelvic brim?
- Anterior and posterior: 11 cm
- Oblique: 12 cm
- Transverse: 13 cm
Describe the pelvic cavity and its diameters.
The pelvic cavity extends from the brim, is almost circular, shorter at the front and longer at the back. All diameters are 12 cm.
What is the shape and composition of the pelvic outlet?
The pelvic outlet is diamond-shaped, formed by the coccyx, lower part of the symphysis pubis, and ligaments.
What are the diameters of the pelvic outlet?
- Anterior/Posterior: 13 cm
- Oblique: 12 cm
- Transverse: 11 cm
What happens during the descent stage of labour?
Descent begins differently for primigravida and multiparas, with the fetus descending towards the pelvic brim, known as engagement.
What is flexion in the context of labour?
Flexion occurs due to increased descent, where the baby tucks its chin to present smaller diameters.
What occurs during internal rotation in labour?
The fetus rotates from a transverse position to a more anterior position as it negotiates the pelvic cavity.
What is crowning in the labour process?
Crowning occurs when the largest diameter of the baby’s head has passed through the vulva and stays there.
Describe the extension phase during labour.
Extension occurs after crowning, where the neck pivots on the sub pubic arch and the baby’s head is born.
What is restitution in the labour process?
Restitution realigns the baby’s head and neck towards the maternal right after entering the pelvis.
What happens during external rotation of the head and internal rotation of the shoulders?
Both occur simultaneously as the shoulders adjust to the widest diameter for birth.
What is lateral flexion in the birth process?
Lateral flexion follows the curve of carus, assisting in the delivery of the baby through specific movements.
