Placenta Accreta: Symptoms, Causes, Treatment

What are the symptoms of placenta accreta?

Placenta accreta is a condition in which the placenta attaches itself too deeply into the wall of the uterus. This can lead to complications, especially during and after delivery. The symptoms of placenta accreta can vary, but they may include:

1. Absence of Symptoms During Pregnancy: Often, placenta accreta may not cause noticeable symptoms during pregnancy and may only be detected during a routine ultrasound or at the time of delivery.
2. Abnormal Bleeding During Pregnancy: Some women may experience abnormal vaginal bleeding during the third trimester, although this is not always the case.
3. Detection During Routine Ultrasound: Placenta accreta may be suspected if an ultrasound shows abnormalities in the placenta, such as its position or appearance.
4. Severe Bleeding During Delivery: The most significant symptoms often occur during delivery. If the placenta is unable to detach properly from the uterine wall, it can cause severe bleeding (hemorrhage) during or after delivery, which is a major concern associated with this condition.
5. Premature Delivery: In some cases, women with placenta accreta may go into labor prematurely.

Since placenta accreta is often asymptomatic during pregnancy, it is usually detected through imaging studies, such as ultrasound or magnetic resonance imaging (MRI), performed for other reasons or due to risk factors such as a history of cesarean section or placenta previa.

What are the causes of placenta accreta?

Placenta accreta occurs when the placenta abnormally attaches to the uterine wall, penetrating more deeply than it should. The exact cause of placenta accreta is not well understood, but several risk factors and conditions have been associated with its development:

1. Previous Uterine Surgery:

• Cesarean Section (C-section): The risk of placenta accreta increases with the number of previous C-sections. Scarring from previous surgeries may provide a pathway for the placenta to invade the uterine wall.
• Dilation and Curettage (D&C): Procedures that involve scraping the uterine lining, such as D&C, can increase the risk due to the resulting scar tissue.

1. Placenta Previa:

• This condition occurs when the placenta partially or completely covers the cervix. When combined with previous uterine surgeries, the risk of placenta accreta is higher.

1. Maternal Age:

• Older maternal age, particularly women over 35, is associated with an increased risk of placenta accreta.

1. Multiparity:

• Having multiple pregnancies (multiparity) is a risk factor, as the risk increases with the number of previous deliveries.

1. In Vitro Fertilization (IVF):

• Some studies suggest that pregnancies conceived via IVF may have an increased risk of placenta accreta.

1. Uterine Abnormalities:

• Congenital or acquired uterine abnormalities, such as fibroids or a bicornuate uterus, may predispose to abnormal placental attachment.

1. Previous Placenta Accreta:

• Women who have had placenta accreta in a previous pregnancy are at increased risk in subsequent pregnancies.

The combination of these factors, especially when multiple are present, increases the likelihood of placenta accreta. However, it can also occur in women without any identifiable risk factors.

How is the diagnosis of placenta accreta made?

The diagnosis of placenta accreta is typically made through a combination of imaging studies and clinical assessment, often during pregnancy. The key diagnostic methods include:

1. Ultrasound:

• Transabdominal and Transvaginal Ultrasound: These are the primary imaging techniques used to identify placenta accreta. They can help visualize abnormal attachment and invasion of the placenta into the uterine wall. Key ultrasound findings may include:
  • Loss of the normal hypoechoic (dark) space between the placenta and myometrium (uterine muscle).
  • Thinning or disruption of the uterine wall.
  • Presence of placental lacunae (irregular vascular spaces within the placenta).
  • Increased vascularity at the placental-myometrial interface.

1. Magnetic Resonance Imaging (MRI):

• MRI may be used to provide a more detailed view of the placental tissue and its relationship with the uterine wall and adjacent structures. MRI can be particularly useful if ultrasound findings are inconclusive or if there is a high suspicion of deeper placental invasion (e.g., placenta increta or percreta).

1. Clinical Assessment:

• A detailed obstetric history, including previous uterine surgeries and other risk factors, can raise suspicion for placenta accreta.
• If a patient has placenta previa, especially with a history of prior cesarean delivery, there is a higher index of suspicion for placenta accreta.

1. Doppler Ultrasound:

• Doppler ultrasound can assess blood flow in the placenta and surrounding tissues, helping to identify increased vascularity, which is suggestive of abnormal placental attachment.

The diagnosis is often confirmed during delivery when the placenta does not detach normally and is found to be more adherent to the uterine wall than expected. In some cases, the diagnosis may be made post-delivery based on the difficulty of removing the placenta and the associated bleeding.

Because placenta accreta can lead to severe complications, including significant bleeding, it is crucial for the diagnosis to be made as accurately as possible before delivery to plan for appropriate medical and surgical management.

What is the treatment for placenta accreta?

Placenta accreta is a condition where the placenta attaches too deeply into the uterine wall, making it difficult to separate during childbirth. This can lead to severe bleeding and other complications. The treatment and management of placenta accreta typically involve the following:

1. Prenatal Care and Monitoring: Early diagnosis and close monitoring during pregnancy are crucial. This is often done through ultrasound and MRI to assess the extent of placental invasion.
2. Planned Delivery: In cases where placenta accreta is diagnosed before delivery, a planned cesarean section (C-section) is usually scheduled, often between 34 and 37 weeks of gestation. This allows the medical team to prepare for potential complications.
3. Multidisciplinary Team: A team of specialists, including obstetricians, anesthesiologists, neonatologists, and sometimes vascular surgeons, is usually involved in managing the delivery and postpartum care.
4. Hysterectomy: In many cases, a hysterectomy (surgical removal of the uterus) is performed immediately after the C-section to control bleeding and prevent further complications. This is often necessary because trying to remove the placenta alone can lead to life-threatening hemorrhage.
5. Blood Transfusions: Due to the risk of significant bleeding, blood products are often prepared in advance, and blood transfusions may be necessary during or after surgery.
6. Medications: Medications to help control bleeding and stabilize the patient may be administered as needed.
7. Postoperative Care: Intensive monitoring and care in the hospital are required after surgery to manage any complications and ensure a smooth recovery.

In some cases, conservative management may be considered, where the placenta is left in place and monitored over time, allowing it to reabsorb gradually. However, this approach is less common and is generally reserved for cases with lower risk of complications.

The specific treatment plan for placenta accreta may vary based on the severity of the condition, the gestational age, and the overall health of the mother. Early diagnosis and a well-coordinated medical team are key factors in managing this condition safely.