The placenta is an organ that develops during pregnancy. It transports nutrients and oxygen from mother to baby and removes the baby’s waste. In a normal pregnancy, the placenta attaches to the wall of the uterus until birth (1). After the baby is born, it naturally separates from the uterine wall and exits the body through the birth canal.
Placenta accreta is a condition in which the placenta has grown deeply into the uterine wall. For this reason, it doesn’t separate from the uterus properly during labor and delivery. If improperly managed, placenta accreta can cause severe hemorrhages, which can be life-threatening for mother and baby. Therefore, women who have been diagnosed with placenta accreta are considered to have a high-risk pregnancy.
There are other complications in which the placenta becomes abnormally attached to the uterine wall: placenta increta, when the placenta penetrates the uterine wall and attaches to the uterine muscle, and placenta percreta, when the placenta pushes through the uterine wall altogether and attaches to a different organ. Roughly 1 in 2,500 pregnancies will experience one of these three types of placental abnormalities (1).
Signs and symptoms of placenta accreta
Women who have placenta accreta may not experience any signs or symptoms during pregnancy. Some women may experience bleeding, any amount of which should be reported to your doctor as soon as possible. Bleeding during the third trimester is the main symptom of placenta accreta (1).
Risk factors for placenta accreta
Women are more likely to have placenta accreta if they have experienced:
- Uterine scarring from previous cesarean deliveries: Multiple cesareans have been present in over 60% of cases of placenta accreta.
- Previous uterine surgery
- Multiple pregnancy
- Advanced maternal age
- Placental placement issues: If the placenta partially or completely covers the cervix or sits lower in the uterus, the risk of placenta accreta increases (2).
- Previous birth: The chances of placenta accreta increase with the number of deliveries a woman has had (2).
Placenta accreta diagnosis
Placenta accreta is commonly diagnosed during a routine ultrasound. However, If suspected, a physician can order an ultrasound at any point during the pregnancy.
The following complications can occur as a result of placenta accreta:
- Hemorrhage: Because the placenta is attached to the uterine wall in placenta accreta, the separation can cause heavy bleeding, or hemorrhaging in the mother. A hemorrhage can lead to a severe drop in blood pressure and life-threatening blood loss.
- Disseminated intravascular coagulopathy: A condition that stops the blood from clotting the way it normally should.
- Premature delivery: Placenta accreta can lead to an early delivery, which can have its own set of complications and puts the baby at a higher risk of many conditions.
- Lung failure or kidney failure: Severe bleeding can lead to lung failure or kidney failure (2).
Placenta accreta management
Placenta accreta should ideally be diagnosed during the prenatal period (2). A team of medical professionals can then plan a safe delivery and discuss the process with the patient. The doctor will likely plan to manage the condition by trying to get the patient to term through rest and monitoring. Placenta accreta will usually be managed with a planned cesarean delivery and a skilled surgical team who works to remove the placenta and vessels from the uterine wall. The delivery plan should optimize the outcomes for mother and baby. Occasionally, the removal of the placenta may involve a hysterectomy, or the removal of the uterus.
Placenta accreta and hysterectomy
If a hysterectomy is deemed necessary by your doctor, the doctor will proceed with the removal of the uterus during the cesarean delivery. After delivering the baby, the doctor will remove the uterus with the placenta still attached. This will prevent severe bleeding. It’s important to note that, after a hysterectomy, the patient will not be able to become pregnant.
- “Placenta Accreta: Symptoms, Risks and Treatment.” American Pregnancy Association, 4 Apr. 2017, americanpregnancy.org/pregnancy-complications/placenta-accreta/.
- Placenta accreta. (2018, June 05). Retrieved January 7, 2019, from https://www.mayoclinic.org/diseases-conditions/placenta-accreta/symptoms-causes/syc-20376431