Placenta Accreta

In many cases, placenta accreta may cause no symptoms. However, certain percentage of women may experience vaginal bleeding during the third trimester. Such emergency situation calls for immediate hospitalization followed by prompt initiation of treatment. Caesarean section for delivery of the baby and hysterectomy is often the treatment of choice in such cases.

Women who have undergone caesarean section in the past or have suffered from placenta previa or any uterine surgery, tests to determine placenta accreta for the current pregnancy may be carried out. The following diagnostic procedures are done to detect this condition:

• Blood work to determine the levels of alpha fetoprotein. Rise in levels of alpha fetoprotein is a strong indicator for placenta accreta.
• Imaging studies such as ultrasound, MRI and CT scan of the uterus is done to evaluate the positioning of the placenta [6]. If placenta accreta is present, the ultrasound examination would reveal a “moth-eaten” or “Swiss cheese” appearance to the placenta. The use of ultrasound data with a high suspicion of placenta accreta, history of previous caesarean sections and presence of placenta previa plotted in mathematical model may prove to be more effective in predicting placenta accreta preoperatively [7]. The antenatal diagnosis of placenta accreta may prompt the attending physician to prepare fresh whole blood before delivery to prevent lethal blood loss in patients [8].

Once placenta accreta is diagnosed during pregnancy, a treatment plan ensuring safe delivery of the baby is chalked out. In case of severe placenta accreta a caesarean section is done for delivery of the baby followed by hysterectomy to avoid complications to set in [9]. These placenta accreta cases are most common among patients with previous caesarean section scarring [10]. In such cases, the uterus is removed to prevent further complications to the mother. The procedures should be carried out in hospitals that have adequate facilities to handle severe complications.

A test known as maturity amniocentesis is done is cases when premature delivery is planned. This test measures the maturity of the heart and lungs of the baby so that the delivery can be done prior to completion of 38 weeks of gestation.

In rare cases the uterus is not removed, basically when the woman plans to get pregnant in future. However, such a decision may pose several health risks to the mother and the risk is seldom taken. It also gets worth mentioning that there is dearth of research studies that suggest an association between complications in future pregnancies if hysterectomy is avoided. It is therefore suggested that, women who wish to preserve their fertility should discuss the pros and cons with their health care provider.

The prognosis of placenta accreta is largely dependent on the time of diagnosis. If it has been diagnosed during pregnancy, then there is sufficient amount of time for effective management of the condition and counseling of the mother. However, if it is diagnosed during delivery, then women undergo caesarean section to deliver the baby followed by hysterectomy.

Appropriate planning can be made and emergency situation avoided if the diagnosis is made during pregnancy. This can also avoid complications from developing and allow for a better prognosis. Mothers who deliver in a tertiary hospital with a multidisciplinary team on standby may have a good prognosis [5].

Complications of placenta accreta include the following conditions:

• Heavy vaginal bleeding is one of the major life threatening complications of placenta accreta. In this, there is heavy blood loss due to disseminated intravascular coagulopathy. 
• Lung failure
• Kidney failure
• Premature delivery may be required as the labor begins early in such cases. In addition, if women experience bleeding during pregnancy, then the child may have to be delivered before time.

Placenta accreta occurs due to development of abnormalities in the lining of the uterine wall. This can be a result of scarring that develops due to previous surgical procedures concerning the uterus [2]. In addition, it is also thought that caesarean section is one of the major causative factors for placenta accreta [3]. A caesarean section causes scarring in the lining of the uterus especially those with retained uterine sutures from the previous operations leading to development of such a condition [4].

Research has pointed towards the fact that the increase in the rate of caesarean section deliveries also increases the risk of developing placenta accreta. It has also been estimated that placenta accreta occurred in about 1 in 533 pregnancies in the years 1982 to 2002. Statistics indicate a significant rise in the incidence of placenta accreta in the past few decades.

Under normal circumstances, the placenta attaches to the wall of the uterus for providing nutrients and oxygen to the developing fetus. During delivery, the placenta detaches itself from the uterine wall. In the condition of placenta accreta, either a part of the placenta or the entire placenta invades the uterine wall and grows deep inside it. This causes severe blood loss during the third trimester and even during delivery. Such a condition can also develop due to malformation or absent decidua (mucous membrane that lines the uterus).

There is no way to prevent placenta accreta. However, complications can be prevented if the condition is diagnosed during pregnancy so that an effective treatment plan can be carried out.

Placenta accreta is potentially a life threatening condition that develops when the placenta invades deep into the uterine wall [1]. In such a condition, it becomes difficult to separate placenta from the uterine wall which calls for an emergency surgical procedure.

Placenta accreta is becoming an increasingly common complication of pregnancy which can cause life threatening hemorrhage if hysterectomy is not done on time. When such a condition develops, the woman is taken for caesarean section followed by surgical removal of the uterus.

Definition

Placenta accreta is a condition characterized by abnormal attachment of the placenta to the uterus. It is a high risk obstetric condition, wherein the placenta invades deep into the uterine wall. Such a condition calls for severe complications to set in. With the increasing incidence of caesarean section, the incidence of placenta accreta is also increasing.

Cause

Scarring in the lining of the uterus is the major factor identified behind the development of placenta accreta. Caesarean section and other surgical procedures of the uterus are some of the risk factors for placenta accreta.

Symptoms

Heavy bleeding is the significant symptom of placenta accreta. In many cases, the condition produces no symptoms. Vaginal bleeding is experienced in the third trimester which requires immediate attention and immediate treatment to avoid unnecessary complications.

Diagnosis

Diagnosis of placenta accreta is done using imaging studies such as ultrasound, MRI and CT scan of the uterus. Ultrasound may reveal the actual features of the placenta which would help diagnose the condition. A blood test that reveals elevated levels of alpha fetoprotein is indicative of placenta accreta.

Treatment

Treatment depends on the severity of the condition. In many cases, premature delivery is done to protect both the baby and the mother from serious complications. Following this a hysterectomy would also be required.

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