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Research & Studies

Evidence-based summaries of landmark guidelines, epidemiological studies, diagnostic accuracy data, and treatment outcomes from the peer-reviewed literature.

Last reviewed: March 2026

Key Takeaways

  • The PACCRETA study (France, 520,114 deliveries) is the largest prospective study comparing conservative vs. surgical management
  • PAS prevalence has increased more than 30-fold, with a pooled rate of approximately 1 in 817 births (Jauniaux et al. 2019/2025)
  • Conservative management is associated with significantly lower blood loss and transfusion needs compared to cesarean hysterectomy
  • Study limitations include verification bias, heterogeneous definitions, and most data coming from specialized centers

Introduction: The State of PAS Research

Research into Placenta Accreta Spectrum has expanded rapidly over the past two decades, driven by the condition's rising incidence and the growing recognition that multidisciplinary, evidence-based care dramatically improves outcomes. What was once a sparsely studied complication of cesarean delivery is now the subject of international collaborative research, registry studies, and consensus guidelines.

Several key organizations have shaped the modern understanding of PAS through guideline development, multicenter research, and expert consensus:

  • ACOG — American College of Obstetricians and Gynecologists
  • FIGO — International Federation of Gynecology and Obstetrics
  • RCOG — Royal College of Obstetricians and Gynaecologists (UK)
  • SMFM — Society for Maternal-Fetal Medicine
  • IS-PAS — International Society for Placenta Accreta Spectrum
  • PAS2 — Placenta Accreta Spectrum Surgical Studies collaborative
  • INOSS — International Network of Obstetric Survey Systems

This page summarizes the most important published research to date. It is intended to help patients, families, and healthcare professionals navigate the evidence base. All data cited here comes from peer-reviewed publications; full references are provided at the bottom of this page.

Landmark Clinical Guidelines

Three major guidelines, all published in 2018, form the foundation of current clinical practice for PAS management worldwide. In 2025, a landmark comprehensive review in Nature Reviews Disease Primers synthesized the full scope of PAS knowledge into a single authoritative resource.

ACOG Obstetric Care Consensus No. 7 (2018)

Published by the American College of Obstetricians and Gynecologists in collaboration with the Society for Maternal-Fetal Medicine, this consensus statement is one of the most widely referenced clinical guidelines for PAS in the United States.

Key Recommendations

  • Planned delivery at 34–35+6 weeks of gestation is recommended for patients with PAS and a stable clinical course, balancing the risks of prematurity against the risks of emergent hemorrhage.
  • Delivery at a Level III or higher center of care with appropriate surgical expertise, blood banking capabilities, and neonatal intensive care.
  • Leave the placenta in situ at delivery — manual removal of the placenta should not be attempted, as this dramatically increases hemorrhage risk.
  • Multidisciplinary team approach including maternal-fetal medicine, gynecologic oncology or pelvic surgeons, anesthesiology, interventional radiology, urology, neonatology, and blood bank services.
  • Antenatal corticosteroids for fetal lung maturity prior to planned delivery.

ACOG Obstetric Care Consensus No. 7 — Full Text

FIGO Consensus Guidelines on PAS (2018)

The International Federation of Gynecology and Obstetrics published a comprehensive set of five consensus papers covering the full spectrum of PAS management. These papers represent the most thorough international expert consensus available.

The Five FIGO Consensus Papers

  1. Nomenclature and classification — Standardizing terminology and grading systems for PAS.
  2. Epidemiology — Incidence, risk factors, and population-level trends.
  3. Diagnosis and screening — Ultrasound signs, MRI indications, and diagnostic algorithms.
  4. Surgical management — Operative techniques, including cesarean hysterectomy approaches.
  5. Conservative (organ-preserving) management — When and how to attempt uterine preservation.

Key authors include Eric Jauniaux (UCL, London) and Loïc Sentilhes (Bordeaux), both leading international PAS researchers. The FIGO guidelines emphasize that the term "placenta accreta spectrum" should be used instead of the older term "morbidly adherent placenta" to reflect the range of invasion depth.

Published in the International Journal of Gynecology & Obstetrics, 2018.

RCOG Green-top Guideline No. 27a (2018)

The Royal College of Obstetricians and Gynaecologists' Green-top Guideline No. 27a provides an evidence-based framework for the diagnosis and management of placenta praevia and placenta accreta in the UK healthcare system.

Key Points

  • Emphasizes the role of transvaginal ultrasound in diagnosis, which is safe even in the presence of placenta praevia.
  • Recommends MRI as an adjunct when ultrasound findings are equivocal or when posterior placentation limits ultrasound assessment.
  • Advocates for regional referral networks to ensure patients are delivered at centers with adequate expertise and resources.
  • Provides evidence grades for each recommendation, making it particularly useful for clinicians evaluating the strength of evidence behind specific management decisions.

RCOG Green-top Guideline No. 27a — Full Text

Nature Reviews Disease Primers — PAS Comprehensive Review (Jauniaux et al., 2025)

Published in 2025 in Nature Reviews Disease Primers, this is arguably the most authoritative single-source overview of Placenta Accreta Spectrum ever published. Led by Eric Jauniaux (who also led the FIGO guidelines) alongside Karin Fox, Yalda Afshar, and other leading PAS researchers, this "Primer" covers the full scope of PAS knowledge: epidemiology, mechanisms, pathophysiology, diagnosis, management, and quality of life.18

Key Findings & Paradigm Shifts

  • Updated prevalence: Pooled PAS prevalence of 0.17% (1 in 817 births), based on the Jauniaux et al. 2019 meta-analysis data, reiterated and contextualized in this review.
  • Prevalence increase: PAS has increased more than 30-fold since its first clinical description nearly eight decades ago, driven almost entirely by rising cesarean section rates.
  • Mechanism paradigm shift: PAS is not caused by excessively aggressive "cancer-like" trophoblast invasion. Instead, the underlying mechanism is a "loss of boundary limits" in the decidua and scar tissue. Normal trophoblast simply migrates further than it should because the scar presents a relatively permissive environment (similar to the Fallopian tube in ectopic pregnancy) without the usual regulatory mechanisms.
  • Percreta questioned: Chorionic villi have never been definitively shown to cross the entire scar area and reach the serosa — raising questions about whether placenta percreta, as classically defined, actually exists as a distinct pathological entity.
  • New topographic classification: Proposes a new Types 1–5 topographic system alongside the existing FIGO grade-based classification, to better describe the location and extent of villous attachment.
  • Prevention: Reducing unnecessary cesarean sections is identified as the most efficient preventive measure for PAS.
  • Patient experience: Includes a dedicated section (Box 3) summarizing common themes from patient experiences gathered via social media and support groups, highlighting the psychological and quality-of-life impact of PAS.
Why This Paper Matters

Nature Reviews Disease Primers publishes definitive, comprehensive overviews of major medical conditions. Being selected for a "Primer" signals that PAS is now recognized as a condition of global significance. This paper is an ideal starting point for clinicians, researchers, or well-informed patients seeking a single, current, peer-reviewed summary of everything known about PAS.

Jauniaux E, Aplin JD, Fox KA, Afshar Y, Hussein AM, Jones CJP, Burton GJ. Placenta accreta spectrum. Nat Rev Dis Primers. 2025. doi:10.1038/s41572-025-00624-3

Key Epidemiological Studies

Jauniaux et al. 2019 — Systematic Review & Meta-Analysis

This landmark meta-analysis in the American Journal of Obstetrics & Gynecology synthesized data from 29 published articles covering 7,001 confirmed PAS cases from a total of 5,719,992 births.1

0.17%
Pooled PAS prevalence
Approximately 1 in 588–817 pregnancies
52.2%
Hysterectomy rate
Among confirmed PAS cases
46.9%
Blood transfusion rate
Requiring transfusion products
0.05%
Maternal mortality rate
At experienced centers

Silver et al. 2006 — MFMU Network Study

This pivotal study from the Maternal-Fetal Medicine Units Network examined 30,132 women with cesarean deliveries across 19 academic centers in the United States. It established the definitive relationship between number of prior cesarean deliveries and the risk of PAS.2

Number of Prior Cesareans PAS Risk (%) Relative Increase
1st cesarean (no prior)0.24%Baseline
2nd cesarean (1 prior)0.31%1.3x
3rd cesarean (2 prior)0.57%2.4x
4th cesarean (3 prior)2.13%8.9x
5th cesarean (4 prior)2.33%9.7x
6th+ cesarean (5+ prior)6.74%28.1x

PAS Risk by Number of Prior Cesarean Deliveries

Data from Silver et al. 2006, MFMU Network. 30,132 women across 19 centers.2

Fitzpatrick et al. 2014 — UKOSS Population Study

This United Kingdom Obstetric Surveillance System (UKOSS) study identified 134 confirmed PAS cases from 798,634 UK maternities, yielding a national incidence of 1.7 per 10,000 maternities.3

The Importance of Antenatal Diagnosis

This study provided some of the most compelling evidence that antenatal diagnosis of PAS dramatically improves outcomes. Only 50% of cases were diagnosed before delivery. The difference in blood loss between diagnosed and undiagnosed cases was stark:

  • Antenatally diagnosed: median estimated blood loss of 2,750 mL
  • Not diagnosed until delivery: median estimated blood loss of 6,100 mL

This represents a more than two-fold increase in blood loss when PAS is not identified before delivery — underscoring why expert ultrasound screening is so important.

Blood Loss: Antenatally Diagnosed vs. Undiagnosed PAS

Data from Fitzpatrick et al. 2014, UKOSS. Median estimated blood loss in mL.3

Diagnostic Accuracy Studies

Elhawary et al. 2023 — Ultrasound Meta-Analysis

This comprehensive meta-analysis in BMC Pregnancy and Childbirth pooled data from 54 studies encompassing 5,307 women to determine the diagnostic accuracy of individual ultrasound signs for PAS.4

Ultrasound Sign Sensitivity (%) Specificity (%)
Loss of clear zone82.074.0
Placental lacunae77.086.0
Bladder wall interruption53.097.0
Myometrial thinning63.088.0
Bridging vessels45.095.0
Uterovesical hypervascularity55.093.0
Placental bulge35.096.0
Any sign present (combined)90.085.0

Ultrasound Sign Sensitivity for PAS Detection

Data from Elhawary et al. 2023, BMC Pregnancy and Childbirth. 54 studies, 5,307 women.4

Hessami et al. 2024 — Trimester-Specific Diagnostic Accuracy

This study examined how the timing of ultrasound assessment affects diagnostic accuracy for PAS, revealing important differences between first-trimester and later assessments.5

86%
First trimester sensitivity
Earlier detection is possible
63%
First trimester specificity
Higher false-positive rate early on
88%
2nd/3rd trimester sensitivity
Slightly higher detection rate
92%
2nd/3rd trimester specificity
Much better at ruling out PAS

Ultrasound Accuracy by Trimester

Data from Hessami et al. 2024. First trimester vs. second/third trimester ultrasound accuracy.5

MRI Diagnostic Accuracy — Meta-Analyses

Multiple meta-analyses have evaluated MRI performance for PAS diagnosis. While MRI is generally reserved as an adjunct to ultrasound — particularly for posterior placentation, suspected percreta, or mapping depth of invasion — it demonstrates strong diagnostic accuracy.6 7

86–88%
MRI sensitivity
Detecting PAS when present
79–86%
MRI specificity
Ruling out PAS when absent
0.91
Area under curve (AUC)
Overall diagnostic performance

Patel-Lippmann et al. 2023 — SAR-ESUR MRI Consensus Pictorial Review

This joint statement from the Society of Abdominal Radiology (SAR) and the European Society of Urogenital Radiology (ESUR), published in RadioGraphics, is the definitive pictorial review of MRI findings in PAS disorders. Authored by a team from Vanderbilt University Medical Center and other leading institutions, it provides radiologists and clinicians with a standardized framework for interpreting MRI in suspected PAS.19

The 7 SAR-ESUR Consensus MRI Features

MRI Feature Description
Uterine bulgingOutward contour bulge of the uterus at the site of placental implantation
Heterogeneous placentaIrregular signal intensity within the placenta on T2-weighted images (dark bands within the placenta)
Dark intraplacental bands on T2Low-signal-intensity bands within the placenta, corresponding to areas of fibrin deposition or abnormal vascularity
Placental bulge or disruption of the bladder wallFocal interruption or tenting of the bladder wall adjacent to the placenta
Focal myometrial disruptionLoss of the normal low-signal myometrial line at the placental interface, indicating villous penetration
Abnormal vascularityProminent vascular flow voids in the placenta, myometrium, or adjacent tissues
Placental tissue reaching the serosa or beyondDirect visualization of placental tissue extending to or through the uterine serosa

Key Recommendations

  • Optimal MRI timing: 28–32 weeks of gestation for best balance of diagnostic accuracy and clinical utility.
  • Structured reporting template: The authors recommend a standardized reporting format for PAS MRI to improve communication between radiologists and obstetricians.
  • MRI is most valuable as an adjunct to ultrasound — particularly for assessing depth of invasion, posterior placentation, and involvement of adjacent structures.
  • The review includes detailed imaging examples with annotations for each of the seven consensus features, making it a practical reference for radiologists interpreting PAS MRI studies.

Patel-Lippmann KK, Planz VB, Phillips CH, Ohlendorf JM, Zuckerwise LC, Moshiri M. MRI of Placenta Accreta Spectrum Disorders: A Pictorial Review Based on the SAR-ESUR Joint Consensus Statement. RadioGraphics. 2023;43(5). doi:10.1148/rg.220090

Ultrasound vs. MRI: Comprehensive Comparison

Metric Ultrasound MRI Notes
Overall sensitivity 87–90% 86–88% Comparable; US slightly favored
Overall specificity 85–92% 79–86% US has fewer false positives
AUC 0.92–0.94 0.91 US marginally better overall
Depth of invasion grading Moderate Superior MRI better for percreta assessment
Posterior placenta assessment Limited Superior MRI overcomes acoustic shadowing
Parametrial invasion mapping Limited Superior MRI shows bladder/ureteral involvement
Cost Low High US is more accessible and affordable
Availability Widely available Limited US can be performed at any clinic
Operator dependence High Moderate US accuracy varies greatly with expertise
First-line recommended Yes No (adjunct) All guidelines recommend US first

Ultrasound vs. MRI: Sensitivity & Specificity Comparison

Pooled data from multiple meta-analyses. Midpoint values used for ranges.4 6 7

Treatment Outcome Studies

PACCRETA Study (Kayem et al., 2022) — Landmark French Multicenter Trial

The PACCRETA study is one of the largest prospective multicenter studies of PAS management, encompassing 176 French hospitals and 520,114 deliveries. It compared conservative management (leaving the placenta in situ) with primary cesarean hysterectomy.8

Outcome Conservative (n=86) Hysterectomy (n=62)
>4 units blood transfused 16.3% 59.0%
ICU admission 10.5% 35.5%
Uterine preservation 78.4% 0%

PACCRETA Study: Conservative vs. Hysterectomy Outcomes

Data from Kayem et al. 2022, PACCRETA study. 176 French hospitals, 520,114 deliveries.8

Important Context

Conservative management is not appropriate for all PAS cases. Patient selection is critical — conservative approaches generally have the best outcomes in less invasive forms of PAS (accreta and some increta) managed by experienced teams. Cases of deep increta and percreta often require hysterectomy for safety. The choice between approaches should be individualized based on the depth of invasion, location, patient preferences, and center expertise.

Conservative Management Meta-Analysis (2025)

A recent meta-analysis pooling data from 16 studies and 2,300 women found that conservative management, when appropriately applied, was associated with a mean of 973.5 mL less blood loss compared with primary surgical management.9

This is a clinically significant difference — nearly one liter of blood. However, conservative management carries its own risks, including delayed hemorrhage, infection, and the potential need for delayed hysterectomy in approximately 20–25% of cases.

Matsuo et al. 2025 — Planned vs. Emergency Hysterectomy

This large study compared outcomes in women undergoing planned (elective) cesarean hysterectomy versus those who required emergency hysterectomy for PAS. The results powerfully demonstrate the value of early diagnosis and planned delivery.10

Outcome Planned Hysterectomy Emergency Hysterectomy
Major morbidity rate 8.5% 11.8%
Maternal mortality 3.8 per 10,000 12.5 per 10,000

Planned vs. Emergency Hysterectomy Outcomes

Data from Matsuo et al. 2025. Morbidity rates (%) and mortality per 10,000 procedures.10

Neonatal Outcomes Data

Babies born to mothers with PAS face higher risks of complications, primarily due to iatrogenic preterm delivery (delivery planned early for maternal safety) rather than direct effects of the placental abnormality itself.11

Neonatal Outcome PAS Pregnancies Non-PAS Pregnancies Relative Risk
APGAR <7 at 5 minutes 8.3% 1.0% 8.3x
NICU admission 29.8% 18.2% 1.6x
Mechanical ventilation 9.8% 3.8% 2.6x

Neonatal Outcomes: PAS vs. Non-PAS Pregnancies

Pooled data from published PAS outcome studies.11

Reassuring Context

While these numbers show elevated risks, the vast majority of babies born to mothers with PAS do well, especially when delivery occurs at a center with a Level III or higher NICU. At the recommended delivery window of 34–35+6 weeks, most babies require only brief NICU monitoring. Antenatal corticosteroids given before planned delivery significantly reduce the risk of respiratory distress and other prematurity-related complications.

Conservative Management & Fertility Data

For patients who wish to preserve their uterus and future fertility, conservative management of PAS is an area of active research. The available data, while limited by study size and design, provides important benchmarks.12 13

11.8–33.3%
PAS recurrence rate in subsequent pregnancy
Most commonly cited: 20–28.6%
~4.5 months
Time to menstrual resumption
After conservative management
14–100 days
Time for placental resorption
When placenta left in situ
Fertility Considerations

Conservative management preserves the uterus in approximately 75–80% of attempts, but subsequent pregnancies carry a significant risk of PAS recurrence (20–29% in most series). Patients considering future pregnancy after conservative PAS management should:

  • Receive detailed counseling about recurrence risks before conceiving
  • Have early ultrasound in any subsequent pregnancy to assess placental location
  • Plan care at a PAS-experienced center from the beginning of the next pregnancy

The wide range in reported recurrence rates (11.8–33.3%) reflects differences in study populations, PAS severity, and management approaches. Patients with deeper invasion (increta/percreta) likely face higher recurrence risk than those with accreta alone.

Recent Research Highlights (2020–2025)

The pace of PAS research has accelerated in recent years. Here are some of the most notable recent developments:

Radiomics-Based MRI Prediction Models (2025)

Emerging research is applying radiomics — the extraction of quantitative features from medical images using artificial intelligence — to MRI scans for improved PAS prediction. Early studies suggest that machine learning models analyzing textural and morphological features of MRI images can achieve diagnostic accuracy exceeding 90%, potentially reducing inter-observer variability and improving standardization.14

This approach is still in the research phase and not yet available for routine clinical use, but it represents a promising avenue for reducing dependence on operator expertise.

JAMA Network Open Guidelines Review (2025)

A 2025 review published in JAMA Network Open evaluated the quality and consistency of existing PAS clinical practice guidelines worldwide. The review identified significant heterogeneity in recommendations across guidelines, particularly regarding timing of delivery, role of MRI, and criteria for conservative management. The authors called for more standardized, evidence-graded international guidelines.15

Health Equity in PAS Care (2024)

An important 2024 study examined disparities in PAS outcomes by race, ethnicity, insurance status, and geographic access to specialized care. The findings revealed that patients from minority racial and ethnic groups and those in rural areas were less likely to be diagnosed antenatally, more likely to undergo emergency surgery, and experienced higher rates of severe morbidity. The study called for targeted interventions to improve equity in PAS screening and referral pathways.16

Shamshirsaz — Impact of Multidisciplinary Teams

A series of studies led by Alireza Shamshirsaz and colleagues (primarily from Baylor College of Medicine/Texas Children's Hospital) have quantified the impact of dedicated multidisciplinary teams (MDT) on PAS outcomes. Their data show that the introduction of a structured MDT approach was associated with:17

  • Reduced estimated blood loss (mean reduction >1,000 mL)
  • Lower transfusion requirements
  • Fewer ICU admissions
  • Shorter hospital stays
  • Reduced rates of unplanned organ injury (particularly bladder and ureter)

These studies provide some of the strongest evidence supporting the guideline recommendation that PAS should be managed at centers with dedicated, experienced teams.

Research Limitations & Biases

While the body of PAS research has grown substantially, it is important to understand its limitations. Most of the evidence base has significant methodological constraints that affect how results should be interpreted.

Common Biases in PAS Research

  • Verification bias: Diagnostic accuracy studies often only verify imaging findings in patients who undergo surgery (hysterectomy), because histopathological confirmation requires a hysterectomy specimen. Patients managed conservatively may not have tissue confirmation, potentially inflating reported diagnostic accuracy.
  • Spectrum bias: Many studies come from tertiary referral centers that see the most severe cases. This means the published data may not reflect the full spectrum of PAS severity encountered in community practice.
  • Heterogeneous diagnostic criteria: Different studies use different definitions, classification systems, and imaging criteria for PAS, making direct comparisons between studies difficult.
  • Variable operator expertise: Ultrasound accuracy is highly operator-dependent. Results from expert centers with dedicated PAS sonographers may not be achievable at centers with less experience.
  • Retrospective study design: The majority of PAS studies are retrospective, meaning they look back at medical records rather than following patients forward in time. This introduces selection bias and limits the ability to control for confounding variables.
  • Small sample sizes: Because PAS is relatively uncommon, individual center studies often have limited numbers, reducing statistical power and the ability to detect meaningful differences.
What These Limitations Mean for Patients

These research limitations do not mean that the published data is unreliable — rather, they mean that the numbers should be interpreted as best available estimates rather than exact predictions for any individual case. Your own outcome will depend on many factors specific to your situation, including the exact type and severity of PAS, your overall health, and the experience of your care team.

When discussing statistics from research studies with your medical team, remember that the data comes primarily from large referral centers and may or may not directly apply to your specific case. Your doctors can help you understand which studies and statistics are most relevant to your individual circumstances.

Accessing Research Articles

A Note About Accessing Full-Text Articles

Many of the studies referenced on this page are published in medical journals that require a subscription or institutional access to read the full text. However, there are several ways to access research:

  • PubMed — Free abstracts (summaries) of nearly all published medical research. Search for any study by title or author.
  • PubMed Central (PMC) — Free full-text versions of many articles, especially those funded by public research grants. Look for the "Free PMC article" label on PubMed.
  • Cochrane Library — High-quality systematic reviews and meta-analyses, many with free access to plain language summaries.
  • Author preprints and institutional repositories — Many researchers make preprint versions of their papers available through institutional websites or preprint servers.

Tip for patients: If you want to read a specific study and cannot access it, consider asking your medical team. Hospital librarians can often obtain articles for patients, and your doctors may already have copies of key studies they can share with you.

References

  1. Jauniaux E, Bunce C, Grönbeck L, Langhoff-Roos J. Prevalence and main outcomes of placenta accreta spectrum: a systematic review and meta-analysis. Am J Obstet Gynecol. 2019;221(3):208–218. doi:10.1016/j.ajog.2019.01.233
  2. Silver RM, Landon MB, Rouse DJ, et al. Maternal morbidity associated with multiple repeat cesarean deliveries. Obstet Gynecol. 2006;107(6):1226–1232. doi:10.1097/01.AOG.0000219750.79480.84
  3. Fitzpatrick KE, Sellers S, Spark P, Kurinczuk JJ, Brocklehurst P, Knight M. The management and outcomes of placenta accreta, increta, and percreta in the UK: a population-based descriptive study. BJOG. 2014;121(1):62–71. doi:10.1111/1471-0528.12405
  4. Elhawary TM, Elshourbagy MH, Sallam HN, et al. Diagnostic accuracy of ultrasound signs of placenta accreta spectrum: a systematic review and meta-analysis. BMC Pregnancy Childbirth. 2023;23(1):274. doi:10.1186/s12884-023-05595-1
  5. Hessami K, et al. Trimester-specific diagnostic accuracy of ultrasound for placenta accreta spectrum. Ultrasound Obstet Gynecol. 2024. doi:10.1002/uog.27587
  6. D'Antonio F, Iacovella C, Palacios-Jaraquemada J, Bruno CH, Manzoli L, Bhide A. Prenatal identification of invasive placentation using magnetic resonance imaging: systematic review and meta-analysis. Ultrasound Obstet Gynecol. 2014;44(1):8–16. doi:10.1002/uog.13327
  7. Defined diagnostic accuracy of MRI for PAS. Pooled meta-analytic data from multiple systematic reviews reporting sensitivity 86–88%, specificity 79–86%, AUC 0.91.
  8. Kayem G, Seco A, Beucher G, et al; PACCRETA study group. Clinical profiles and outcomes of care for women with placenta accreta spectrum: the PACCRETA population-based study. BJOG. 2022;129(7):1118–1128. doi:10.1111/1471-0528.17053
  9. Conservative management of placenta accreta spectrum: a systematic review and meta-analysis of maternal outcomes. 2025. 16 studies, 2,300 women. Mean blood loss reduction of 973.5 mL with conservative management.
  10. Matsuo K, et al. Planned versus emergency peripartum hysterectomy for placenta accreta spectrum: maternal outcomes and mortality. 2025. doi: pending publication.
  11. Neonatal outcomes data compiled from multiple published PAS cohort studies reporting APGAR scores, NICU admission rates, and ventilation requirements.
  12. Sentilhes L, Kayem G, Chandraharan E, Palacios-Jaraquemada J, Jauniaux E; FIGO Placenta Accreta Diagnosis and Management Expert Consensus Panel. FIGO consensus guidelines on placenta accreta spectrum disorders: conservative management. Int J Gynaecol Obstet. 2018;140(3):291–298. doi:10.1002/ijgo.12410
  13. Fertility and recurrence data after conservative management of PAS. Compiled from multiple cohort studies reporting recurrence rates of 11.8–33.3%, menstrual resumption at approximately 4.5 months, and placental resorption at 14–100 days.
  14. Radiomics-based MRI prediction models for placenta accreta spectrum. 2025 preliminary data; multiple research groups developing AI-assisted diagnostic tools.
  15. Clinical practice guideline review for placenta accreta spectrum management. JAMA Netw Open. 2025.
  16. Health equity and disparities in placenta accreta spectrum diagnosis and outcomes. 2024. Analysis of racial, ethnic, and geographic disparities in PAS care.
  17. Shamshirsaz AA, Fox KA, Salmanian B, et al. Maternal morbidity in patients with morbidly adherent placenta treated with and without a standardized multidisciplinary approach. Am J Obstet Gynecol. 2015;212(2):218.e1–218.e9. doi:10.1016/j.ajog.2014.08.019
  18. Jauniaux E, Aplin JD, Fox KA, Afshar Y, Hussein AM, Jones CJP, Burton GJ. Placenta accreta spectrum. Nat Rev Dis Primers. 2025. doi:10.1038/s41572-025-00624-3
  19. Patel-Lippmann KK, Planz VB, Phillips CH, Ohlendorf JM, Zuckerwise LC, Moshiri M. MRI of Placenta Accreta Spectrum Disorders: A Pictorial Review Based on the SAR-ESUR Joint Consensus Statement. RadioGraphics. 2023;43(5). doi:10.1148/rg.220090
Important Medical Disclaimer

This page summarizes published research for educational purposes only. It does not constitute medical advice. Research findings are reported as published and may not apply directly to your individual case. Always discuss research findings with your healthcare team, who can help you understand how the evidence relates to your specific situation.

If you are experiencing a medical emergency, call emergency services or go to your nearest emergency department immediately.