Vertex Presentation : Types, Positions, Complications and Risks

Overview 

When babies are about to enter the world, they are either in a vertex, breech, or transverse position. A vertex position means the baby is head-down in the pelvic region, which is the position a baby is required to be during vaginal delivery. 

This blog talks about the vertex position, complications, and the other types of positions the baby can be during delivery. 

What is the vertex position? 

As mentioned earlier, a vertex position is a baby’s position during vaginal delivery. The baby moves into the vertex position  between the 33^rd – 36^th week of pregnancy. In this position, the baby’s head comes out first through the vagina during delivery. However, it is vital to know that the baby can present with other positions like breech (feet-first position) or transverse (lying sideways) position. In such cases, the healthcare provider may suggest alternate birth plans to deliver the baby safely.   

How is a baby delivered in the vertex position?  

When a baby is in a vertex position, it moves through the birth canal and comes out through the vagina. Unlike other mammals that have wider birth canals, humans have smaller ones. Due to the tight space in the birth canal, the baby tends to flex their heads in different ways to fit into the area and enter the world. However, the chances of the baby changing position at the last minute reduce drastically when the baby’s head fits inside the birth canal. The baby can switch to a vertex position anytime during delivery even if it is in a breech or transverse position.

When to seek medical advice?

A pregnant woman can seek medical advice to clear any doubts or clarifications.

Request an appointment at Apollo Hospitals  

What are the other positions a baby may lie in the womb?  

As already mentioned, unborn babies may also assume breech or transverse positions in the womb. The following gives a detailed explanation of both.

Breech Position

In this position, the babies lie in the womb pointing their feet or buttocks toward the vagina of the mother. If the baby stays in a breech position even after 36 weeks of pregnancy, the healthcare provider may try External Cephalic Version (ECV) on the mother. ECV refers to external pressure on the belly to change the baby’s position to a vertex. This procedure is painful for the mother, but it is the safest way to keep the baby in place. In almost 50% of the cases, ECV works and assists the baby in moving into a vertex position. 

In case of vaginal bleeding, the irregular heartbeat of the baby, broken water, or multiple pregnancies, ECV is not recommended. Also, ECV should not be performed if the baby is bigger or smaller than usual, if the placenta is low or if the mother develops high blood pressure and organ damage. The healthcare provider may recommend C-section to deliver the baby in such cases. 

Transverse Position

The baby is lying across the uterus during delivery. The doctors may recommend an ECV procedure. If ECV fails, the healthcare provider may deliver the baby through a C-section .

Can complications happen even when the baby is in the vertex position? 

Even though the vertex position is the correct way a baby should lie during delivery, there are chances of complications. If the baby weighs more than 4.5 kg, it becomes challenging for the baby to manoeuvre out of the birth canal. The shoulders of heavy babies may face trouble moving down the canal. For such babies, doctors regularly conduct checks and are extra cautious during prenatal visits and at the time of birth. For babies above 5 kg, they may recommend alternate delivery options to avoid trauma for both the baby and the mother.  

What are the risks associated with the Breech and Transverse position of the baby? 

Breech and transverse positions can lead to many complications, such as the following:  

ECV issues: While the healthcare provider performs ECV to shift the baby’s position into a vertex position, it may rupture the amniotic sac or tear the placenta. Sometimes it may change the baby’s heartbeat or may induce early labour.  

Problems with breech birth: In the breech position, the baby isn’t able to push the cervical muscles of the mother to come out. Their shoulders or heads may get stuck or impaled by the mother’s pelvis. Also, the umbilical cord may enter the vagina before the baby, reducing blood and oxygen flow to the baby.    

Conclusion 

Vertex position is the right way a baby should lie in the womb during delivery. It doesn’t mean that vertex position does not cause complications. It is crucial to seek expert advice during pregnancy to clarify doubts and address all concerns.  

Frequently Asked Questions (FAQs)

Will the baby turn after being in a vertex position? 

Even when the baby is in the proper vertex position, there are chances of them turning to other positions. Expectant mothers with excess amniotic fluid may be a risk of a vertex-positioned baby suddenly becoming breech. Consult the healthcare provider and ask what can be done about keeping the baby in the proper position until delivery.  

How to know if a pregnant woman is having a vertex-positioned baby? 

All healthcare professionals are trained to feel the baby’s position with their hands. This method is known as Leopold’s moves, and they may help find if the baby has a positioned vertex. An ultrasound test also helps precisely find and confirm the baby’s position.