PLACENTA - ACCRETA, INCRETA, PERCRETA
Of all the body's organs, perhaps the one that best typifies
selfless service is the placenta. Most people give little thought
to the placenta, and few appreciate the marvelous complexity
and profound importance of this organ that is discarded and
forgotten after birth. While parents and loved ones rejoice at
the safe arrival of their newborn, few think of essential
services rendered by the placenta.
Until things go wrong.
During a normal pregnancy the placenta attaches to the surface of the endometrium and uterine wall. However a severe obstetric complication occurs when there is abnormally deep attachment of the placenta to the uterine wall. This condition is called placenta accreta, increta, or percreta, depending on the severity and deepness of the placental penetration. During Birth the placenta usually separates from the uterine wall relatively easily, however with placenta accreta, increta or percreta there is a great risk of haemorrhage during manual attempts to remove the placenta. Severe hemorrhaging can be life threatening. Other concerns for placenta percreta involve damage to the uterus or other organs during removal of the placenta. Hysterectomy is a common surgical intervention, but the results involve the loss of the uterus and the ability to conceive. Premature delivery and its complications is the primary risk factor for the baby.
The specific cause of placenta accreta is unknown, but it has been related to:
- placenta previa
- Previous cesarean deliveries: The risk of placenta accreta increases with the number of cesareans.
- Scar tissue
Placenta accreta is diffcult to diagnose and is rarely identified before birth. A Doppler ultrasound and MRI can lead t o the diagnosis of a suspected accreta. However, placenta accreta is rarely confirmed with certainty. Placenta accreta can cause some vaginal bleeding during the third trimester and elevated maternal serum alpha-fetoprotein levels in the second trimester, though this is also an indicator of many other conditions. During birth, placenta accreta is suspected if the placenta has not been delivered within 30 minutes of the birth. Usually in this case, manual blunt dissection or placental traction is attempted but can cause haemorrhage.
The safest treatment is a planned caesarean section and abdominal hysterectomy if placenta accreta is diagnosed before birth. If it is important to save the woman's uterus for future pregnancies then resection around the placenta may be successful.
There are multiple variants, defined by the depth of their attachment to uterine wall:
|Placenta accreta||Placenta attaches too deeply to the uterine wall and invades the myometrium but does not penetrate the entire thickness of the muscle.|
|Placenta increta||Occurs when the placenta further extends into the myometrium.|
|Placenta percreta||The worst form of the condition is when the placenta penetrates the entire through entire uterine wall. This variant can lead to the placenta attaching to other organs such as the rectum or bladder.|