Placenta Accreta

The placenta normally attaches to the uterine wall, however there is a condition that occurs where the placenta attaches itself too deeply into the wall of the uterus. This condition is known as placenta accreta, placenta increta, or placenta percreta depending on the severity and deepness of the placenta attachment. Approximately 1 in 2,500 pregnancies experience placenta accreta, increta or percreta.

What is the difference between accreta, increta or percreta?
The difference between placenta accreta, increta or percreta is determined by the severity of the attachment of the placenta to the uterine wall.

Placenta Accreta occurs when the placenta attaches too deep in the uterine wall but it does not penetrate the uterine muscle. Placenta accreta is the most common accounting for approximately 75% of all cases.

Placenta Increta occurs when the placenta attaches even deeper into the uterine wall and does penetrate into the uterine muscle. Placenta increta accounts for approximately 15% of all cases.

Placenta Percreta occurs when the placenta penetrates through the entire uterine wall and attaches to another organ such as the bladder. Placenta percreta is the least common of the three conditions accounting for approximately 5% of all cases.

What causes placenta accreta?
The specific cause of placenta accreta is unknown, but it can be related to placenta previa and previous cesarean deliveries. Placenta accreta is present in 5% to 10% of women with placenta previa.

A cesarean delivery increases the possibility of a future placenta accreta, and the more cesareans, the greater the increase. Multiple cesareans were present in over 60% of placenta accreta cases.

What are the risks of placenta accreta to the baby?
Premature delivery and subsequent complications are the primary concerns for the baby. Bleeding during the third trimester may be a warning sign that placenta accreta exists, and when placenta accreta occurs it commonly results in a premature delivery. Your healthcare provider will examine your condition and use medication, bed rest and whatever else necessary to help continue the pregnancy towards full term.

What are the risks of placenta accreta to the mother?
The placenta usually has difficulty separating from the uterine wall. The primary concern for the mother is hemorrhaging during manual attempts to detach the placenta. Severe hemorrhaging can be life threatening. Other concerns involve damage to the uterus or other organs (percreta) during removal of the placenta. Hysterectomy is a common therapeutic intervention, but the results involve the loss of the uterus and the ability to conceive.

What is the treatment for placenta accreta?
There is nothing a woman can do to prevent placenta accreta, and there is little that can be done for treatment once placenta accreta has been diagnosed. If you have been diagnosed with placenta accreta your healthcare provider will monitor your pregnancy with the intent of scheduling a delivery and using a surgery that may spare the uterus. It is particularly important to discuss this surgery with your doctor if you desire to have additional children.

Unfortunately, placenta accreta may be severe enough that a hysterectomy may be needed. Again, it is important to discussion surgical options with your healthcare provider.

Reprinted with permission from American Pregnancy Association