Step 1 : Engagement is the first movement of labor where the first part of the head enters the pelvic inlet.
Step 2 : Descent refers to the deeper movement of the head through the pelvic inlet with the widest diameter of the infant's head.
Step 3 : Flexion occurs during descent, where tissues of the pelvis create resistance as the head moves down the pelvic cavity and brings the infant's chin to the chest. This allows for the smallest part of the head to begin to push through pelvis and actively promote delivery of the baby.
Step 4 : Internal rotation occurs when the head continues to descend and comes in contact with the pelvic floor, which has resistant muscles. These muscles allow for the infant to rotate their head to allow their head and shoulders to move through the pelvic. Due to the broad shape of the sacrum, the head of the fetus must be rotated from occiput transverse to occiput anterior position, which means the infant must rotate from the sideways position so the anterior head faces the buttock of the mother.
Step 5 : Extension is the point where the head moves past the pubic symphysis, where it has to curve underneath the birth canal while the anterior head still faces the mother's bottom.
Step 6 : External rotation (or Restitution) occurs when the baby pauses after the head passes through the body. During this pause, the infant rotates itself sideways (facing the mother's thigh) to allow for the shoulder to fit though the birth canal.
Step 7 : Expulsion is the final step of labor. During this stage, the anterior shoulder moves past the birth canal first then the posterior shoulder. Once both shoulders are out, the baby is delivered through the birth canal completely.
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Step 2 : Descent refers to the deeper movement of the head through the pelvic inlet with the widest diameter of the infant's head.
Step 3 : Flexion occurs during descent, where tissues of the pelvis create resistance as the head moves down the pelvic cavity and brings the infant's chin to the chest. This allows for the smallest part of the head to begin to push through pelvis and actively promote delivery of the baby.
Step 4 : Internal rotation occurs when the head continues to descend and comes in contact with the pelvic floor, which has resistant muscles. These muscles allow for the infant to rotate their head to allow their head and shoulders to move through the pelvic. Due to the broad shape of the sacrum, the head of the fetus must be rotated from occiput transverse to occiput anterior position, which means the infant must rotate from the sideways position so the anterior head faces the buttock of the mother.
Step 5 : Extension is the point where the head moves past the pubic symphysis, where it has to curve underneath the birth canal while the anterior head still faces the mother's bottom.
Step 6 : External rotation (or Restitution) occurs when the baby pauses after the head passes through the body. During this pause, the infant rotates itself sideways (facing the mother's thigh) to allow for the shoulder to fit though the birth canal.
Step 7 : Expulsion is the final step of labor. During this stage, the anterior shoulder moves past the birth canal first then the posterior shoulder. Once both shoulders are out, the baby is delivered through the birth canal completely.
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