Surgical Management of Placenta Accreta

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Written By Sydney Oesch

Episode Notes

  1. Placenta Accreta Spectrum (PAS): encompasses accreta, increta, percreta 

    1. Pathophysiology: abnormal attachment/invasion of placental trophoblast into myometrium

    2. Etiology: defect in endometrial-myometrial interface disturbs normal decidualization > deep placental anchoring villi, trophoblast infiltration

    3. Risk factors: prior cesarean delivery/uterine instrumentation, placenta previa, Asherman syndrome, advanced maternal age, multiparity, cesarean scar pregnancy

      1. Small proportion of patients develop PAS without traditional risk factors and etiology is unknown

    4. Incidence: rising w/ increasing rates of cesarean delivery/uterine instrumentation, most recent incidence 1/272 live births

    5. Sequelae of PAS: increased morbidity/mortality

      1. 1% perioperative mortality rate

      2. 80% rate of perioperative morbidity (hemorrhage, prolonged hospitalization, peripartum infection, amniotic fluid embolism, reoperation)

    6. Classification

      1. FIGO grades 1, 2, 3 correspond to placenta accreta, increta, percreta

        1. 3a = limited to uterine serosa; 3b = urinary bladder invasion; 3c = invasion of other pelvic tissue/organs

  2. Diagnosis

    1. Final diagnosis is pathologic. Preoperative suspicion based on risk factors and imaging findings, however suspicious cases may end up having a placenta deliver spontaneously, and patients with no suspicious findings can end up having PAS

    2. Preoperative diagnostic modalities include:

      1. Ultrasound:

        1. Concerning features: vascular lacunae, loss of hypoechoic zone between placenta and myometrium, decreased retroplacental myometrial thickness (esp if <1mm), abnormal uterine serosa-bladder interface, invasion of placenta into myometrium and beyond

          1. Doppler can demonstrate turbulent lacunar blood flow

        2. Timing of ultrasound w/ suspected PAS: 18-20w, 28-30w, 32-34w

      2. MRI: 

        1. Concerning features: dark intraplacental bands on T2-weighted imaging, bulging of placenta or uterus, disruption of placental-uterine interface, abnormal placental blood vessels

        2. MRI is NOT more sensitive or specific compared to ultrasound alone (sensitivity ranges between 75-100% in systematic review, specificity between 65-100%).

          1. As such, not recommended by ACOG or SMFM as preferred initial modality. May be useful in cases with posterior placenta or suspected percreta

    3. Labs/biomarkers: none yet on the market with sufficient sensitivity or specificity to use in clinical practice

  3. Standards of perioperative care

    1. Traditional standard of care is cesarean hysterectomy

    2. Should be delivered/managed at a level III+ maternal care system: access to interdisciplinary team w/ neonatal, critical care, obstetric specialists, well-stocked blood bank, anesthesia

      1. Understand specialty availability at delivering hospital: urology, IR, etc

    3. Delivery timing: ACOG recommends 34-35w6d

    4. Optimize preoperative anemia: oral and/or IV iron, transfusion if needed

      1. Understand blood bank at delivering hospital

    5. Non-standard perioperative techniques

      1. Preoperative ureteral stent placement: in a retrospective review, patients w/ preoperative ureteral stents had lower rate of GU injury

      2. Cystoscopy: consider to help delineate bladder involvement if suspicious

      3. Preoperative balloon catheters in hypogastric arteries: mixed results regarding impact on EBL. One small RCT showed no benefit with EBL. Risks include vascular injury, clot.

        1. NOT recommended as routine preoperative prep

    6. Intraoperative techniques/options for management of peripartum hemorrhage w/ suspected/diagnosed PAS

      1. Hysterotomy closure immediately after confirmed inability to deliver placenta

      2. Hypogastric/internal iliac artery ligation: 

        1. Ensure ligation distal to bifurcation of the posterior branch of the hypogastric/internal iliac artery (in some patients this may be 5cm after the bifurcation of the common iliac artery)

      3. IR embolization of internal iliac artery: can be done intraoperatively, immediate after delivery

        1. Useful especially with bleeding without an isolated/identifiable source

        2. Associated with decreased EBL, need for blood transfusion and massive transfusion protocol. 

        3. Associated with prolonged operative times, increased need for general anesthesia, equivalent postoperative complications and neonatal outcomes

      4. IR embolization of uterine artery

      5. Intraoperative infusion of TXA

      6. Pelvic pressure packing: helpful if diffuse oozing/concern for coagulopathy. Can be left in place for 24 hours w/ an open abdomen/ICU admission

      7. Two-hand, posterior approach to hysterectomy: described by Matsuo 2023. 

      8. Aortic compression/clamping including Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA): heroic measure for life threatening hemorrhage. Clamp below the renal artery.

        1. Risks include arterial injury, thrombosis, risk of mesenteric ischemia, risk of lower limb ischemia

      9. Management of uterine cornua: use a laparotomy sponge to pull on the fundus instead of clamps to avoid shearing of uterine vessels

        1. If vessel damage occurs near fundus/cornua, consider use of a fibrin-containing sealant patch

      10. Resuscitation

        1. Avoid hypothermia, acidosis, hypocalcemia

        2. Transuse 1:1:1 (or 2:1:1) ratio of PRBCs, FFP, platelets 

        3. TXA: 1g bolus, repeated at 30 minutes, repeated again at 24 hours

        4. Hypofibrinogenemia is the strongest biomarker predictive of severe postpartum hemorrhage (cutoff <200)

        5. Redose antibiotics if EBL is >1500cc

    7. Conservative management of PAS (alternatives to cesarean hysterectomy)

      1. Growing support and research for alternative strategies

      2. Uterine preservation: removal of placenta and resection of adherent placental sections without removing the uterus

      3. Expectant management: leaving placenta in situ (partially or totally)

      4. Risks of conservative management: delayed maternal hemorrhage, need for reoperation and subsequent hysterectomy, coagulopathy related to retained POC

      5. Updated literature on conservative management suggests potential safety:

        1. Hessami 2025: systematic review/meta analysis. Total of 2300 patients with PAS, half managed conservatively

          1. C-hyst had higher EBL than both expectant management and uterine preservation, higher need for transfusion than focal resection, higher rates of GU injury

            1. Similar rates of GI injury and thromboembolic events with c-hyst and conservative management

          2. Did not discuss reoperation rates

        2. Matsuzaki 2025: local resection vs. c-hyst

          1. Similar results to above

          2. Rate of hysterectomy after intended local resection was 15%

          3. Compared to prior meta-analyses which have had varying rates of subsequent hysterectomy after expectant management of PAS (ranging from 0-86%)


References

1.    Hessami K, Kamepalli S, Lombaard HA, Shamshirsaz AA, Belfort MA, Munoz JL. Conservative management of placenta accreta spectrum is associated with improved surgical outcomes compared to cesarean hysterectomy: a systematic review and meta-analysis. Am J Obstet Gynecol.Elsevier Inc. 2025;232(5):432-452.e3. doi:10.1016/j.ajog.2025.01.030

2.    Gilner JB, Deshmukh U. Evidence-Based Perioperative Management of Placenta Accreta Spectrum Disorder. Obstetrics and Gynecology. 2025;145(6):595-610. doi:10.1097/AOG.0000000000005920

3.    Levels of Maternal Care: Obstetric Care Consensus No, 9. Obstetrics and Gynecology. 2019;134(2):E41-E55. doi:10.1097/AOG.0000000000003383

4.    Beigi R, Phillips Heine ; R, Silver RM, Wax JR. ACOG Obstetric Care Consensus: Placenta Accreta Spectrum. Obstetrics and Gynecology. 2018;(132):e259-e275.

5.    Wu S, Kocherginsky M, Hibbard JU. Abnormal placentation: Twenty-year analysis. Am J Obstet Gynecol. 2005;192(5 SPEC. ISS.):1458-1461. doi:10.1016/j.ajog.2004.12.074

6.    Eller AG, Bennett MA, Sharshiner M, et al. Maternal morbidity in cases of placenta accreta managed by a multidisciplinary care team compared with standard obstetric care. Obstetrics and Gynecology. 2011;117(2):331-337. doi:10.1097/AOG.0B013E3182051DB2,

7.    Silver RM, Fox KA, Barton JR, et al. Center of excellence for placenta accreta. Am J Obstet Gynecol. 2015;212(5):561-568. doi:10.1016/j.ajog.2014.11.018

8.    Shakur H, Roberts I, Fawole B, et al. Effect of early tranexamic acid administration on mortality, hysterectomy, and other morbidities in women with post-partum haemorrhage (WOMAN): an international, randomised, double-blind, placebo-controlled trial. The Lancet. 2017;389(10084):2105-2116. doi:10.1016/S0140-6736(17)30638-4

9.    Matsuzaki S, Einerson BD, Sentilhes L, et al. Local Resection After Cesarean Delivery for Placenta Accreta Spectrum Disorder: A Systematic Review and Meta-analysis. Obstetrics and Gynecology.Lippincott Williams and Wilkins. 2025;145(6):639-653. doi:10.1097/AOG.0000000000005921

10.  Sentilhes L, Seco A, Azria E, et al. Conservative management or cesarean hysterectomy for placenta accreta spectrum: the PACCRETA prospective study. Am J Obstet Gynecol. 2022;226(6):839.e1-839.e24. doi:10.1016/J.AJOG.2021.12.013

11.  Jauniaux E, Ayres-de-Campos D, Langhoff-Roos J, et al. FIGO classification for the clinical diagnosis of placenta accreta spectrum disorders,. International Journal of Gynecology and Obstetrics. 2019;146(1):20-24. doi:10.1002/IJGO.12761;WGROUP:STRING:PUBLICATION

12.  Scaglione MA, Allshouse AA, Canfield DR, et al. Prophylactic Ureteral Stent Placement and Urinary Injury during Hysterectomy for Placenta Accreta Spectrum. Obstetrics and Gynecology. 2022;140(5):806-811. doi:10.1097/AOG.0000000000004957

13.  Matsuo K, Sangara RN, Matsuzaki S, et al. Placenta previa percreta with surrounding organ involvement: a proposal for management. International Journal of Gynecological Cancer. 2023;33(10):1633-1644. doi:10.1136/IJGC-2023-004615

14.  Matsuzaki S, Mandelbaum RS, Sangara RN, et al. Trends, characteristics, and outcomes of placenta accreta spectrum: a national study in the United States. Am J Obstet Gynecol. 2021;225(5):534.e1-534.e38. doi:10.1016/J.AJOG.2021.04.233

15.  Pala Ş, Atilgan R, Başpınar M, et al. Comparison of results of Bakri balloon tamponade and caesarean hysterectomy in management of placenta accreta and increta: a retrospective study. J Obstet Gynaecol (Lahore). 2018;38(2):194-199. doi:10.1080/01443615.2017.1340440,

16.  Sentilhes L, Ambroselli C, Kayem G, et al. Maternal outcome after conservative treatment of placenta accreta. Obstetrics and Gynecology. 2010;115(3):526-534. doi:10.1097/AOG.0B013E3181D066D4,

17.  Legendre G, Zoulovits FJ, Kinn J, Senthiles L, Fernandez H. Conservative Management of Placenta Accreta: Hysteroscopic Resection of Retained Tissues. J Minim Invasive Gynecol. 2014;21(5):910-913. doi:10.1016/j.jmig.2014.04.004

18.  Lee PS, Kempner S, Miller M, et al. Multidisciplinary approach to manage antenatally suspected placenta percreta: updated algorithm and patient outcomes. Gynecol Oncol Res Pract. 2017;4(1). doi:10.1186/S40661-017-0049-6

19.  Bleich AT, Rahn DD, Wieslander CK, Wai CY, Roshanravan SM, Corton MM. Posterior division of the internal iliac artery: Anatomic variations and clinical applications. Am J Obstet Gynecol. 2007;197(6):658.e1-658.e5. doi:10.1016/j.ajog.2007.08.063

20.  Panaitescu AM, Peltecu G, Botezatu R, Iancu G, Gica N. Risk of Subsequent Hysterectomy after Expectant Management in the Treatment of Placenta Accreta Spectrum Disorders. Medicina (B Aires). 2022;58(5):678. doi:10.3390/MEDICINA58050678

21.  Munoz JL, Blankenship LM, Ramsey PS, McCann GA. Implementation and outcomes of a uterine artery embolization and tranexamic acid protocol for placenta accreta spectrum. Am J Obstet Gynecol. 2023;229(1):61.e1-61.e7. doi:10.1016/j.ajog.2023.03.028

22.  Hecht JL, Baergen R, Ernst LM, et al. Classification and reporting guidelines for the pathology diagnosis of placenta accreta spectrum (PAS) disorders: recommendations from an expert panel. Modern Pathology. 2020;33(12):2382-2396. doi:10.1038/s41379-020-0569-1

23.  National Accreta Foundation. Accessed August 10, 2025. https://www.preventaccreta.org/


Sydney Oesch
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