Placenta Accreta Spectrum (PAS): Diagnosis and Management
| Site: | EHC | Egyptian Health Council |
| Course: | Obstetric and Gynecology Guidelines |
| Book: | Placenta Accreta Spectrum (PAS): Diagnosis and Management |
| Printed by: | Guest user |
| Date: | Wednesday, 6 May 2026, 3:44 AM |
Description
"last update:
14 July 2025" Download Guideline
- Executive Summary
This guideline offers evidence-based recommendations on Placenta Accreta Spectrum. The recommendations are intended to provide healthcare professionals with practical guidance on diagnosis and management of Placenta Accreta Spectrum which can significantly reduce complications and improve the outcome for affected women and their infants.
List of Recommendations
|
Recommendation
|
Strength |
|
What are the risk factors for women with placenta accreta spectrum?
|
|
|
The major risk factors for placenta accreta spectrum are history of accreta in a previous pregnancy, previous caesarean delivery and other uterine surgery, including repeated endometrial curettage. This risk rises as the number of prior caesarean sections increases. |
Strong Recommendation |
|
Women requesting elective caesarean delivery for non-medical indications should be informed of the risk of placenta accreta spectrum and its consequences for subsequent pregnancies. |
GPS |
|
How can placenta accreta spectrum be suspected and diagnosed antenatally?
|
|
|
Antenatal diagnosis of placenta accreta spectrum is crucial in planning its management and has been shown to reduce maternal morbidity and mortality. |
Strong Recommendation |
|
Ultrasound assessment of placental location should be part of routine obstetric care, particularly in women undergoing cesarean section delivery. |
GPS |
|
Previous caesarean delivery and the presence of an anterior low-lying placenta or placenta praevia should alert the antenatal care team of the higher risk of placenta accreta spectrum. |
Strong Recommendation |
|
Ultrasound screening and diagnosis of placenta accreta spectrum
|
|
|
Ultrasound imaging is highly accurate when performed by a skilled operator with experience in diagnosing placenta accreta spectrum. |
Strong Recommendation |
|
Refer women with any ultrasound features suggestive of placenta accreta spectrum to a specialist unit with imaging expertise. |
Strong Recommendation |
|
Standardised definitions should be used in reporting and consideration given to using a template. |
GPS |
|
Women with a history of previous caesarean section seen to have an anterior low-lying placenta or placenta praevia at the routine fetal anomaly scan should be specifically screened for placenta accreta spectrum. |
Strong Recommendation |
|
Patients with previous one or more CS and diagnosed as CS scar pregnancy at 5-6 weeks of gestation are at high risk of developing placenta accreta. They should be counseled and referred to a tertiary hospital for termination of pregnancy. |
Strong Recommendation |
|
Is there a role for magnetic resonance imaging (MRI) in the diagnosis of placenta accreta spectrum?
|
|
|
Clinicians should be aware that the diagnostic value of MRI and ultrasound imaging in detecting placenta accreta spectrum is similar when performed by experts. |
Strong Recommendation |
|
MRI may be used to complement ultrasound imaging to assess the depth of invasion and lateral extension of myometrial invasion, especially with posterior placentation and/or in women with ultrasound signs suggesting parametrial invasion. |
GPS |
|
Women with a history of previous cesarean delivery or uterine surgery who are found to have an anterior low-lying placenta or placenta previa should be considered at increased risk for placenta accreta spectrum, even if imaging does not confirm the diagnosis. |
GPS |
|
Where should women with placenta accreta spectrum be cared for?
|
|
|
Women diagnosed with placenta accreta spectrum should be cared for by a multidisciplinary team in a specialist centre with expertise in diagnosing and managing invasive placentation. |
GPS |
|
Prevention and treatment of anemia during the antenatal period is recommended for women with placenta praevia, a low-lying placenta or accreta as for any pregnant woman. |
GPS |
|
Delivery for women diagnosed with placenta accreta spectrum should take place in a specialist centre with logistic support for immediate access to blood products, adult intensive care unit and neonatal intensive care unit by a multidisciplinary team with expertise in complex pelvic surgery. |
Strong Recommendation |
|
When should delivery be planned for women with placenta accreta spectrum?
|
|
|
In the absence of risk factors for preterm delivery in women with placenta accreta spectrum, planned delivery at 35+0 to 36+6 weeks of gestation provides the best balance between fetal maturity and the risk of unscheduled delivery. |
GPS |
|
Planning delivery of women with suspected placenta accreta spectrum
|
|
|
Once the diagnosis of placenta accreta spectrum is made, a contingency plan for emergency delivery should be developed in partnership with the woman, including the use of an institutional protocol for the management of maternal hemorrhage. |
GPS |
|
What should be included in the consent form for caesarean section in women with suspected placenta accreta spectrum?
|
|
|
Any woman giving consent for caesarean section should understand the risks associated with caesarean section in general, and the specific risks of placenta accreta spectrum in terms of massive obstetric hemorrhage, increased risk of lower urinary tract damage, the need for blood transfusion and the risk of hysterectomy. |
Strong recommendation |
|
Additional possible interventions in the case of massive hemorrhage should also be discussed, including cell salvage and interventional radiology where available. |
Conditional recommendation |
|
What healthcare professionals should be involved?
|
|
|
The elective delivery of women with placenta accreta spectrum should be managed by a multidisciplinary team, which should include senior anesthetists, obstetricians and gynecologists with appropriate experience in managing the condition and other surgical specialties if indicated. In an emergency, the most senior clinicians available should be involved. |
Strong Recommendation |
|
What anesthetic is most appropriate for delivery?
|
|
|
The choice of anesthetic technique for caesarean section for women with placenta accreta spectrum should be made by the anesthetist conducting the procedure in consultation with the woman prior to surgery. |
GPS |
|
The woman should be informed that the surgical procedure can be performed safely with regional anesthesia but should be advised that it may be necessary to convert to general anesthesia if required and asked to consent to this. |
GPS |
|
What surgical approach should be used for women with placenta accreta spectrum?
|
|
|
Intravenous tranexamic acid should be administered at the commencement of surgery because it reduces intraoperative blood loss. |
Strong recommendation |
|
Caesarean section hysterectomy with the placenta left in situ is preferable to attempting to separate it from the uterine wall. |
Strong recommendation |
|
When the extent of the placenta accreta is limited in depth and surface area, and the entire placental implantation area is accessible and visualised (i.e., completely anterior, fundal or posterior without deep pelvic invasion), uterus preserving surgery may be appropriate, including partial myometrial resection. |
Conditional recommendation |
|
Uterus preserving surgical techniques should only be attempted by surgeons working in teams with appropriate expertise to manage such cases and after appropriate counselling regarding risks and with informed consent. |
Conditional recommendation |
|
There are currently insufficient data to recommend the routine use of ureteric stents in placenta accreta spectrum. The use of stents may have a role when the urinary bladder is invaded by placental tissue. |
GPS |
|
What surgical approach should be used for women with placenta percreta?
|
|
|
There is limited evidence to support uterus preserving surgery in placenta percreta and women should be informed of the high risk of peripartum and secondary complications, including the need for secondary hysterectomy. |
GPS |
|
When is interventional radiology indicated?
|
|
|
Larger studies are necessary to determine the safety and efficacy of interventional radiology before this technique can be advised in the routine management of placenta accreta spectrum. |
Strong recommendation |
|
How are women with undiagnosed or unsuspected placenta accreta spectrum best managed at delivery?
|
|
|
If at the time of an elective repeat caesarean section, where both mother and baby are stable, it is immediately apparent that placenta percreta is present on opening the abdomen, the caesarean section should be delayed until the appropriate staff and resources have been assembled and adequate blood products are available. This may involve closure of the maternal abdomen and urgent transfer to a specialist unit for delivery. |
GPS |
|
In case of unsuspected placenta accreta spectrum diagnosed after the birth of the baby, the placenta should be left in situ and an emergency hysterectomy performed. |
GPS |
- Recommendations
1. Antenatal diagnosis and outcome of women with placenta accreta spectrum
The major risk factors for placenta accreta spectrum are history of accreta in a previous pregnancy, previous caesarean delivery and other uterine surgery, including repeated endometrial curettage. This risk rises as the number of prior caesarean sections increases. (10-23)
Women requesting elective caesarean delivery for non-medical indications should be informed of the risk of placenta accreta spectrum and its consequences for subsequent pregnancies. (24-26)
[GPS]
1.2 How can placenta accreta spectrum be suspected and diagnosed antenatally?
[Strong recommendation, Very Low-quality evidence]
Ultrasound assessment of placental location should be part of routine obstetric care, particularly in women undergoing cesarean section delivery.
[GPS]
Previous caesarean delivery and the presence of an anterior low-lying placenta or placenta praevia should alert the antenatal care team of the higher risk of placenta accreta spectrum. (29 & 31-34)
[Strong recommendation, Very Low-quality evidence]
1.2.1 Ultrasound screening and diagnosis of placenta accreta spectrum
Ultrasound imaging is highly accurate when performed by a skilled operator with experience in diagnosing placenta accreta spectrum.
Rational: In 2016, the European Working Group on Abnormally Invasive Placenta proposed a standardised description of ultrasound signs (see Appendix I) used for the prenatal diagnosis of placenta accreta and the International Abnormally Invasive Placenta Expert Group produced a proforma protocol for the ultrasound assessment. (35&36)
[Strong recommendation, Low quality evidence]
Refer women with any ultrasound features suggestive of placenta accreta spectrum to a specialist unit with imaging expertise.
[Strong recommendation, Moderate quality evidence]
Rational: The overall performance of ultrasound when performed by skilled operators is very good with a sensitivity of 90.72% (95% CI 87.2–93.6), specificity of 96.94% (95% CI 96.3–97.5) and diagnostic OR of 98.59 (95%CI 48.8–199.0). (37)
[Strong recommendation, Very Low-quality evidence]
1.2.2 Is there a role for magnetic resonance imaging (MRI) in the diagnosis of placenta accreta spectrum?
Clinicians should be aware that the diagnostic value of MRI and ultrasound imaging in detecting placenta accreta spectrum is similar when performed by experts. (42-45)
[Strong recommendation, Low quality evidence]
[GPS]
Women with a history of previous cesarean delivery or uterine surgery who are found to have an anterior low-lying placenta or placenta previa should be considered at increased risk for placenta accreta spectrum, even if imaging does not confirm the diagnosis.
[GPS]
1.3 Where should women with placenta accreta spectrum be cared for?
Women diagnosed with placenta accreta spectrum should be cared for by a multidisciplinary team in a specialist centre with expertise in diagnosing and managing invasive placentation.
[GPS]
Rational
Women with accreta placentation should be cared for according to the risks of severe maternal bleeding and premature delivery. Placenta percreta can be associated with major prenatal complications from early in pregnancy, such as uterine rupture150–152 and bladder involvement with associated life-threatening haemorrhage. (27 & 46-49)
Prevention and treatment of anemia during the antenatal period is recommended for women with placenta praevia, a low-lying placenta or accreta as for any pregnant woman.
[GPS]
NICU by a multidisciplinary team with expertise in complex pelvic surgery.
[Strong recommendation, Very Low-quality evidence]
Rational: There is increasing evidence from retrospective cohort studies from the USA that women with placenta accreta spectrum diagnosed prenatally, cared for by a specialist multidisciplinary team, are less likely to require large volume blood transfusion and reoperation within 7 days of delivery for bleeding complications compared with women cared for by non-multidisciplinary standard obstetric care without a specific protocol.
In addition, maternal outcomes are improved over time with increasing experience within a well-established multidisciplinary team performing two to three cases per month.22 (27,28,50-54)
1.4 When should delivery be planned for women with placenta accreta spectrum?
In the absence of risk factors for preterm delivery in women with placenta accreta spectrum, planned delivery at 35+0 to 36+6 weeks of gestation provides the best balance between fetal maturity and the risk of unscheduled delivery.
[GPS]
Rational: Clinical factors should be considered when determining the timing of administration of antenatal corticosteroids and the optimal gestational age for delivery in women with placental accreta.
In cases of suspected placenta accreta spectrum, where significant blood loss and caesarean hysterectomy is anticipated, delivery at between 34 and 35 weeks of gestation has been proposed in order to avoid emergency delivery.
In the absence of risk factors for preterm delivery, it is safe to plan the delivery at 36 weeks of gestation. Urgent delivery for bleeding decreases significantly with advancing gestation. Those with no risk factors for preterm birth are at low risk for an unscheduled delivery prior to 36 weeks of gestation. (55-60)
Once the diagnosis of placenta accreta spectrum is made, a contingency plan for emergency delivery should be developed in partnership with the woman, including the use of an institutional protocol for the management of maternal haemorrhage.
[GPS]
Rational: Due to a lack of RCTs or well-controlled observational studies, the optimal management of placenta accreta spectrum remains undefined and is determined by the expertise available, the depth and lateral extension of the accreta portion of the placenta, the presence of an associated placenta praevia, radiological findings, the medical and surgical comorbidities, and finally, the accessibility of a regional team focused on these patients. (61-65)
[Strong recommendation, Very low quality evidence]
Additional possible interventions in the case of massive haemorrhage should also be discussed, including cell salvage and interventional radiology where available. (66)
[Conditional recommendation, low quality evidence]
[Strong recommendation, Very low quality evidence]
Rational: The UK National Patient Safety Agency in collaboration with the RCOG and the Royal College of Midwives set up an expert working group to develop a care bundle for placenta accreta.173 Six elements of good care were agreed upon. The care bundle was then tested in six units over a 5-month pilot study period, and it was found to be both achievable and practical.
The six elements considered to be reflective of good care are(67):
· Consultant obstetrician planning and directly supervising delivery.
· Consultant anaesthetist planning and directly supervising anaesthesia at delivery.
· Blood and blood products available.
· Multidisciplinary involvement in preoperative planning.
· Discussion and consent, including possible interventions (such as hysterectomy, leaving the placenta in situ, cell salvage and interventional radiology).
· Local availability of a level 2 critical care bed.
The choice of anaesthetic technique for caesarean section for women with placenta accreta spectrum should be made by the anaesthetist conducting the procedure in consultation with the woman prior to surgery. (68)
[GPS]
[GPS]
Rational: Both general and regional anaesthetic techniques have been shown to be safe for surgical procedures required for the delivery of placenta accreta spectrum; the judgment of which type of technique to be used should be made on an individual basis. (68)
2.4.1 What surgical approach should be used for women with placenta accreta spectrum?
Intravenous tranexamic acid should be administered at the commencement of surgery because it reduces intraoperative blood loss
[strong, high-quality evidence]
Rational: Tranexamic acid is a widely available hemostatic antifibrinolytic agent that inhibits the enzymatic breakdown of fibrinogen and fibrin by plasmin. Significant international efforts have culminated in several studies investigating tranexamic acid in obstetric trauma and postpartum hemorrhage. Most recently, a large double- blind placebo- controlled trial recruited over 20 000 patients with postpartum hemorrhage to the WOMAN trial. The study demonstrated that, compared with placebo, tranexamic administration significantly reduced death due to massive obstetric hemorrhage without increasing rates of adverse events, including thromboembolism. A recent meta- analysis of nine trials involving 2365 patients confirmed these findings, demonstrating that the administration of tranexamic acid before cesarean delivery significantly reduces intra- and postoperative blood loss and blood transfusion with no increase in thromboembolic events. After this analysis, three more placebo-controlled trials have shown that tranexamic acid administration immediately before cesarean delivery significantly reduces reported intraoperative blood loss and postoperative declines in hemoglobin without any increase in adverse maternal or neonatal effects, No trials have specifically examined the role of tranexamic acid in the surgical management of PAS disorders. However, the quality of the evidence on postpartum hemorrhage justifies its use in the management of women diagnosed prenatally or presenting with PAS disorders at the time of delivery. (69-72)
Caesarean section hysterectomy with the placenta left in situ is preferable to attempting to separate it from the uterine wall.
[ strong, Very low-quality evidence]
Rational: The ACOG recommends planned, preterm caesarean section hysterectomy with the placenta left in situ as removal of a placenta accreta spectrum is associated with significant haemorrhagic morbidity. In cases of high suspicion for accreta during caesarean delivery, the majority of members of the US Society of Maternal-Fetal Medicine (SMFM) and FIGO expert panel proceed with hysterectomy.
A retrospective study of 57 cases of suspected accreta demonstrated significantly reduced short-term morbidity if the placenta is left in place and hysterectomy is performed electively compared with attempting to remove the placenta first. Attempting placental separation risks hysterectomy in up to 100% of cases as also confirmed by other authors. (74-78)
When the extent of the placenta accreta is limited in depth and surface area, and the entire placental implantation area is accessible and visualised (i.e. completely anterior, fundal or posterior without deep pelvic invasion), uterus preserving surgery may be appropriate, including partial myometrial resection.
[conditional, Very low- quality evidence]
Rational: A small cohort study has shown that the introduction of the Triple-P procedure [perioperative placental localisation, pelvic devascularisation and placental non-separation] involving delivery of the fetus via transverse uterine incision above the upper border of the placenta, myometrial excision and reconstruction of the uterine wall reduces the rate of hysterectomy, PPH and duration of hospital stay in women with placenta accreta. The incidence of postoperative complications of the Triple-P procedure depends on comorbidities and in particular, the placental position and the depth of villous invasion. Small case series have also reported on the successful use of compression sutures and on using the cervix as a natural tamponade by inverting it into the uterine cavity and suturing the anterior and/or the posterior cervical lips into the anterior and/or posterior walls of the lower uterine segment.
A systematic review found that uterus preserving surgery resulted in a secondary hysterectomy in 24/77 women (31%), maternal mortality in 2/55 women (4%), subsequent menstruation in 28/34 women (82%) and subsequent pregnancy in 19/26 women (73%). A more recent systematic review showed that uterus preserving surgery is associated with a success rate of 48/76 women (63.2%), a secondary hysterectomy in 23/76 women (30.0%), maternal mortality in 2/54 women (3.7%), subsequent menstruation in 20/37 women (81.1%) and subsequent pregnancy in 21/27 women (77.8%). (79-82)
Uterus preserving surgical techniques should only be attempted by surgeons working in teams with appropriate expertise to manage such cases and after appropriate counselling regarding risks and with informed consent. (79-84)
[conditional, Very low-quality evidence]
There are currently insufficient data to recommend the routine use of ureteric stents in placenta accreta spectrum. The use of stents may have a role when the urinary bladder is invaded by placental tissue.
[GPS]
Rational: There are no RCTs on the use of ureteric stents in placenta accreta spectrum. Ureteric stents or catheters are more commonly used preoperatively in the USA where around 26% of the members of both the SMFM and ACOG fellows are using them in the management of suspected abnormally invasive placenta. (85&86)
2.4.2 What surgical approach should be used for women with placenta percreta?
There is limited evidence to support uterus preserving surgery in placenta percreta and women should be informed of the high risk of peripartum and secondary complications, including the need for secondary hysterectomy.
[GPS]
Rational: There are no well-controlled observational studies, and therefore, no firm recommendations can be made.
The following four approaches have been described.
1. Primary hysterectomy following delivery of the fetus, without attempting placental separation.
2. Delivery of the fetus avoiding the placenta, with repair of the incision leaving the placenta in situ
3. Delivery of the fetus without disturbing the placenta, followed by partial excision of the uterine wall (placental implantation site) and repair of the uterus.
4. Delivery of the fetus without disturbing the placenta, and leaving it in situ, followed by elective secondary hysterectomy 3–7 days following the primary procedure.
2.5 When is interventional radiology indicated?
Larger studies are necessary to determine the safety and efficacy of interventional radiology before this technique can be advised in the routine management of placenta accreta spectrum.
[strong, Very low-quality evidence]
Rational: Studies evaluating the safety and efficacy of interventional radiology in assisting surgical and conservative management of placenta accreta with variable success are very heterogeneous with no data on the diagnosis of the different grades of villous invasion and variable confounding factors, such as placental position and number of previous caesarean deliveries. (91-107)
Women diagnosed with placenta accreta spectrum who decline donor blood transfusion should be cared for in a unit with an interventional radiology service.
[Conditional, Very low quality evidence]
If at the time of an elective repeat caesarean section, where both mother and baby are stable, it is immediately apparent that placenta percreta is present on opening the abdomen, the caesarean section should be delayed until the appropriate staff and resources have been assembled and adequate blood products are available. This may involve closure of the maternal abdomen and urgent transfer to a specialist unit for delivery.
[GPS]
In case of unsuspected placenta accreta spectrum diagnosed after the birth of the baby, the placenta should be left in situ and an emergency hysterectomy performed.
[GPS]
Rational: If the placenta fails to separate with the usual measures, leaving it in place and closing, or leaving it in place, closing the uterus and proceeding to a hysterectomy are both associated with less blood loss than trying to separate it. Attempts at removing placenta accreta at caesarean section can lead to massive haemorrhage, high maternal morbidity and possible maternal death. These risks are particularly high when the caesarean section takes place in an environment with no emergency access to blood bank products and expertise in managing placenta accreta. (18,27,29,34)
- Acknowledgements
We would like to acknowledge the Obstetrics & Gynecology Guidelines Development Committee for adapting this guideline.
Chair of the GDG:
Abdelhamid Mohamed Attia, MD, FRCOG, Prof. of Obstetrics and Gynecology, Faculty of Medicine, Cairo University
Rapporteur of the GDG:
Alaa Eldin Hamed ElFeky, MD, Prof. of Obstetrics and Gynecology, Faculty of Medicine, Ain Shams University
Members of the GDG:
- Aboubakr Mohamed ElNashar, MD, Prof. of Obstetrics and Gynecology, Faculty of Medicine, Banha University
- Ahmed Ezz El-Din Mahran,MD,FRCOG,Prof. of Obstetrics and Gynecology, Faculty of Medicine, Minia University
- Ahmed Fawzy Galal, MD, FRCOG, Prof. of Obstetrics and Gynecology, Faculty of Medicine, Alexandria University
- Ahmed Sekotory Mahmoud, MD, FRCOG, FACOF, Consultant of Obstetrics and Gynecology, Private sector
- Amr Abdel Aziz Nadim, MD, Dean, Faculty of Medicine, 6 October University
- Amr Ahmed AboAlyazid, MD, EFOG, Senior Consultant of Obstetrics and Gynecology, Police Medical Services.
- Amr Essam Abdel Rahman, MD, Senior Consultant of Obstetrics and Gynecology, Ain-Shams University
- Diaa Monier Ajlan, MD, Prof. of Obstetrics and Gynecology, Faculty of Medicine, Tanta University
- Ihab Hassan Abdelfataah, MD, Prof. of Obstetrics and Gynecology, Faculty of Medicine, Galala University
- Magdy Ibrahim Mostafa, MD, Prof. of Obstetrics and Gynecology, Faculty of Medicine, Cairo University
- Mervat Ali Elsersy, MD, Prof. of Obstetrics and Gynecology, Faculty of Medicine, Alexandria University
- Mohamed Mahmoud Fathalla, MD, Prof. of Obstetrics and Gynecology, Faculty of Medicine, Assiut University
- Osama Omar Amer, MD, FRCOG, Major General Dr. of Obstetrics and Gynecology, Armed Forces Hospitals
- Taiseer Maarouf Afifi, MD, Prof. of Obstetrics and Gynecology, Faculty of Medicine for girls, AlAzhar University
- Wafaa Benjamin Basta, FRCOG, Consultant of Obstetrics and Gynecology, Mataria Teaching Hospital, MOHP
We sincerely appreciate the efforts of GDG who initiated the development of this guideline:
- Abdelbaset Fakhry, Prof. of Obstetrics and Gynecology, Faculty of Medicine, Minia University
- Ayman Nady Abdelmeged, Prof. of Obstetrics and Gynecology, Faculty of Medicine, Minia University
- Emad Moussa Ibrahim, Prof. of Obstetrics and Gynecology, Faculty of Medicine, Minia University
- Saad El Gelany, Prof. of Obstetrics and Gynecology, Faculty of Medicine, Minia University
We also extend our gratitude to Dr Mohamed Mourad, Consultant of Obstetrics and Gynecology (FRCOG) and coordinator of the Egyptian Health Council Guideline Working Group, for his unlimited support and guidance.
- Abbreviations
- AICU: Adult Intensive Care Unit
- CS: Caesarean Section
- GDG: Guidelines Development Group
- GPS: Good Practice Statement.
- GRADE: Grading of Recommendations Assessment, Development and Evaluation
- ICU: Intensive Care Unit
- MRI: Magnetic Resonance Imaging
- NICU: Neonatal Intensive Care Unit
- OB/GYN: Obstetrics and Gynecology
- PAS: Placenta Accreta Spectrum
- US: Ultrasound
- Glossary
- Antenatal Diagnosis: The identification of fetal or maternal conditions before birth, typically using imaging modalities such as ultrasound or MRI.
- Caesarean Section Hysterectomy: A surgical procedure involving the removal of the uterus immediately after delivering the baby via caesarean section, commonly performed in severe PAS cases to control life-threatening bleeding.
- Expectant Management: A conservative approach to PAS where the placenta is left in situ (inside the uterus) to allow for natural resorption or later surgical intervention, used in specific clinical scenarios.
- Interventional Radiology: A medical specialty utilizing minimally invasive procedures guided by imaging techniques (e.g., embolization) to manage complications like massive obstetric hemorrhage in PAS.
- Massive Obstetric Haemorrhage: Severe blood loss during pregnancy or childbirth, commonly associated with PAS due to abnormal placental attachment and separation.
- Multidisciplinary Team (MDT): A group of healthcare professionals from various specialties working collaboratively to provide comprehensive care, particularly crucial in managing complex conditions like PAS.
- Placenta Accreta Spectrum (PAS): A range of conditions characterized by abnormal adherence of the placenta to the uterine wall, which includes placenta accreta (superficial attachment), placenta increta (invasion into the uterine muscle), and placenta percreta (penetration through the uterine wall to adjacent organs).
- Placenta Accreta: A condition where the placenta attaches too deeply into the uterine wall without penetrating the muscle, leading to difficulties in placental separation after childbirth.
- Placenta Increta: A more severe form of PAS where the placenta invades the uterine muscle but does not extend beyond it.
- Placenta Percreta: The most severe form of PAS, where the placenta penetrates through the entire uterine wall and can invade nearby organs, such as the bladder.
- Placenta Praevia: A condition where the placenta partially or completely covers the internal opening of the cervix, increasing the risk of severe bleeding during pregnancy and delivery.
- Uterus-Preserving Surgery: A surgical approach aimed at managing PAS while maintaining the integrity of the uterus, often considered for women who desire future fertility.
- Introduction
Placenta Accreta Spectrum (PAS) is a life-threatening obstetric condition characterized by abnormal placental adherence to the uterine wall, leading to significant maternal morbidity and mortality.
The global rise in Cesarean section rates has contributed to an increased incidence of PAS, making it a critical concern in obstetric practice.
In Egypt, the Cesarean delivery rate increased from 52 % in 2014 to 72% in 2021 (1), with a corresponding increase in PAS represents a growing challenge for obstetricians, anesthetists, and multidisciplinary teams involved in peripartum care and placing a substantial burden to the healthcare system.
While precise national statistics on PAS remain limited, hospital-based studies estimate an incidence ranging from 3 - 9 in 1000 births (2,3), significantly higher than the global average of 0.5 - 1 in 1000 births (4)
Classification:
- Placenta accreta: densely adherent placenta due to abnormally deep invasion of the placenta onto the uterine muscle (possibility placenta will separate at birth).
- Placenta increta: adherent placenta embedded into the uterine muscle wall (placenta unlikely to separate at birth).
- Placenta percreta: adherent placenta growing through the uterus and with possible involvement of other organs (placenta unlikely to separate at birth (5)
- Scope and Purpose
This guideline focuses on the spectrum of placenta accreta disorders, collectively referred to as Placenta Accreta Spectrum (PAS), including placenta accreta, increta, and percreta. It does not cover the management of placenta previa not complicated by PAS; for guidance on placenta previa, readers are referred to the guideline titled Placenta Praevia, Diagnosis and Management. The scope encompasses diagnostic criteria, clinical presentation, and relevant management strategies throughout pregnancy, delivery, and the immediate postpartum period.
The purpose of this guideline is to enhance the quality and consistency of care provided to women with PAS through a comprehensive, evidence-based approach. It aims to support early and accurate diagnosis, promote timely and coordinated multidisciplinary management, and reduce the risks of severe maternal morbidity and mortality. By offering actionable clinical recommendations, the guideline strives to improve decision-making, optimize maternal and neonatal outcomes, and ensure the efficient allocation of resources. Ultimately, it seeks to standardize care pathways and facilitate best practices in the management of this high-risk obstetric condition.
- Target Audience
The guideline is intended primarily for obstetricians at tertiary obstetric units who have the experience in dealing with women having PAS, but also, for general obstetricians, general practitioners, anesthetists, radiologists, and other healthcare professionals involved in the care of women with suspected or confirmed PAS. Very often, women with PAS present to primary and secondary care where early identification and referral optimize the outcome. This guideline should be applied to any setting in which PAS would be identified, monitored, or managed.
- Methodology
A comprehensive search for guidelines was done to identify the most relevant ones to consider for adaptation. The inclusion/exclusion criteria that were followed in the search and retrieval of guidelines to be adapted are:
We select guidelines only if they are:
- Evidence-based guidelines
- National and/or international guidelines
- Guidelines published from 2015 to 2025
- Peer reviewed publications
- Guidelines written in English language
We Exclude guidelines that are:
- Written by a single author not on behalf of an organization as guideline to be valid and comprehensive ideally requires multidisciplinary input.
- Published without references as the panel needs to know whether a thorough literature review was conducted and whether the current evidence was used in the preparation of the recommendations.
The following characteristics of the retrieved guidelines were summarized in a table:
- Developing organization/authors
- Date of publication, posting, and release
- Country/language of publication
- Dates of the search used by the source guideline developers
All retrieved Guidelines were screened and appraised using AGREE II instrument (www.agreetrust.org) by at least three members. The panel decided on a cut-off point or ranked the guidelines (any guideline scoring above 50% on the rigor dimension was retained).
Guidelines used in the adaptation process:
2. Jauniaux E, Alfirevic Z, Bhide AG, etal. Royal College of Obstetricians and Gynaecologists. Placenta Praevia and Placenta Accreta: Diagnosis and Management: Green-top Guideline No. 27a. BJOG. 2019 Jan;126(1): e1-e48. (6)
3. American College of Obstetricians and Gynecologists; Society for Maternal-Fetal Medicine. Obstetric Care Consensus No. 7: Placenta Accreta Spectrum. Obstet Gynecol. 2018 Dec;132(6):e259-e275. (7)
4. Hobson SR, Kingdom JC, Murji A, et al. SOGC Clinical Practice Guideline. No. 383-Screening, Diagnosis, and Management of Placenta Accreta Spectrum Disorders. J Obstet Gynaecol Can. 2019 Jul;41(7):1035-1049. (8)
5. Clinical Guideline Placenta Accreta Spectrum (PAS) (C-Obs 20), Women’s Health Committee and associated working groups, RANZCOG Council and Board. (9)
Evidence assessment
According to WHO Handbook for Guidelines, we used the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach to assess the quality of a body of evidence, develop and report recommendations. GRADE methods are used by WHO because these represent internationally agreed standards for making transparent recommendations. Detailed GRADE information is available on the following sites:
- GRADE working group:https://www.gradeworkinggroup.org/
- GRADE online training modules: http://cebgrade.mcmaster.ca/
Table 1: Quality and Significance of the four levels of evidence in GRADE:
|
Quality |
Definition |
Implications |
|
High |
The guideline development group is very confident that the true effect lies close to that of the estimate of the effect |
Further research is very unlikely to change confidence in the estimate of effect |
|
Moderate |
The guideline development group is moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different |
Further research is likely to have an important impact on confidence in the estimate of effect and may change the estimate |
|
Low |
Confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the true effect |
Further research is very likely to have an important impact on confidence in the estimate of effect and is unlikely to change the estimate |
|
Very low |
The group has very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of the effect |
Any estimate of effect is very uncertain |
Table 2; Factors that determine How to upgrade or downgrade the quality of evidence
|
Downgrade in presence of |
Upgrade in presence of |
|
Study limitations - 1 Serious limitations - 2 Very serious limitations |
Dose-response gradient + 1 Evidence of a dose-response gradient |
|
Consistency - 1 Important inconsistency |
Direction of plausible bias + 1 All plausible confounders would have reduced the effect |
|
Directness - 1 Some uncertainty - 2 Major uncertainty |
Magnitude of the effect + 1 Strong, no plausible confounders, consistent and direct evidence + 2 Very strong, no major threats to validity and direct evidence |
|
Precision - 1 Imprecise data |
|
|
Reporting bias - 1 High probability of reporting bias |
|
The strength of recommendations
The strength of a recommendation communicates the importance of adherence to the recommendation.
Strong recommendations: The GDG found that the desirable effects of adherence to the recommendation outweigh the undesirable effects. This means that in most situations the recommendation can be adopted.
Conditional recommendations: This means that the GDG found that there is:
- Greater uncertainty about the strength of evidence, or
- The recommendation may account for a greater variety in patient values and preferences, or
- The resource use makes the intervention suitable for some, but not for other locations.
Conditional recommendations are still the best available evidence to date and it can be adopted if it meets the conditions mentioned with it.
Good Practice Statement: Statements based on the opinion of respected authorities, e.g., the RCOG, ACOG, and the guidelines development group.
- Implementation considerations
Several barriers may hinder the effective implementation and scale-up of the recommendations in this guideline. These factors may be related to the behaviours of patients (or families), the behavior of healthcare professionals, the organization of care, health service delivery or financial arrangements.
Obstacles to effective implementation include:
- Patient engagement
- Collaboration; person centered, team-based collaboration between clinician, dietitian, pharmacist and others involved in care delivery
- Behavior changes: information, guidance and support delivered easily and consistently can help assess sustained behavioral changes.
- Research needs
- Epidemiological studies investigating the prevalence of placenta accreta spectrum (PAS) in Egypt in relation to the rising rate of Caesarean sections.
- RCTs of optimal timing of delivery for placenta accreta are needed.
- RCTs of surgical and nonsurgical management strategies for placenta accreta spectrum (including interventional radiology) and comparing conventional versus conservative management, stratified according to the depth and lateral extension of villous myometrial invasion, are needed.
- Future studies on the diagnosis and management of placenta accreta spectrum should use a standardised evidence-based approach, including systematic correlation between ultrasound signs and detailed clinical diagnosis at delivery, and pathologic confirmation of grades of villous invasiveness where possible.
- Clinical Quality Standards for Monitoring
|
▪️Standardized Ultrasound Definitions and Reporting for Placenta Accreta Spectrum |
|
|
QS.1 |
Ultrasound assessments for suspected placenta accreta spectrum are performed using standardized diagnostic definitions and reported using a uniform, structured template to ensure consistent interpretation, communication, and clinical decision-making.
|
|
QM.1 |
Numerator: Number of ultrasound reports for suspected PAS that use standardized definitions and a uniform structured reporting template. Denominator: Total number of ultrasound assessments performed for suspected PAS. Measure: Evidence that a standardized reporting template and agreed diagnostic definitions for PAS are available and in active use within the imaging service. Target: 100%. |
|
▪️ Documentation of Informed Delivery Planning Discussions |
|
|
QS.2 |
All women with suspected placenta accreta spectrum have a documented delivery plan that includes discussion with the woman and her partner about the risks and indications of blood transfusion and hysterectomy, and addresses any concerns. |
|
QM.2 |
Numerator: Number of women with suspected PAS who have a documented delivery plan that includes discussion of blood transfusion, hysterectomy, and records any expressed concerns. Denominator: Total number of women with suspected PAS. Target: 100%. |
|
▪️ Consultant-Led Obstetric Care |
|
|
QS.3 |
A consultant obstetrician plans and directly supervises the elective birth of women with placenta accreta spectrum.
|
|
QM.3 |
Numerator: Number of women with PAS whose elective birth was planned and directly supervised by a consultant obstetrician. Denominator: Total number of women with PAS undergoing elective birth. Target: 100%. |
|
▪️ Consultant-Led Anaesthetic Care |
|
|
QS.4 |
A consultant anaesthetist plans and directly supervises the anaesthesia for elective delivery in women with placenta accreta spectrum. |
|
QM.4 |
Numerator: Number of women with PAS whose anaesthesia was planned and directly supervised by a consultant anaesthetist during elective delivery. Denominator: Total number of women with PAS undergoing elective delivery. Target: 100%. |
|
▪️ Availability of Blood and Blood Products |
|
|
QS.5 |
Blood and blood products are available on-site before elective surgery in women with placenta accreta spectrum. |
|
QM.5 |
Evidence of availability of cross-matched blood and blood products for women with PAS prior to elective delivery. Target: 100%. |
|
▪️ Comprehensive Informed Consent |
|
|
QS.6 |
Informed consent for elective surgery in women with PAS includes discussion of possible interventions |
|
QM.6 |
Numerator: Number of women with PAS whose documented consent includes discussion of hysterectomy, leaving the placenta in situ, blood transfusion, bladder injury, interventional radiology. Denominator: Total number of women with PAS undergoing elective surgery. Target: 100%. |
- Updating of the guidelines
This guideline will be updated whenever there is new evidence.
- Appendix I
Ultrasound imaging signs commonly used to diagnose placenta accreta spectrum (modified from Collins SL) (108)
|
Ultrasound imaging signs |
Description |
|
2D greyscale signs |
|
|
Loss of the ‘clear zone’ |
Loss or irregularity of the hypoechoic plane in the myometrium underneath the placental bed (the ‘clear zone’). |
|
Abnormal placental lacunae |
Presence of numerous lacunae, including some that are large and irregular (Finberg grade 3), often containing turbulent flow visible in greyscale imaging. |
|
Bladder wall interruption |
Loss or interruption of the bright bladder wall (the hyperechoic band or ‘line’ between the uterine serosa and the bladder lumen). |
|
Myometrial thinning |
Thinning of the myometrium overlying the placenta to less than 1 mm or undetectable. |
|
Placental bulge |
Deviation of the uterine serosa away from the expected plane, caused by an abnormal bulge of placental tissue into a neighboring organ, typically the bladder. The uterine serosa appears intact but the outline shape is distorted. |
|
Focal exophytic mass |
Placental tissue seen breaking through the uterine serosa and extending beyond it. Most often seen inside a filled urinary bladder. |
|
2D colour Doppler signs |
|
|
Uterovesical hypervascularity |
Striking amount of colour Doppler signal seen between the myometrium and the posterior wall of the bladder. This sign probably indicates numerous, closely packed, tortuous vessels in that region (demonstrating multidirectional flow and aliasing artifact). |
|
Subplacental hypervascularity |
Striking amount of colour Doppler signal seen in the placental bed. This sign probably indicates numerous, closely packed, tortuous vessels in that region (demonstrating multidirectional flow and aliasing artifact). |
|
Bridging vessels |
Vessels appearing to extend from the placenta, across the myometrium and beyond the serosa into the bladder or other organs. Often running perpendicular to the myometrium. |
|
Placental lacunae feeder vessels |
Vessels with high velocity blood flow leading from the myometrium into the placental lacunae, causing turbulence upon entry. |
|
3D colour Doppler signs |
|
|
Intraplacental hypervascularity (power Doppler) |
Complex, irregular arrangement of numerous placental vessels, exhibiting tortuous courses and varying calibers. |
- References
(1) Egyptian Central Agency for Public Mobilization and Statistics: EGYPT FAMILY HEALTH SURVEY REPORT 2021.
(2) Saad El Gelany, Mohammed H. Mosbeh, Emad M. Ibrahim et al., Placenta Accreta Spectrum (PAS) disorders: incidence, risk factors and outcomes of different management strategies in a tertiary referral hospital in Minia, Egypt: a prospective study. BMC Pregnancy and Childbirth (2019) 19:313
(3) Salah Roshdy Ahmed, Abdusaeed Aitallah, Hazem M. Abdelghafar, Mohamed Alkhatim Alsammani. Major Placenta Previa: Rate, Maternal and Neonatal Outcomes Experience at a Tertiary Maternity Hospital, Sohag, Egypt: A Prospective Study. Journal of Clinical and Diagnostic Research. 2015 Nov, Vol-9(11): QC17-QC19
(4) Eric Jauniaux , Lene Grønbeck, Catey Bunce , Jens Langhoff-Roos, Sally L Collins. Epidemiology of placenta previa accreta: a systematic review and meta-analysis. BMJ 2019;9:e031193. doi:10.1136/ bmjopen-2019-031193
(5) FIGO Placenta Accreta Diagnosis and Management Expert Consensus Panel. FIGO consensus guidelines on placenta accreta spectrum disorders: series of articles. Int J Gynaecol Obstet. 2018 Mar;140(3):261-298
(6) Jauniaux E, Alfirevic Z, Bhide AG, etal. Royal College of Obstetricians and Gynaecologists. Placenta Praevia and Placenta Accreta: Diagnosis and Management: Green-top Guideline No. 27a. BJOG. 2019 Jan;126(1): e1-e48
(7) American College of Obstetricians and Gynecologists; Society for Maternal-Fetal Medicine. Obstetric Care Consensus No. 7: Placenta Accreta Spectrum. Obstet Gynecol. 2018 Dec;132(6):e259-e275
(8) Hobson SR, Kingdom JC, Murji A, et al. SOGC Clinical Practice Guideline. No. 383-Screening, Diagnosis, and Management of Placenta Accreta Spectrum Disorders. J Obstet Gynaecol Can. 2019 Jul;41(7):1035-1049
(9) Clinical Guideline Placenta Accreta Spectrum (PAS) (C-Obs 20), Women’s Health Committee and associated working groups, RANZCOG Council and Board.
(10) Wu S, Kocherginsky M, Hibbard JU. Abnormal placentation: twenty-year analysis. Am J Obstet Gynecol 2005; 192: 1458–61.
(11) Silver RM, Landon MB, Rouse DJ, Leveno KJ, Spong CY, Thom EA, et al.; National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network. Maternal morbidity associated with multiple repeat cesarean deliveries. Obstet Gynecol 2006; 107: 1226–32.
(12) Fitzpatrick KE, Sellers S, Spark P, Kurinczuk JJ, Brocklehurst P, Knight M. Incidence and risk factors for placenta accreta/increta/percreta in the UK: a national case-control study. PLoS One 2012; 7: e52893.
(13) Soro MP, Denys A, de Rham M, Baud D. Short and long term adverse outcomes after arterial embolisation for the treatment of postpartum haemorrhage: a systematic review. Eur Radiol 2017; 27: 749–62.
(14) Eshkoli T, Weintraub AY, Sergienko R, Sheiner E. Placenta accreta: risk factors, perinatal outcomes, and consequences for subsequent births. Am J Obstet Gynecol 2013; 208: 219.e1–7.
(15) Farquhar CM, Li Z, Lensen S, McLintock C, Pollock W, Peek MJ, et al. Incidence, risk factors and perinatal outcomes for placenta accreta in Australia and New Zealand: a case-control study. BMJ Open 2017; 7: e017713.
(16) Marshall NE, Fu R, Guise JM. Impact of multiple cesarean deliveries on maternal morbidity: a systematic review. Am J Obstet Gynecol 2011; 205: 262.e1–8.
(17) Klar M, Michels KB. Cesarean section and placental disorders in subsequent pregnancies–a meta-analysis. J Perinat Med 2014; 42: 571–83.
(18) Balayla J, Bondarenko HD. Placenta accreta and the risk of adverse maternal and neonatal outcomes. J Perinat Med 2013; 41: 141–9.
(19) Thurn L, Lindqvist PG, Jakobsson M, Colmorn LB, Klungsoyr K, Bjarnadóttir RI, et al. Abnormally invasive placenta-prevalence, risk factors and antenatal suspicion: results from a large population-based pregnancy cohort study in the Nordic countries. BJOG 2016; 123: 1348–55.
(20) Kaser DJ, Melamed A, Bormann CL, Myers DE, Missmer SA, Walsh BW, et al. Cryopreserved embryo transfer is an independent risk factor for placenta accreta. Fertil Steril 2015; 103: 1176–84 e2.
(21) Luke RK, Sharpe JW, Greene RR. Placenta accreta: the adherent or invasive placenta. Am J Obstet Gynecol 1966; 95: 660–8.
(22) H Fox, NJ Sebire, editors. Pathology of the Placenta. 3rd edition. Philadelphia: Saunders-Elsevier; 2007.
(23) Jauniaux E, Jurkovic D. Placenta accreta: pathogenesis of a 20th century iatrogenic uterine disease. Placenta 2012; 33: 244–51.
(24) Ben Nagi J, Ofili-Yebovi D, Marsh M, Jurkovic D. First-trimester cesarean scar pregnancy evolving into placenta previa/accreta at term. J Ultrasound Med 2005; 24: 1569–73.
(25) Jurkovic D, Knez J, Appiah A, Farahani L, Mavrelos D, Ross JA. Surgical treatment of Caesarean scar pregnancy: efficacy and safety of ultrasound-guided suction curettage. Ultrasound Obstet Gynecol 2016; 47: 511–7.
(26) Cali G, Forlani F, Timor-Tritsch IE, Palacios-Jaraquemada J, Minneci G, D'Antonio F. Natural history of Caesarean scar pregnancy on prenatal ultrasound: the crossover sign. Ultrasound Obstet Gynecol 2017; 50: 100–4.
(27) Shamshirsaz AA, Fox KA, Salmanian B, Diaz-Arrastia CR, Lee W, Baker BW, et al. Maternal morbidity in patients with morbidly adherent placenta treated with and without a standardized multidisciplinary approach. Am J Obstet Gynecol 2015; 212: 218.e1-9
(28) Shamshirsaz AA, Fox KA, Erfani H, Clark SL, Salmanian B, Baker BW, et al. Multidisciplinary team learning in the management of the morbidly adherent placenta: outcome improvements over time. Am J Obstet Gynecol 2017; 216: 612.e1–e5.
(29) Silver RM, Fox KA, Barton JR, Abuhamad AZ, Simhan H, Huls CK, et al. Center of excellence for placenta accreta. Am J Obstet Gynecol 2015; 212: 561–8.
(30) Smulian JC, Pascual AL, Hesham H, Qureshey E, Bijoy Thomas M, Depuy AM, et al. Invasive placental disease: the impact of a multi-disciplinary team approach to management. J Matern Fetal Neonatal Med 2017; 30: 1423–7.
(31) Silver RM. Abnormal placentation: Placenta previa, vasa previa and placenta accreta. Obstet Gynecol 2015; 126: 654–68.
(32) Wright JD, Pri-Paz S, Herzog TJ, Shah M, Bonanno C, Lewin SN, et al. Predictors of massive blood loss in women with placenta accreta. Am J Obstet Gynecol 2011; 205: 38.e1–6
(33) Tikkanen M, Paavonen J, Loukovaara M, Stefanovic V. Antenatal diagnosis of placenta accreta leads to reduced blood loss. Acta Obstet Gynecol Scand 2011; 90: 1140–6.
(34) Bowman ZS, Manuck TA, Eller AG, Simons M, Silver RM. Risk factors for unscheduled delivery in patients with placenta accreta. Am J Obstet Gynecol 2014; 210: 241.e1–6.
(35) Collins SL, Ashcroft A, Braun T, Calda P, Langhoff-Ross J, Morel O, et al.; European Working Group on Abnormally Invasive Placenta (EW-AIP). Proposal for standardized ultrasound descriptors of abnormally invasive placenta (AIP). Ultrasound Obstet Gynecol 2016;47:271–5.
(36) Alfirevic Z, Tang AW, Collins SL, Robson SC, Palacios-Jaraquemada J; Ad-hoc International AIP Expert Group. Pro forma for ultrasound reporting in suspected abnormally invasive placenta (AIP): an international consensus. Ultrasound Obstet Gynecol 2016;47: 276–8.
(37) D’Antonio F, Iacovella C, Bhide A. Prenatal identification of invasive placentation using ultrasound: systematic review and meta-analysis. Ultrasound Obstet Gynecol 2013; 42: 509–17.
(38) Jauniaux E, Collins SL, Jurkovic D, Burton GJ. Accreta placentation: a systematic review of prenatal ultrasound imaging and grading of villous invasiveness. Am J Obstet Gynecol 2016;215:712–21. 17.
(39) Jauniaux E, Collins S, Burton GJ. Placenta accreta spectrum: pathophysiology and evidence-based anatomy for prenatal ultrasound imaging. Am J Obstet Gynecol 2018;218:75–87.
(40) Calı G, Giambanco L, Puccio G, Forlani F. Morbidly adherent placenta: evaluation of ultrasound diagnostic criteria and differentiation of placenta accreta from percreta. Ultrasound Obstet Gynecol 2013;41:406–12.
(41) Jauniaux E, Bhide A. Prenatal ultrasound diagnosis and outcome of placenta previa accreta after cesarean delivery: a systematic review and meta-analysis. Am J Obstet Gynecol 2017;217:27–36.
(42) Palacios-Jaraquemada JM, Bruno CH, Martín E. MRI in the diagnosis and surgical management of abnormal placentation. Acta Obstet Gynecol Scand 2013; 92: 392–7.
(43) Meng X, Xie L, Song W. Comparing the diagnostic value of ultrasound and magnetic resonance imaging for placenta accreta: a systematic review and meta-analysis. Ultrasound Med Biol 2013; 39: 1958–65.
(44) 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: 8–16.
(45) Millischer AE, Salomon LJ, Porcher R, Brasseur-Daudruy M, Gourdier AL, Hornoy P, et al. Magnetic resonance imaging for abnormally invasive placenta: the added value of intravenous gadolinium injection. BJOG 2017; 124: 88–95.
(46) Hornemann A, Bohlmann MK, Diedrich K, Kavallaris A, Kehl S, Kelling K, et al. Spontaneous uterine rupture at the 21st week of gestation caused by placenta percreta. Arch Gynecol Obstet 2011; 284: 875–8.
(47) Sun JN, Zhang BL, Yu HY, Zhang Q. Spontaneous uterine rupture due to placenta percreta during pregnancy. Am J Emerg Med 2016; 34: 1918.e1-3.
(48) Abbas F, Talati J, Wasti S, Akram S, Ghaffar S, Qureshi R. Placenta percreta with bladder invasion as a cause of life threatening hemorrhage. J Urol 2000; 164: 1270–4.
(49) Brown JV 3rd, Epstein HD, Laflamme LA, Goldstein BH. First-trimester placenta percreta with urinary bladder invasion. Int J Gynaecol Obstet 2016; 132: 102–3
(50) Bowman ZS, Manuck TA, Eller AG, Simons M, Silver RM. Risk factors for unscheduled delivery in patients with placenta accreta. Am J Obstet Gynecol 2014; 210: 241.e1–6.
(51) Silver RM, Fox KA, Barton JR, Abuhamad AZ, Simhan H, Huls CK, et al. Center of excellence for placenta accreta. Am J Obstet Gynecol 2015;212:561–8.
(52) Smulian JC, Pascual AL, Hesham H, Qureshey E, Bijoy Thomas M, Depuy AM, et al. Invasive placental disease: the impact of a multi-disciplinary team approach to management. J Matern Fetal Neonatal Med 2017; 30: 1423–7.
(53) Eller AG, Bennett MA, Sharshiner M, Masheter C, Soisson AP, Dodson M, et al. Maternal morbidity in cases of placenta accreta managed by a multidisciplinary care team compared with standard obstetric care. Obstet Gynecol 2011; 117: 331–7.
(54) Al-Khan A, Gupta V, Illsley NP, Mannion C, Koenig C, Bogomol A, et al. Maternal and fetal outcomes in placenta accreta after institution of team-managed care. Reprod Sci 2014; 21: 761–71.
(55) Publications Committee, Society for Maternal-Fetal Medicine, Belfort MA. Placenta accreta. Am J Obstet Gynecol 2010; 203: 430–9.
(56) Committee on Obstetric Practice. Committee opinion no. 529: placenta accreta. Obstet Gynecol 2012; 120: 207–11.
(57) Belfort MA. Indicated preterm birth for placenta accreta. Semin Perinatol 2011; 35: 252–6.
(58) Seet EL, Kay HH, Wu S, Terplan M. Placenta accreta: depth of invasion and neonatal outcomes. J Matern Fetal Neonatal Med 2012; 25: 2042–5.
(59) Rac MW, Wells CE, Twickler DM, Moschos E, McIntire DD, Dashe JS. Placenta accreta and vaginal bleeding according to gestational age at delivery. Obstet Gynecol 2015; 125: 808–13.
(60) Perlman NC, Little SE, Thomas A, Cantonwine DE, Carusi DA. Patient selection for later delivery timing with suspected previa-accreta. Acta Obstet Gynecol Scand 2017; 96: 1021–8.
(61) Mavrides E, Allard S, Chandraharan E, Collins P, Green L, Hunt BJ, et al. on behalf of the Royal College of Obstetricians and Gynaecologists. Prevention and management of postpartum haemorrhage. BJOG 2016; 124: e106–49.
(62) Royal College of Obstetricians and Gynaecologists. Blood Transfusions in Obstetrics. Green-top Guideline No. 47. London: RCOG; 2015.
(63) Green L, Knight M, Seeney FM, Hopkinson C, Collins PW, Collis RE, et al. The epidemiology and outcomes of women with postpartum haemorrhage requiring massive transfusion with eight or more units of red cells: a national cross-sectional study. BJOG 2016; 123: 2164–70.
(64)) Brookfield KF, Goodnough LT, Lyell DJ, Butwick AJ. Perioperative and transfusion outcomes in women undergoing cesarean hysterectomy for abnormal placentation. Transfusion 2014; 54: 1530–6.
(65) Balayla J, Bondarenko HD. Placenta accreta and the risk of adverse maternal and neonatal outcomes. J Perinat Med 2013; 41: 141–9.
(66) Royal College of Obstetricians and Gynaecologists. Caesarean Section. Consent Advice No. 7. London: RCOG; 2009.
(67) Paterson-Brown S, Singh C. Developing a care bundle for the management of suspected placenta accreta. The Obstetrician & Gynaecologist 2010; 12: 21–7.
(68) Belfort MA. Indicated preterm birth for placenta accreta. Semin Perinatol 2011; 35: 252–6.
(69) Gynaecol Can. 2016;38:1015–1023. 47. WOMAN Trial Collaborators. Effect of early tranexamic acid admin istration on mortality, hysterectomy, and other morbidities in women with post- partum haemorrhage (WOMAN): An international, ran domised, double- blind, placebo- controlled trial. Lancet. 2017;389: 2105–2116. 48.
(70) Simonazzi G, Bisulli M, Saccone G, Moro E, Marshall A, Berghella V. Tranexamic acid for preventing postpartum blood loss after cesarean delivery: A systematic review and meta- analysis of randomized con trolled trials. Acta Obstet Gynecol Scand. 2016;95:28–37. 49.
(71) Lakshmi SD, Abraham R. Role of prophylactic tranexamic acid in reducing blood loss during elective caesarean section: A randomized controlled study. J Clin Diagn Res. 2016;10:17–21. 50.
(72) Ray I, Bhattacharya R, Chakraborty S, Bagchi C, Mukhopadhyay S. Role of Intravenous tranexamic acid on caesarean blood loss: A Prospective randomised study. J Obstet Gynaecol India. 2017;66:347–352. 51.
(73) Maged AM, Helal OM, Elsherbin MM, et al. A randomized placebo- controlled trial of preoperative tranexamic acid among women under going elective cesarean delivery. Int J Gynecol Obstet. 2015;131: 265–268.
(74) Mehrabadi A, Hutcheon JA, Liu S, Bartholomew S, Kramer MS, Liston RM, et al.; Maternal Health Study Group of Canadian Perinatal Surveillance System (Public Health Agency of Canada). Contribution of placenta accreta to the incidence of postpartum hemorrhage and severe postpartum hemorrhage. Obstet Gynecol 2015; 125: 814–21.
(75) Cal M, Ayres-de-Campos D, Jauniaux E. International survey of practices used in the diagnosis and management of placenta accreta spectrum disorders. Int J Gynaecol Obstet 2018; 140: 307–11.
(76) Committee on Obstetric Practice. Committee opinion no. 529: placenta accreta. Obstet Gynecol 2012; 120: 207–11.
(77) Eller AG, Porter TF, Soisson P, Silver RM. Optimal management strategies for placenta accreta. BJOG 2009; 116: 648–54.
(78) Hudon L, Belfort MA, Broome DR. Diagnosis and management of placenta percreta: a review. Obstet Gynecol Surv 1998; 53: 509–17.
(79) El Tahan M, Carrillo AP, Moore J, Chandraharan E. Predictors of postoperative hospitalisation in women who underwent the Triple-P Procedure for abnormal invasion of the placenta. J Obstet Gynaecol 2018; 38: 71–3.
(80) Shazly SA, Badee AY, Ali MK. The use of multiple 8 compression suturing as a novel procedure to preserve fertility in patients with placenta accreta: case series. Aust N Z J Obstet Gynaecol 2012; 52: 395–9.
(81) El Gelany SA, Abdelraheim AR, Mohammed MM, Gad El-Rab MT, Yousef AM, Ibrahim EM, et al. The cervix as a natural tamponade in postpartum hemorrhage caused by placenta previa and placenta previa accreta: a prospective study. BMC Pregnancy Childbirth 2015; 15: 295.
(82) Teixidor Viñas M, Belli AM, Arulkumaran S, Chandraharan E. Prevention of postpartum hemorrhage and hysterectomy in patients with morbidly adherent placenta: a cohort study comparing outcomes before and after introduction of the Triple-P procedure. Ultrasound Obstet Gynecol 2015; 46: 350–5.
(83) Steins Bisschop CN, Schaap TP, Vogelvang TE, Scholten PC. Invasive placentation and uterus preserving treatment modalities: a systematic review. Arch Gynecol Obstet 2011; 284: 491–502.
(84) Mei J, Wang Y, Zou B, Hou Y, Ma T, Chen M, et al. Systematic review of uterus-preserving treatment modalities for abnormally invasive placenta. J Obstet Gynaecol 2015; 35: 777–82.
(85) Jolley JA, Nageotte MP, Wing DA, Shrivastava VK. Management of placenta accreta: a survey of Maternal-Fetal Medicine practitioners. J Matern Fetal Neonatal Med 2012; 25: 756–60.
(86) Wright JD, Silver RM, Bonanno C, Gaddipati S, Lu YS, Simpson LL, et al. Practice patterns and knowledge of obstetricians and gynecologists regarding placenta accreta. J Matern Fetal Neonatal Med 2013; 26: 1602–9.
(87) Bailit JL, Grobman WA, Rice MM, Reddy UM, Wapner RJ, Varner MW, et al.; Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Maternal-Fetal Medicine Units (MFMU) Network. Morbidly adherent placenta treatments and outcomes. Obstet Gynecol 2015; 125: 683–9.
(88) Publications Committee, Society for Maternal-Fetal Medicine, Belfort MA. Placenta accreta. Am J Obstet Gynecol 2010; 203: 430–9.
(89) Shabana A, Fawzy M, Refaie W. Conservative management of placenta percreta: a stepwise approach. Arch Gynecol Obstet 2015; 291: 993–8.
(90) Clausen C, Lönn L, Langhoff-Roos J. Management of placenta percreta: a review of published cases. Acta Obstet Gynecol Scand 2014; 93: 138–43.
(91) Mei J, Wang Y, Zou B, Hou Y, Ma T, Chen M, et al. Systematic review of uterus-preserving treatment modalities for abnormally invasive placenta. J Obstet Gynaecol 2015;35:777–82.
(92) Teixidor Vi~ nas M, Chandraharan E, Moneta MV, Belli AM. The role of interventional radiology in reducing haemorrhage and hysterectomy following caesarean section for morbidly adherent placenta. Clin Radiol 2014;69:e345–51.
(93) Bouvier A, Sentilhes L, Thouveny F, Bouet PE, Gillard P, Willoteaux S, et al. Planned caesarean in the interventional radiology cath lab to enable immediate uterine artery embolization for the conservative treatment of placenta accreta. Clin Radiol 2012; 67: 1089–94.
(94) Dilauro MD, Dason S, Athreya S. Prophylactic balloon occlusion of internal iliac arteries in women with placenta accreta: literature review and analysis. Clin Radiol 2012; 67: 515–20.
(95) Clausen C, Stensballe J, Albrechtsen CK, Hansen MA, Lönn L, Langhoff-Roos J. Balloon occlusion of the internal iliac arteries in the multidisciplinary management of placenta percreta. Acta Obstet Gynecol Scand 2013; 92: 386–91.
(96) D'Souza DL, Kingdom JC, Amsalem H, Beecroft JR, Windrim RC, Kachura JR. Conservative management of invasive placenta using combined prophylactic internal iliac artery balloon occlusion and immediate postoperative uterine artery embolization. Can Assoc Radiol J 2015; 66: 179–84.
(97))Chou MM, Kung HF, Hwang JI, Chen WC, Tseng JJ. Temporary prophylactic intravascular balloon occlusion of the common iliac arteries before cesarean hysterectomy for controlling operative blood loss in abnormal placentation. Taiwan J Obstet Gynecol 2015; 54: 493–8.
(98) Duan XH, Wang YL, Han XW, Chen ZM, Chu QJ, Wang L, et al. Caesarean section combined with temporary aortic balloon occlusion followed by uterine artery embolisation for the management of placenta accreta. Clin Radiol 2015; 70: 932–7.
(99) Wei X, Zhang J, Chu Q, Du Y, Xing N, Xu X, et al. Prophylactic abdominal aorta balloon occlusion during caesarean section: a retrospective case series. Int J Obstet Anesth 2016; 27: 3–8.
(100) Wu Q, Liu Z, Zhao X, Liu C, Wang Y, Chu Q, et al. Outcome of Pregnancies After Balloon Occlusion of the Infrarenal Abdominal Aorta During Caesarean in 230 Patients With Placenta Praevia Accreta. Cardiovasc Intervent Radiol 2016; 39: 1573–9.
(101) Xie L, Wang Y, Luo FY, Man YC, Zhao XL. Prophylactic use of an infrarenal abdominal aorta balloon catheter in pregnancies complicated by placenta accreta. J Obstet Gynaecol 2017; 37: 557–61.
(102) Wang YL, Duan XH, Han XW, Wang L, Zhao XL, Chen ZM, et al. Comparison of temporary abdominal aortic occlusion with internal iliac artery occlusion for patients with placenta accreta - a non-randomised prospective study. Vasa 2017; 46: 53–7.
(103) Iwata A, Murayama Y, Itakura A, Baba K, Seki H, Takeda S. Limitations of internal iliac artery ligation for the reduction of intraoperative hemorrhage during cesarean hysterectomy in cases of placenta previa accreta. J Obstet Gynaecol Res 2010; 36: 254–9.
(104) Bishop S, Butler K, Monaghan S, Chan K, Murphy G, Edozien L. Multiple complications following the use of prophylactic internal iliac artery balloon catheterisation in a patient with placenta percreta. Int J Obstet Anesth 2011; 20: 70–3.
(105) Gagnon J, Boucher L, Kaufman I, Brown R, Moore A. Iliac artery rupture related to balloon insertion for placenta accreta causing maternal hemorrhage and neonatal compromise. Can J Anaesth 2013; 60: 1212–7.
(106) Teare J, Evans E, Belli A, Wendler R. Sciatic nerve ischaemia after iliac artery occlusion balloon catheter placement for placenta percreta. Int J Obstet Anesth 2014; 23: 178–81.
(107) Matsueda S, Hidaka N, Kondo Y, Fujiwara A, Fukushima K, Kato K. External iliac artery thrombosis after common iliac artery balloon occlusion during cesarean hysterectomy for placenta accreta in cervico-isthmic pregnancy. J Obstet Gynaecol Res 2015; 41: 1826–30.
(108) Collins SL, Ashcroft A, Braun T, Calda P, Langhoff-Ross J, Morel O, et al.; European Working Group on Abnormally Invasive Placenta (EW-AIP). Proposal for standardized ultrasound descriptors of abnormally invasive placenta (AIP). Ultrasound Obstet Gynecol 2016; 47: 271–5.