Abnormal Placenta Conditions - Placenta Accrete
What is Placenta Accrete
Placenta accrete is an abnormal obstetric condition wherein, the placenta adheres to the uterine wall and becomes inseparable from it. During pregnancy, conception occurs in the endometrium termed as decidua. The deciua exists in three layers, which are, decidua basalis (the inner most layer which is closer to the baby), Decidua parietalis and Decidua capsularis. Placenta is a vital organ which supplies oxygen and nutrients to the growing baby and during normal pregnancy, placenta adheres to the decidua basalis layer. This makes the separation of the placenta from the uterine wall very easy after delivery. But during abnormal placentation, the placenta invades the uterine wall at varying degrees.
- Placenta accrete arises when the placenta crosses the decidua basalis and gets attached to the myometrium.
- Placenta increta is a condition where the placenta invades into the myometrium.
- Placenta percreta is a more sever condition arising when the placenta invades through the myometrium reaching the uterine serosa or in rare cases even the pelvic organs.
Who are at risk?
The increase in the incidences of placenta accreta is found to be related to the rising rate of cesarean deliveries. In fact, the chances of abnormal placentation have been found to be more in women having a prior history of cesarean deliveries. According to available statistics, the incidences of placenta accrete were 1 in 4,027 pregnancies in the 1970s, which rose to 1 in 2,510 pregnancies in the 1980s, finally reaching to 1 in 533 pregnancies during the period of 1982–2002. This increase is directly correlated with the increase in the rate to cesarean operations. Besides this, advanced maternal age and multiparity are also considered to be risk factors for placenta accrete. Any medical condition leading to damage in the myometrial tissue might lead to placenta accrete.
What are the physiological effects of placenta accrete?
For these patients, delivery becomes complicated as placenta fails to get separated from the uterus. Delivery in such a situation may lead to massive obstetric hemorrhage, that is, huge loss of blood from uterus or vaginal tract. This is a leading cause of maternal deaths and these patients might require blood transfusion. Placenta accrete often leads to emergency hysterectomy. Preterm birth and associated perinatal complications are also noticed.
How is placenta accrete diagnosed?
Diagnosis of placenta accrete is very essential as it facilitates the multidirectional management so that both child and mother can be saved. Ultrasonography and magnetic resonance imaging help in the detection of placenta accrete. The condition of accretion can be noticed very early during the first trimester itself through ultrasonography. In some rare cases, ultrasonography does not give accurate information as placenta lies on the posterior wall. However, none of these diagnostic tests give 100% assurance of placenta accrete to the clinicians.
Multidisciplinary Management of Placenta Accrete
A team of health care providers involving anesthesiologist, obstetrician, pelvic surgeon, oncologist, intensivist, maternal–fetal medicine specialist, neonatologist, urologist, hematologist, and interventional radiologist is require to handle the delivery of such patients. It is very essential that the health care providers have a ready access to the blood bank, as massive blood loss may be involved. Maternal hemoglobin levels should be tracked from time to time in case of advanced surgeries. An elective cesarean is planned and the patient should be informed about the potential need for hysterectomy in case of acute hemorrhage.
An efficient management and an experienced team of doctors can reduce the problems associated with palcenta accrete and protect the lives of both mother and child.
Russo M, Krenz Elizabeth I, et al. Multidisciplinary Approach to the Management of Placenta Accreta. 2011. Ochsner J. 11(1): 84–88.
Placenta accreta. Committee Opinion No. 529. American College of Obstetricians and Gynecologists. Obstet Gynecol 2012;120:207–11.
Garmi G and Salim R. 2012. Epidemiology, Etiology, Diagnosis, and Management of Placenta Accreta. Obstetrics and Gynecology International Volume 2012 , Article ID 873929