1. Mechanism of labour in breech
Amarendra B. Singh
090201263

2. Positions
* Left sacro-anterior.
* Right sacro-anterior.
* Right sacro-posterior.
* Left sacro-posterior.
* Left and right sacro- transverse (lateral).
* Direct sacro-anterior and posterior.
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4. Mechanism of labour
• Delivery of the breech (Buttocks and lower
limbs)
• Delivery of the shoulders and arms
• Delivery of the head
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5. Delivery of lower limbs and
buttocks
• Engagement
• Descent
• Flexion
• Internal rotation
• Birth of Buttocks
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6. Delivery of the buttocks
* The engaging diameter is the
bitrochanteric diameter 9.5cm which
enters the pelvis in one of the oblique
diameters.
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7. The anterior buttock meets the pelvic floor
first so it rotates 1/8 circle anteriorly .
* The anterior buttock hinges below the
symphysis
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8. and the posterior buttock is delivered first by
lateral flexion of the spines followed by the
anterior buttock.
* External rotation occurs so that the sacrum
comes anteriorly.
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9. Delivery of shoulders and arms
• Engagement
• Descent continuous
• Internal rotation
• Birth of shoulders
• Restitution
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10. Delivery of the shoulders
* The shoulders enter the same oblique
diameter with the bisacromial diameter 12
cm (between the acromial processes of
the scapulae).
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11. • The anterior shoulder meets the pelvic
floor first, rotates 1/8 circle anteriorly,
hinges under the symphysis, then the
posterior shoulder is delivered first, the
baby is then lowered and the anterior
shoulder and arms pass out under the
symphysis.
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12. Birth of after coming head
• Engagement
• Descent
• Flexion
• Internal rotation
• Birth of the head
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13. • Descent and Engagement: The head
enters the pelvis in the left oblique
diameter. The occiput is in the right
anterior quadrant of the pelvis.
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14. • Flexion: It is important that flexion is
maintained.
• Internal rotation: The head strikes the pelvic
floor and rotates internally so that sagittal
suture comes to lie in anteroposterior
diameter.
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15. • Birth of the head by flexion: The nape of
the neck pivots under the symphysis and
the chin, mouth, nose, forehead, bregma,
and occiput are born over the perineum by
a movement of flexion.
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