The course and conduct of normal labor and delivery. Emilia Brzezińska Division of Perinatal Medicine. A definition of labor. Progressive dilatation of the uterine cervix in association with repetitive uterine contractions. Spontaneous or induced Term or preterm. Important terms.
Division of Perinatal Medicine
Progressive dilatation of the uterine cervix in association with repetitive uterine contractions.
Spontaneous or induced
Term or preterm
Lie- relationship between the long axis of the fetus and that of the mother (longitudinal, transverse or oblique).
Presentation- the fetal part that lies closest to the pelvic inlet (cephalic - vertex, face; breech; shoulder).
Attitude- relationship of the fetal parts to each other, usually head and trunk (flexion or extension of the neck).
I - shortening and dilatation of the cervix
II - delivery of the fetus
III - delivery of the placenta with the umbilical cord and membranes
IV - about two hours after delivery (inspection and surgical help)
I - shortening
II - dilatation of external os
III - dilatation of internal os
phases I, II and III occur together
The special labor mechanisms is due to asymmetry of the shape of both the fetal head and maternal pelvis.
Changes in the position of the fetal head are required for the average size fetus to accomplish passage through the birth canal.
The rotations are accomplished by the propulsive force of uterine activity.
(Data in each manual of obstetrics)
2. internal rotation
4. external rotation
movements of the headCardinal movements of labor
It is the descent of the largest transverse diameter of fetal head (BPD) to a level below the plane of the pelvic inlet.
Then the head is engaged.
Flexion (I movement of the head)- placement of the fetal chin on the thorax
Internal rotation (II movement)- rotation from the transverse position towards symphysis.
Begins at the level of maternal vulva
The fetal head is delivered by extension from the flexed to the extended position rotating around the symphysis pubis
After delivery of the head the forces exerted on the head by the maternal pelvic musculature are relived and the fetus resumes its normal face-forward position.
Its face begins to „look” at one of mother’s leg.
Delivery of the shoulders - first the anterior one (under the symphysis pubis) and then the posterior one.
The rest of the body is usually quickly delivered.
Continuous fetal heart rate and contractions monitoring (CTG) - external or direct
Fetal capillary scalp blood sampling