Introduction:
During normal delivery, mostly the baby will be in cephalic presentation; that is, the head of the baby will be positioned downward, facing the mother's back, the chin will be tucked towards the baby's chest, and the back of the head will enter the pelvis. Usually, most babies come in this position within the 32 to 36th week of pregnancy. Although other fetal positions might have some difficulties during delivery, this article explains different abnormal fetal positions.
What Does Abnormal Baby Position Mean?
The direction in which the fetus faces the womb is called the position of the fetus. The safest position for a fetus just before delivery is facing the mother’s front of the body. However, it is considered abnormal when a fetus is headed down the birth canal with the face, feet, or shoulders first. Normally, the fetus may also be situated facing slightly right or left, with arms crossing the chest and a tucked chin; all other presentations and positions other than this are considered abnormal. An abnormal position or presentation also means that the pregnant woman is in for a difficult or long vaginal delivery or a cesarean delivery. Regardless of the situation and position, doctors and healthcare providers must be prepared to act whenever necessary.
How Is the Position Of the Baby Determined?
The position and presentation of the baby are often observed to avoid any complications during pregnancy. Each patient's risk factors are assessed by checking the patient's medical history for past pregnancies, obesity, hypertension, diabetes, and placenta previa. A physical exam, ultrasound scan, or other prenatal tests may help in detecting abnormalities in the shape of the uterus, the amount of amniotic fluid, the position of the placenta, or a narrow pelvis. The conditions like diabetes, hypertension, and obesity are also treated.
These tests can help to determine the fetal position of the medical personnel. To closely monitor the baby, frequent tests will be conducted in the late-term, around 36 weeks of pregnancy. Once the labor begins, a healthcare professional will get a more accurate sense of the baby's position by doing a vaginal examination. When the cervix is dilated enough, the health care professionals will insert their fingers into the vagina to feel the baby's skull as the baby moves down in the birth canal.
Furthermore, mothers should also pay close attention to the movement of the baby, and if any different movements are felt, it should be noted. Belly mapping is a technique that can help mothers to assess their baby's movement and obtain a sense of the baby's position as they near labor. For instance, by locating where strong kicks are felt, the position of the baby's legs and feet can be determined. Another landmark a mother can feel is a large, flat plane that can mostly be the baby's back.
What Are the Factors that Increase the Risk of Abnormal Fetal Positioning?
There are many factors that can increase the risk of abnormal fetal positioning, including:
- Early labor or a premature baby can cause abnormal positioning; the baby may not have had time to come in proper preparation for birth yet.
- If there are issues with the placenta, such as if the placenta is attached too low in the uterus or gets disconnected from the uterus before birth, it can prevent the baby from rotating and getting into the right position for birth.
- In the case of multiple pregnancies, it can be hard for each baby to get into a normal position because of the limited space created as the babies grow throughout the pregnancy.
- If there is an abnormality in the shape of the uterus, such as a partial septate uterus, there might not be enough shape for a baby to move into position for birth.
- Fibroids in the uterus can also create less space for baby movement.
What Is the Different Abnormal Position Of the Fetus?
The different abnormal positions of the fetus are as follows:
1) Occiput Anterior (Right and Left): The front of a baby's head is called the anterior portion, and the back is called the posterior portion. Two different positions can be referred to as the occiput anterior (OA) positions.
- Left Occiput Anterior (LOA) - This position is the most common in labor. The baby's head will be slightly off-center in the pelvis, and the back of the fetus's head will be toward the mother's left thigh.
- The Right Occiput Anterior (ROA) - This presentation is also common in labor. The back of the baby's head is slightly off-center in the pelvis, with the back of the baby's head facing toward the mother's right thigh.
The occiput anterior position does not cause any complications or additional labor pain during birth.
2) Occiput Transverse (Right and Left):
- Right Occiput Transverse (ROT) - When the baby is positioned facing outward toward the mother's left thigh, then the baby is said to be right occiput transverse. The right occiput transverse is halfway between an anterior and posterior position. If the baby moved from a posterior position to ROT, then it is a sign of a positive move toward the anterior position.
- Left Transverse Occiput (LOT) - When the baby is positioned facing out towards the mother's right thigh, then it is a left occiput transverse position. This position is midway between a posterior and anterior position. If a baby moves from a posterior position to the left occiput transverse, then it is a positive movement toward a normal position.
When a baby is in the LOT or ROT position during labor, there will be more pain and a slower progression.
3) Occiput Posterior (Right and Left): When the baby is facing forward, then it is referred to as the occiput posterior position.
- Right Occiput Posterior (ROP) - When the baby is positioned facing forward with a slight right tilt towards the mother's left thigh, it is called the right occiput anterior. This presentation causes more pain and slows down labor.
- Left Occiput Posterior (LOP) - When the baby is facing forward with a slight tilt to the left toward the mother's right thigh is called left occiput posterior. This presentation can slow the progression of labor and lead to more back pain.
Conclusion:
Abnormal presentation occurs when the baby is in a position other than the cephalic position, which is considered the normal position. The position of the baby is monitored from the beginning to avoid abnormalities during pregnancy because abnormal positions can cause complications during delivery. Cesarean delivery is often considered in women with abnormal fetal positions.
