Newborn head molding (infiltration of the head of the fetus during labor)
In short, the ability of the head of the fetus to change its shape to adjust to the mother’s pelvis to be passed. This ability has the greatest value in the progress of labor and the fall of the head through the birth canal.
The bones of the head are loosely connected by a membrane. There is a space between the bones. This allows changes in the relationship between them if any pressure on the head appears. By the pelvis, the bones can become closer or even stay away from each other. Side relations – side-to-side between the head bones can also change, one bone can cover the other bones. We can call it as “overlapping”, the frontal os and occipital os shift below the parietal os.
The parietal Os which is under pressure is greater than the promontory, so it will shift under the front os parietal. The factor helps moulage (newborn head molding) is the softness of the head bones. Compression in one direction will be followed by the expansion in the other direction so that the actual head volume is not reduced. If moulage is not too heavy and occurs slowly it will not cause damage towards the brain.
Infiltration is an important indicator of how far the fetus’s head can adjust to the single hard part of the pelvis. The greater of the degree in infiltration (overlap between the head bones), the more the risk of pelvic head disproportion is indicated. The inability to accommodate or disproportion is indicated by the degree of infiltration or overlapping (molasses) of the head bones which infiltrate each other.
These are also difficult to separate. If we find a suspicion of pelvic disproportion, it will be important to keep the condition of the fetus and the progress of labor. Do appropriate initial relief actions and refer the mother’s hand signs of pelvic bone disproportion to the adequate medical facilities. Every time you check in, keep the value of infiltration of the fetal head. Further, note in the appropriate tables under the amniotic fluid strip on the partograph sheet.
Infiltration of the fetal head bone is indicated by a symbol:
0: Separate fetal head bones and sutures can be easily felt
1: Bones – touched fetal head bones
2: Bone – overlapped fetal head bones, but can still be separated
3: Bone – overlapped fetal head bones and can not be separated
An assessment of fetal head reduction is carried out by mixing the proportion of the lower part of the fetus still at the edge of the symphysis and can be measured by five examiner fingers. The upper part of the symphysis is the proportion that has not entered the upper pelvis. While its side is not palpable indicating the extent to which the lowest part of the fetus has entered the pelvic cavity.
- 5/5 if the lower part of the fetus is entirely palpable over the pubic symphysis
- 4/5 if a part (1/5) of the lowest part of the fetus has entered the pelvic floor
- 3/5 if partially (2/5) the lowest part of the fetus has entered the pelvic cavity
- 2/5 if only a portion of the lower part of the fetus is still above the symphysis and 3/5 has passed through the middle of the pelvic cavity (the head is unable to move)
- 1/5 if only 1 or 5 fingers can still feel the lowest part of the fetus above the symphysis and 4/5 parts have entered the pelvic cavity
- 0/5 if the lowest part of the fetus cannot be touched from the outside examination and the entire lower part of the fetus has entered the pelvic cavity
The change in head shape is due to compression to the lowest part of the fetus. While the lowest part of the fetus due to protruding diameter perpendicular to the lowest diameter of the part. For example at the position of occipito anterior, the diameter of suboccipitobregmatic is the lowest diameter. Then the head will extend to the diameter of the verticomentalis with protrusion up and down.
Below are some changes in the shape of the fetal head:
- Caput Succedaneum
Caput Succedaneum is a swelling of the local scalp formed from serum effusion. Pressure on the cervical circle causes back blood obstruction so that the scalp located inside the cervix becomes edema (swelling). Caput forms during labor and after the membranes rupture, or the cervix does not stick tightly to the head. Multiple positions depend on the position of the head. On the occiput anterior position, the head is formed at the vertex. That is the right of the sagittal suture on the left occipitoanterior and the right occiput anterior. When flexion becomes clearer in labor, the back of the vertex becomes the lowest part and the cap is formed in the area, slightly on the right or left side than before. So if the position is left occipitoanterior then the caput is located on the back of the right os parietal, and at right occipitoanterior on the back of the left os parietal.
The size of the succedaneum caput is an indication of the severity of the pressure applied to the head. Large caput shows heavy pressure from above and detainees from below. The biggest caput occurs because the pelvis is narrow after prolonged and difficult parturition, while small caput occurs due to uterine inertia.
On vaginal examination, the examiner must be careful in distinguishing between the head drop and headache. Often the cap is counted as a head drop, in fact, there are obstacles in the reduction of the head.
Caput is seen at birth, begins to disappear after birth and generally disappears completely after 24 to 36 hours.
Cephalhematoma is bleeding that occurs under the periosteum of one or more skull bones. Hematoma is located in one or sometimes both os parietal and its shape resemble caput succedaneum. Cephalhematomas are caused by trauma to the head bones, including:
- Pressure on the old head against the cervix, perineum or os pubis
- Damage due to leaves of forceps
- difficult of head rotation manually
- Rapid compression and relaxation of the forces acting from the head of the fetus, such as in precipitation (rapid delivery).
This injury can also occur in spontaneous normal labor. Since the bleeding occurs under the periosteum, the swelling is limited to the affected bone and later it does not cross the suture lines. this is one way to distinguish from the succedaneum caput. Swelling occurs within a few hours after birth, also because of its long absorption, the loss takes 6 to 12 weeks. Blood quickly settles on the edge and remains liquid in the middle. Occasionally, there is ossification of the blood deposits and causing deformities that persist in the head bone. Here, a baby’s health is not disturbed and the brain will not experience problems.
Meningocele is a protrusion of meninges like a hernia. Meningocele is a serious congenital deformity and must be distinguished from caput or cephalhematoma. Meningoceles are always located on the suture or fontanelle and become tense when the baby cries.