As the labor progresses, near the end of pushing stage, sometimes mother and baby require additional support. This is called assisted birth. As the mother pushes, the doctor or nurse who attends to the delivery will carefully help the baby’s head out through the birth canal. Approximately one in eight women are found to undergo assisted birth, which is either vacuum assisted or forceps assisted.
What Is A Vacuum Assisted Birth?
The vacuum assisted birth is a procedure in which a Ventouse (vacuum extractor) is used to help the baby out of the birth canal. An instrument is attached to baby’s head through suction. This instrument is called a Ventouse. A cup which is usually made of soft plastic or metal is connected by a tube to the suction device. The cup firmly fits to the baby’s head. As the mother pushes through the next contraction, the doctor will gently apply a small amount of suction to the baby’s head and assist the baby’s head through the birth canal.
Vacuum assisted delivery is not performed in case of preterm delivery specifically if the delivery happens before the 34th week, as the baby’s head will be too soft during that time.
When Does One Need A Vacuum Assisted Birth?
The vacuum assisted delivery is recommended if:
- The mother is physically exhausted after pushing for a long time as in case of a prolonged labor
- The baby is in a difficult position to deliver naturally. This often happens if the mother has received an epidural. Epidural not only makes the mother deliver painlessly, it also makes the mother feel less contractions than usual thus making pushing ineffective. It also affects the action of the pelvic muscle that helps to turn the head and shoulder of baby into the preferred position during delivery
- The mother has some health issues that require her to stress less and therefore has to limit the time of pushing
- The baby is distressed. The baby may not be receiving enough oxygen which can increase the risk of brain damage
The vacuum assisted birth should be planned only if the hospital has the facility to carry a C-section. This is because if the vacuum assistance fails, C-section might be the only option.
Types Of Ventouse Cup Or Vacuum Extractors
There are different types of ventouse which vary in size and material which is used for the ‘cup’ portion of the instrument. The selection of the size and type of the cup depends on several factors like:
- The size of baby’s head
- The position of baby’s head
- How far has baby’s head come down the birth canal?
The most common type of vacuum extractors are:
- Metal cup: As the name implies, the cup is made of metal. It is mostly mushroom shaped. Diameter of this cup varies from 40 to 60 mm. The metal cup is used when baby’s head is higher in the birth canal. This type of vacuum extractor is used for more difficult delivery like when baby’s head is deflexed (brow presentation) or in occiput posterior (OP) position (back of baby’s head facing mother’s back) or the baby is distressed. Also, metal cup can be used when mother is not fully dilated (7cm dilation is enough).The benefit of using this type of ventouse is its higher success rate over the semi rigid cup and a soft cup.The disadvantage is that it increases the chances of fetal scalp injury
- Semi-rigid cup: This type of suction cup is made from flexible plastic. This is softer than the metal cup and more rigid than the soft cup. Semi rigid cup is used in similar conditions as the metal cup.The benefit of using this cup is the lower chances of fetal scalp injury than the metal cup. The disadvantage of this type of suction cup is that it is less successful than the metal cup
- Soft cup: Made of hard, but flexible, rubber or silicone. It is used only if baby’s head is relatively low in the birth canal. The main disadvantage is its lower success rate. As said earlier, it can only be successful if baby is very low and little assistance is required to pull the baby’s head through the birth canal. However this cup is very difficult to correctly fit to baby’s crown if the baby is higher in the birth canal, or the baby is in OP position
When Is A Vacuum Assisted Birth Possible?
There are certain prerequisites for the possibility of vacuum assisted birth. Some of them are:
- The water should be broken
- The cervix should be dilated at least 7cm
- Baby should be in a head down position only
- The crown of baby’s head should be reachable
- The head should be favorably down in the birth canal
When Is A Vacuum Assisted Birth Not Recommended?
The vacuum assisted birth is not recommended:
- If pregnancy has not crossed the 34th week mark
- If baby has undergone fetal scalp sampling (a procedure used to affirm whether fetal oxygenation is adequate)
- If baby’s head has not descended halfway through the birth canal
- If baby has some health condition with bleeding disorder like hemophilia
- If the pelvis of the mother is small for baby to come through
- The baby is not in a head down position
- If baby has a health condition affecting the skeletal strength
What Are The Risks Of Vacuum Assisted Birth To The Mother?
Most of the risk associated with the vacuum assisted delivery to the mother can happen during the normal vaginal birth too. Here are some common risks associated with vacuum assisted delivery to the mother:
- Pelvic organ prolapse: This happens when the vacuum birth weakens the ligaments and muscle that holds up the pelvic organs
- Urinary incontinence: Unintentional urine leakage can happen as a result of vacuum delivery. This can be rectified by physiotherapy
- Anal incontinence: If third or fourth-degree tear occurs during vacuum assisted delivery, anal incontinence (involuntary defecation) can happen
- Pain in perineum after delivery is common in vacuum assisted delivery
What Are The Risks Of Vacuum Assisted Birth To The Baby?
The baby born through vacuum assisted birth can have both significant and minor issues. Some of the commonly found risks are:
- Chignon: The cone shaped swelling that happens to the area where the suction cup is attached is called chignon. The swelling will resolve within two to three days. Besides, it is an indication of successful vacuum delivery
- Cephalohematoma: It refers to the accumulation of blood that is restricted to the space under the fibrous covering of skull bone. It is a relatively harmless condition and will resolve within a couple of weeks when baby’s body reabsorbs the blood
- Subgalealhematoma: This is considered to be the most dangerous complication of vacuum-assisted delivery. This potentially life threatening condition happens as a result of accumulation of blood in a relativity larger area of skull just beneath the scalp. A lot of blood can be lost this way. This happens due to significant damage that occurs in the veins under the scalp. This takes place when the suction is not strong enough to pull the baby’s head and instead it pulls the scalp
- Neonatal jaundice: It occurs when the level of bilirubin increases as a result of the breakdown of RBC. It is associated with vacuum assisted birth due to its increased chances of blood vessel damage. Though mostly this blood is reabsorbed by the baby’s body, the breakdown of blood results in increased production of bilirubin. As baby’s liver (which removes bilirubin from the body) is still developing, it may not be able to deal with the increased bilirubin, and as a result baby suffers with neonatal jaundice
- Intracranial hemorrhage: It is a very rare condition associated with vacuum assisted birth. However, it can lead to harmful long term side effects like speech loss, memory loss etc. depending on which part of the brain is affected. It is basically the hemorrhage that happens inside the skull
- Retinal hemorrhage: Due to the pressure placed on baby’s head, retinal hemorrhage, which is bleeding behind eyes, can happen after vacuum assisted birth. It usually resolves without further complications
- Clavicle fracture and injury to brachial plexus: This happens when the collarbones and brachial plexus get stuck or are wrongly placed in the birth canal and experience pressure as the vacuum pulls out baby’s head through the birth canal