Circumvallate Placenta – Causes, Symptoms, and Treatment

Circumvallate Placenta – Causes, Symptoms, and Treatment

The placenta plays a vital role during pregnancy, by providing the growing baby with oxygen and the nutrients needed for development. It forms during pregnancy and attaches itself to the wall of the uterus around six to ten days after conception. A healthy placenta is vital for a healthy pregnancy, as it ensures that the baby develops as normal. However, in some cases,  the placenta may not develop correctly, which could affect the baby’s growth. Placental abnormalities, such as circumvallate placenta, can affect the health of the growing baby. However, as a to-be mother, you should know that circumvallate placenta is a very rare condition and can be easily detected during an ultrasound. Read on to know more about this condition and how it can be managed.

What Is Circumvallate Placenta?

When the growth of the placenta results in an abnormal shape, it is called circumvallate placenta. Here, the chorionic plate of the placenta is too small, causing the membranes of the foetal side to double back during development. It occurs around the edges of the placenta. This will sometimes result in the foetus getting fewer nutrients.

There are times when doctors don’t notice this problem during pregnancy and would notice it only after delivery. Although the diagnosis is difficult, the condition can be detected during ultrasound scans conducted around 20 weeks of pregnancy.

How Is Circumvallate Placenta Different From a Normal Placenta?

The main difference between circumvallate placenta and a normal placenta lies in the shape. There are 2 sides to a placenta: a maternal side and a foetal side, both of which are separated by a thin membrane. In a normal scenario, these sides align perfectly with each other, allowing for blood and nutrients to flow from the mother to the foetus.

However, in the case of circumvallate placenta, the edges of the placenta curl up and fold towards the foetal side, causing it to appear smaller than the maternal side.This curve hinders the flow of blood and nutrients from the mother to foetus, which can affect development.

What Causes Circumvallate Placenta?

The exact reason for why this condition occurs and what causes it is not yet known to researchers. If you’ve been diagnosed with this condition, the best you can do is follow your doctor’s instructions, take rest, and eat healthy.

Who Can Get Circumvallate Placenta?

Circumvallate placenta has been found in women of all ages, races, and geographical locations. There is no real defining factor of who is more likely to get it. It has been seen that around 1% of expecting women are likely to develop it.

Circumvallate Placenta Signs and Symptoms

While circumvallate placenta does not always cause symptoms, some women do experience pregnancy issues that lead their doctors to feel like circumvallate placenta might be a possibility. Here are a few signs that you may have circumvallate placenta:

1. Slow Foetal Growth

When a mother has a circumvallate placenta, the growth of the foetus tends to be slower. If your doctor finds that your baby does not reach certain growth milestones during your regular check-ups, you will need to be tested to determine the cause. Usually, at this point, your doctor may try to rule out circumvallate placenta through an ultrasound. With a closer look, it can be confirmed if you have this condition or not.

2. Bleeding From the Vagina

During the first trimester, some women experience more bleeding from the vagina than is normal. A study concluded that vaginal bleeding was more common in women who had circumvallate placenta than in others. However, it is important to note that the study was conducted taking into account a small number of women, so it may not be a good representation of all women who develop circumvallate placenta.

3. Premature Rupture of Membranes

Premature Rupture of Membranes (PROM) is another possible sign of circumvallate placenta. PROM takes place with the premature rupture of the amniotic sac. When this occurs before labour, or before a woman has reached 37 weeks of gestation, it is known as the preterm premature rupture of membranes (PPROM). When PROM occurs along with vaginal bleeding, it is a possibility that a mother has developed circumvallate placenta.

4. Preterm Birth

In a preterm birth, a woman delivers her baby before 37 weeks of pregnancy have been completed. It is possible that if a woman gives birth before the full period of gestation, which is between 37-42 weeks, it could be a result of circumvallate placenta.

How Does Circumvallate Placenta Affect Pregnancy?

Circumvallate placenta can complicate your pregnancy in one or more of the following ways:

1. Placental Abruption

When the placenta is separated from the lining of the uterus too early, it is known as placental abruption. This can cause excessive  bleeding and put the mother and baby at risk.

2. Miscarriage and Premature Labour

If a circumvallate placenta is severe and not treated, the pregnancy could result in a miscarriage or the mother going into premature labour.

3. Oligohydramnios

When there is a decrease in the amount of amniotic fluid, it is known as oligohydramnios. Amniotic fluid is helpful to the baby as it forms a cushion around it. This fluid is also essential for foetal development and protecting the ever-important umbilical cord from any damage during pregnancy. Without the umbilical cord in peak condition, the transference of proper nutrients and oxygen might be hindered.

4. Increased Risk of Emergency C-Section

A study conducted in 2014 revealed that in 46.5% cases of women with circumvallate placenta, an emergency c-section was necessary for safe delivery of the baby. While there is no guarantee that this occurs in all cases, your doctor will keep a close watch for symptoms that demand the same.

5. Low Birth Weight

One of the most common problems faced by mothers who develop circumvallate placenta is that their babies are born with low weight at birth. This takes place due to the restricted or slow growth of the foetus, as a result of the abnormal shape of the placenta.

6. Chances of Requiring Neonatal Intensive Care

The same study mentioned in point 4 also reported that more than half (55.4%) of the infants born from mothers with circumvallate placenta  were admitted to a neonatal intensive care unit to ensure better health and development.


Circumvallate placenta is not easy to diagnose. However, there are times when doctors may notice that the placenta has formed abnormally during regular check-ups and ultrasounds. This is really the only way to diagnose circumvallate placenta.

Sometimes, if a mother happens to show some symptoms of circumvallate placenta, the doctor may do a deeper check to diagnose the issue. In other instances,  circumvallate placenta may be unknown until the time of delivery.If it is diagnosed before birth, doctors can help manage the condition better to avoid effects such as low birth weight.

Treating Circumvallate Placental Complications

Doctors cannot repair the placenta in case of circumvallate placenta. However, they can help women manage it. Here are some ways in which your doctor can help you cope with the complications that arise out of circumvallate placenta:

1. Intrauterine Restricted Growth

There is no treatment for this condition, but your doctor will be able to help you manage it. The development of the baby will need to be monitored a lot more than usual and you will be advised to ensure that your diet is well-balanced and packed with nutrients. You will also be asked to rest well and develop a healthier lifestyle. If you are a smoker, you will need to quit any substances containing nicotine or tobacco.

2. Placental Abruption

IV fluids may be administered to help with increasing blood pressure, if you lose too much blood as a result of the ruptured placenta. If it is too early for your baby to be born, bed rest is usually prescribed.

3. Pre-Term Birth

Pre-term birth is usually avoided unless needed. Unfortunately, there have been some cases where women have had to deliver the baby right away due to severe blood loss. Any situations that put either the baby or the mother’s life in danger will result in an emergency C-section.

4. Oligohydramnios

Women who have low amniotic acid will need a lot more monitoring. One possible treatment that may need to be administered is  “Amnioinfusion”. Here, fluid is placed inside the amniotic sac to replace lost fluid. By doing this, the risk of damage to the umbilical cord or hindrance to development of the lungs may be reduced.

Is Vaginal Delivery Possible in Case of Circumvallate Placenta?

Though there are plenty of situations when a mother may need to undergo an emergency C-section in the case of circumvallate placenta, this is not always necessary Circumvallate placenta outcomes vary from case to case.

Many mothers have been able to carry their babies to term and have had normal deliveries. If you are diagnosed with circumvallate placenta, the first thing that will happen is that you and your baby will be closely monitored. This is to ensure that everything is going smoothly.

The doctor  will only intervene if there is a reason to. Managing the case and trying to help things flow smoothly for a normal vaginal birth is always the first option.

Can It Be Prevented?

There is currently no real way to prevent circumvallate placenta as the cause is not yet known. The only thing that can be done is to make sure that mothers who have been diagnosed with this condition take very good care to follow the directions given to them by their doctor.


Circumvallate placenta is a very rare condition. The good news is that many mothers have managed to deliver their little ones with no real issues, despite the abnormality. In less fortunate cases, the condition leads to other complications that make normal delivery impossible. Circumvallate placenta risks the life of the mother and child if not managed well, so if you have been diagnosed, remember to consult with your doctor regularly and follow all instructions.

Following your doctor’s advice is the best thing that you can do for your baby’s health and for your health too. As there are no known causes of circumvallate placenta, there is no way to suggest how to prevent it from occurring. Your baby needs you to be in the prime of health, so make sure you keep a watch out for any concerns. This is the one way that pregnant women can hope for a problem-free pregnancy that results in a smooth delivery.


1. Celik. OY, Obut. M, Keles. A, et al.; Outcomes of pregnancies diagnosed with circumvallate placenta, and use of uterine artery pulsatility index and maternal serum alpha-fetoprotein for prediction of adverse outcomes.; European Journal of Obstetrics, Gynecology, and Reproductive Biology;; May 2021

 2. Taniguchi. H, Aoki. S, Kentaro. S, et al.; Circumvallate Placenta: Associated Clinical Manifestations and Complications—A Retrospective Study; PubMed Central;; November 2014

3. Lorene. T, Nandini. R, Candice. W, et al.; 432: Clinical significance of circumvallate placenta; American Journal of Obstetrics;; February 2017

4. Ricarda. D, Wolfgang. H, Michael. E, et al.; Circumvallate placenta and abnormal cord insertion as risk factors for intrauterine growth restriction and preterm birth: a case report; Case Reports in Perinatal Medicine; De Gruyter;; October 2020

5. Adanna. L, Andrew. D, Sarah. B, et al.; Prenatal Diagnosis of Circumvallate Placenta and Pregnancy Outcomes; Obstetrics & Gynecology;; April 2014

Also Read:

Placenta Previa in Pregnancy
Placenta Positions in Pregnancy
Calcification of Placenta during Pregnancy

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