What is the recommended management for a pregnant woman with suspected placenta percreta?

Management of Placenta Percreta

For suspected placenta percreta, the recommended management is planned cesarean hysterectomy at 34 0/7 to 35 6/7 weeks gestation with the placenta left in situ, performed at a Level III or IV maternal care facility with a multidisciplinary team assembled before delivery. 1, 2

Understanding Placenta Percreta

Placenta percreta represents the most severe form of placenta accreta spectrum (Grade 3E), where placental villi invade completely through the myometrium and into surrounding organs such as the bladder, bowel, parametria, or other pelvic structures. 2, 3 This creates a surgical emergency with dramatically worse outcomes than lesser degrees of abnormal placentation, including severe maternal morbidity in 82.1% of cases and mortality in 1.4%. 3

The pathophysiology involves a defect in the endometrial/myometrial interface that leads to failure of normal decidualization, allowing abnormally deep placental anchoring villi and trophoblast infiltration through the entire uterine wall. 1, 2

Risk Factor Assessment

The highest risk scenario occurs when placenta previa is combined with prior cesarean deliveries, with risk increasing from 7-fold after one cesarean to 56-fold after three cesarean deliveries. 4, 2 Placenta previa is present in 49% of placenta accreta spectrum cases, making it the single most important risk factor. 4

Additional risk factors include: 2

• Prior uterine surgery or curettage
• Asherman syndrome
• Advanced maternal age
• Multiparity

Antenatal Diagnosis and Planning

Antenatal diagnosis is critical because outcomes are optimized when delivery occurs at an appropriate facility before the onset of labor or bleeding. 1

Diagnostic approach:

• Transvaginal ultrasound is the primary diagnostic modality 5
• MRI should be obtained to better delineate the extent of placental invasion, particularly for posterior placenta or suspected percreta with organ involvement 3, 6
• Evaluation should include assessment for bladder invasion, cervical involvement, or parametrial extension 3

Preoperative coordination must include: 1, 5, 4

• Maternal-fetal medicine subspecialists
• Experienced pelvic surgeons (gynecologic oncologists preferred for Grade 3E disease) 3
• Urologic surgeons (especially if bladder involvement suspected)
• Interventional radiologists
• Obstetric anesthesiologists
• Neonatologists
• Blood bank with massive transfusion protocols
• ICU capabilities

Timing of Delivery

Delivery should occur at 34 0/7 to 35 6/7 weeks gestation for stable patients. 4, 2 This timing balances neonatal morbidity from prematurity against maternal hemorrhagic risk. 5

Do not delay delivery beyond 36 0/7 weeks, as approximately 50% of women with placenta accreta spectrum beyond 36 weeks require emergent delivery for hemorrhage. 5, 4

Administer antenatal corticosteroids when delivery is anticipated before 37 0/7 weeks. 5

Intraoperative Management

Critical surgical principles:

Never attempt manual placental removal—this causes catastrophic hemorrhage. 2, 3 The most accepted approach is cesarean hysterectomy with the placenta left in situ after delivery of the fetus. 1, 2

Surgical steps for Grade 3E disease with organ involvement: 3

1. Multidisciplinary team assembly with experienced pelvic surgeons present at delivery

2. Intraoperative assessment including:

   • Gross surgical field exposure and examination
   • Cystoscopy to evaluate bladder involvement
   • Consideration of careful intraoperative transvaginal ultrasound to determine extent of invasion 3

3. Adjunctive measures for high-risk cases:

   • Ureteral stent placement if bladder involvement suspected 5, 3
   • Consider uterine artery embolization combined with tranexamic acid for cases at high risk for pelvic hemorrhage 2, 3
   • Availability of resuscitative endovascular balloon occlusion of the aorta (REBOA) is ideal 3

4. Hemorrhage management:

   • Massive transfusion protocols using packed red blood cells, fresh frozen plasma, and platelets in fixed ratios 5
   • Maintain maternal temperature >36°C as clotting factors function poorly at lower temperatures 5, 2
   • Re-dose prophylactic antibiotics if blood loss exceeds 1,500 mL 5

Conservative Management Considerations

If safe primary hysterectomy is not feasible due to extensive organ involvement, consider conservative management with planned delayed hysterectomy at approximately 4 weeks from cesarean delivery in stable patients. 3 However, this approach has a 44% failure rate requiring hysterectomy in percreta cases and a 17% severe adverse complication rate. 2

Conservative management is associated with: 2

• Infection and febrile morbidity in 28% of cases
• Severe morbidity including sepsis, organ failure, or death in 6% of cases

Common Pitfalls to Avoid

Failure to diagnose placenta accreta spectrum in women with placenta previa and prior cesarean deliveries can lead to catastrophic hemorrhage. 5 Always evaluate these patients for placenta accreta spectrum. 5, 4

Attempting placental removal when accreta spectrum is encountered intraoperatively causes profuse hemorrhage and should be avoided. 4, 2

Delivering at a facility without adequate resources (blood bank, multidisciplinary team, ICU) significantly increases maternal morbidity and mortality. 1, 4

Postoperative Care

Intensive hemodynamic monitoring in the early postoperative period is essential, often best provided in an ICU setting. 5 Maintain vigilance for ongoing bleeding with a low threshold for reoperation if suspected. 5