How is placenta accreta diagnosed

Having images reviewed by a radiologist and obstetrician who are experienced in identifying placenta accreta cases is important, although even then there can be some uncertainty. Women at high risk for placenta accreta should deliver with a team of experienced doctors who are prepared to manage an accreta and possible hemorrhage, even if accreta was not detected on ultrasound or MRI.

Fact: Many, if not most, women with placenta accreta also have placenta previa, have had a previous cesarean section, or both. A placenta previa always requires a cesarean section because the placenta is covering the cervix. Similarly, it is usually safest for women with placenta accreta who have had a previous cesarean section to deliver their baby via cesarean again.

This is especially true if the placenta is attached to the scar from the previous cesarean. The safety of labor with a placenta invading a cesarean section scar has never been evaluated, and the risk of rupture and major hemorrhage may be higher in this situation. If you do not have a placenta previa, you may be able to deliver vaginally.

However, this delivery may be complicated and is at a higher risk for hemorrhage. It is important to talk to an obstetrician with experience in this area before deciding on a vaginal versus cesarean delivery. Read more pregnancy and childbirth articles. Advertising revenue supports our not-for-profit mission. This content does not have an English version.

This content does not have an Arabic version. Diagnosis If you have risk factors for placenta accreta during pregnancy — such as the placenta partially or totally covering the cervix placenta previa or a previous uterine surgery — your health care provider will carefully examine the implantation of your baby's placenta.

More Information MRI. More Information Abdominal hysterectomy Amniocentesis C-section. Request an Appointment at Mayo Clinic. Share on: Facebook Twitter. Committee Opinion No. Tranexamic acid inhibits fibrin degradation and decreases bleeding complications and mortality in nonobstetric patients.

A large, recent, multicenter, international randomized clinical trial 74 showed a reduction in maternal death due to hemorrhage in cases of postpartum hemorrhage treated with tranexamic acid These results, as well as a lack of an increase in adverse events related to the use of tranexamic acid in pregnant or postpartum women, led some authorities to advise using tranexamic acid in cases of postpartum hemorrhage 75 The dose should be 1 g intravenously within 3 hours of birth.

A second dose may be given 0. Prophylactic tranexamic acid given at the time of delivery after cord clamping may reduce the risk of hemorrhage with placenta accreta spectrum. A recent meta-analysis showed decreased bleeding when tranexamic acid is given prophylactically at the time of cesarean delivery However, many of the studies had flawed designs or small numbers of patients, and rare but serious adverse events such as renal cortical necrosis have been reported with postpartum use It is noteworthy that women with this complication received considerably higher doses than are currently recommended 75 Nonetheless, prophylactic use is not currently advised for routine cesarean delivery and large studies are ongoing.

Prophylactic use in placenta accreta spectrum is unstudied. Several other clotting factors may help in cases of refractory bleeding. Although cryoprecipitate can be used to increase fibrinogen, fibrinogen concentrates may be preferred to reduce the risk of transmitting viral pathogens.

Efficacy of fibrinogen transfusion in the setting of obstetric hemorrhage or placenta accreta spectrum is unknown. Recombinant activated factor VIIa has been used in the management of severe and refractory postpartum hemorrhage. Downsides are a risk of thrombosis and considerable cost. However, there were six thromboses in fewer than patients 33 Thus, use in placenta accreta spectrum should be limited to posthysterectomy bleeding with failed standard therapy. Hypofibrinogenemia is the biomarker most predictive of severe postpartum hemorrhage In addition to standard assessment of fibrinogen levels, hypofibrinogenemia can be assessed in functional assays using viscoelastic coagulation testing such as thromboelastography or rotational thromboelastometry.

Results of these tests can be obtained quickly, and detection of hypofibrinogenemia by rotational thromboelastometry predicts the severity of postpartum hemorrhage A systematic review also noted that use of these tests reduced bleeding and transfusion, but not morbidity or mortality, in nonobstetric hemorrhage The usefulness of rotational thromboelastometry specifically in placenta accreta spectrum is uncertain but has recently been shown to reduce mortality in trauma surgery and other surgical specialties.

Should uncontrolled pelvic hemorrhage ensue, a few procedural strategies are worthy of consideration. Hypogastric artery ligation may decrease blood loss, but its efficacy has not been proved and it may be ineffective because of collateral circulation. In addition, hypogastric artery ligation can be difficult and time consuming, although it can be easily performed by experienced surgeons. The use of interventional radiology to embolize the hypogastric arteries in cases of persistent or uncontrolled hemorrhage may be useful.

Interventional radiology is especially helpful when there is no single source of bleeding that can be identified at surgery.

However, it can be difficult to safely perform in unstable patients and the equipment and expertise are not available in all centers. Other methods to address severe and intractable pelvic hemorrhage include pelvic pressure packing and aortic compression or clamping. Pelvic packing, although not standard management, can be highly effective for patient stabilization and product replacement when experiencing acute uncontrolled hemorrhage.

Packing may be left in for 24 hours with an open abdomen and ventilatory support to allow for optimization of clotting and hemostasis. Aortic clamping is likely best reserved for experienced surgical consultants or heroic measures given the potential risk of vascular-related complications from this approach.

Several other factors should be considered in the setting of hemorrhage and placenta accreta spectrum. Acidosis also should be avoided. If blood loss is excessive, often defined as estimated blood loss of 1, mL or greater, prophylactic antibiotics should be re-dosed Laboratory testing is critical to the management of obstetric hemorrhage. Baseline assessment at the initiation of bleeding should include platelet count, prothrombin time, partial thromboplastin time, and fibrinogen levels, which are normally elevated in pregnant women.

Rapid and accurate results can facilitate transfusion management, although the massive transfusion protocol is not based on laboratory studies. Thus, developing a protocol that allows for rapid results from a centralized laboratory or having point of care testing on the labor and delivery unit or in the general operating room is desired.

As with any case of uncontrolled hemorrhage, the following are key concepts to remember: treat the patient based on clinical presentation initially and do not wait for laboratory results, keep the patient warm, rapidly transfuse, and when transfusing in the setting of acute hemorrhage, be sure to transfuse packed red blood cells, fresh frozen plasma, and platelets in a fixed ratio.

Given the extensive surgery, placenta accreta spectrum patients require intensive hemodynamic monitoring in the early postoperative period. This often is best provided in an intensive care unit setting to ensure hemodynamic and hemorrhagic stabilization. Close and frequent communication between the operative team and the immediate postoperative team is strongly encouraged.

Postoperative placenta accreta spectrum patients are at particular risk of ongoing abdominopelvic bleeding, fluid overload from resuscitation, and other postoperative complications given the nature of the surgery, degree of blood loss, potential for multiorgan damage, and the need for supportive efforts.

Continued vigilance for ongoing bleeding is particularly important. Obstetricians and other health care providers should have a low threshold for reoperation in cases of suspected ongoing bleeding.

Pelvic vessel interventional radiologic strategies may be useful, but not all cases are amenable to these less invasive approaches and their use should be considered on a case-by-case basis. Clinical vigilance for complications such as renal failure; liver failure; infection; unrecognized ureteral, bladder, or bowel injury; pulmonary edema; and diverse intravascular coagulation is warranted. Lastly, attention to the small but real possibility of Sheehan syndrome also known as postpartum pituitary necrosis is warranted given the clinical scenario and the potential for hypoperfusion.

Despite antenatal diagnosis of placenta accreta spectrum and extensive delivery planning, it is possible that a patient may develop unexpected complications that may or may not be related to placenta accreta spectrum and that require an unscheduled delivery. Sometimes placenta accreta spectrum is unexpectedly recognized at the time of cesarean delivery, either before the uterine incision optimal or after the uterus is opened, the fetus is delivered, and attempts to remove the placenta have failed.

It is also possible to make the diagnosis of placenta accreta spectrum after vaginal delivery. The level and capabilities of the response will vary depending on local resources, timing, and other factors. It is important, however, that all facilities performing deliveries have considered the possibility of a case of placenta accreta spectrum and have plans in place to manage or rapidly stabilize patients in anticipation of transfer to a higher level facility per established institutional agreements 3.

With these caveats, a few general principles apply. If placenta accreta spectrum is suspected based on uterine appearance and there are no extenuating circumstances mandating immediate delivery, the case should be temporarily paused until optimal surgical expertise arrives. In addition, the anesthesia team should be alerted and consideration given to general anesthesia, additional intravenous access should be obtained, blood products should be ordered, and critical care personnel should be alerted.

If available, cell salvage technologies should be brought into the operative suite. Patience on the part of the primary operative team is key, and they should not proceed until circumstances are optimized. If mobilization of such a team is not possible, consideration of stabilization and transfer is appropriate, assuming maternal and fetal stability.

Many of the same principles apply when placenta accreta spectrum is inadvertently discovered with the uterus already open immediately after delivery. Once the diagnosis of placenta accreta spectrum is established and it is clear that placental removal will not occur with usual maneuvers, then rapid uterine closure and proceeding to hysterectomy as judiciously as possible should be considered.

Mobilization of appropriate resources should occur concurrently with ongoing hysterectomy in conjunction with the operating room nursing staff and anesthetic team. If the patient is stable after delivery of the fetus and the center is unable to perform the hysterectomy under optimal conditions, transfer should be considered. Temporizing maneuvers, packing the abdomen, tranexamic acid infusion, and transfusion with locally available products should be considered.

Uterine preservation , referred to here as conservative management, is usually defined as removal of placenta or uteroplacental tissue without removal of the uterus.

Expectant management is defined as leaving the placenta either partially or totally in situ. Because placenta accreta spectrum is potentially life threatening, hysterectomy is the typical treatment. Consideration of conservative or expectant approaches should be rare and considered individually. Major complications of treatment of placenta accreta spectrum are loss of future fertility, hemorrhage, and injury to other pelvic organs.

To reduce these complications, some have advocated conservative or expectant management in patients with placenta accreta spectrum 83 As defined previously, conservative management is removal of the placenta or uteroplacental tissue without removing the uterus. For patients with focal placental adherence, removal of the placenta by either manual extraction or surgical excision followed by repair of the resulting defect has been associated with uterine preservation in some cases Although randomized trials that compared hysterectomy to this approach are not available, it is apparent that blood loss is significantly less in a patient with a small defect using this approach.

In patients with too large a defect to subsequently repair, there are data that suggest that en bloc removal of the entire uteroplacental defect followed by uterine closure results in reduced blood loss and maintains potential fertility It is noteworthy that these conservative approaches have been reported only in small numbers of cases and it is unclear that all the patients included actually had placenta accreta spectrum.

Accordingly, efficacy remains uncertain. In patients with more extensive placenta accreta spectrum, expectant management is considered an investigational approach. With expectant management, the cord is ligated near the placenta and the entire placenta is left in situ, or only the placenta that spontaneously separates is removed before uterine closure.

Data are limited to case series when evaluating expectant management. In the larger series, those with successful expectant management had a median time to placental involution of Of the 36 patients who required hysterectomy, 18 were primary failures, occurring within 24 hours of primary cesarean, and 18 were delayed failures, occurring more than 24 hours after delivery All early failures and the majority of secondary failures were secondary to increased bleeding.

The degree of success with expectant management , defined as leaving the placenta in situ, of placenta accreta spectrum appears to correlate with the degree of placental attachment abnormality. Although these outcomes with expectant management are promising, it is unclear that these women truly had placenta accreta spectrum because successful cases had no histologic confirmation; in general, case series of expectant management included far fewer women with traditional risk factors such as previa and prior cesarean deliveries than cases reported using planned cesarean hysterectomy Thus, the chance of favorable outcomes may be overestimated.

Taking these limited published data together, and the accepted approach of hysterectomy to treat placenta accreta spectrum, conservative management or expectant management should be considered only for carefully selected cases of placenta accreta spectrum after detailed counseling about the risks, uncertain benefits, and efficacy and should be considered investigational. In addition to leaving the placenta in situ, investigators have used adjunctive measures to diminish blood loss, hasten placental reabsorption, or both.

It's also possible for the placenta to invade the muscles of the uterus placenta increta or grow through the uterine wall placenta percreta. Placenta accreta is considered a high-risk pregnancy complication. If the condition is diagnosed during pregnancy, you'll likely need an early C-section delivery followed by the surgical removal of your uterus hysterectomy.

Placenta accreta often causes no signs or symptoms during pregnancy — although vaginal bleeding during the third trimester might occur. Placenta accreta is thought to be related to abnormalities in the lining of the uterus, typically due to scarring after a C-section or other uterine surgery. Sometimes, however, placenta accreta occurs without a history of uterine surgery. Mayo Clinic does not endorse companies or products.