Key Takeaways
- 326 confirmed PAS cases from 12 hospitals — the largest published fertility-preserving series worldwide1
- Approximately 80% overall uterine preservation rate, with rates varying by PAS type (Type 1: 81.5%, Type 2: 47.7%, Type 3: 21.8%)
- 202 subsequent pregnancies studied, with 90% reaching term delivery and 0% PAS recurrence2
- Co-led the first and only randomized controlled trial (RCT) comparing conservative surgery to hysterectomy for PAS3
- Dr. Jose M. Palacios-Jaraquemada has 20+ years of experience in fertility-preserving PAS surgery
Program Overview
CEMIC (Centro de Educación Médica e Investigaciones Clínicas) and CYMSA (Centro de Investigaciones en Medicina y Cirugía del Accretismo) in Buenos Aires, Argentina, represent one of the most experienced PAS fertility-preservation programs in the world. Under the leadership of Dr. Jose M. Palacios-Jaraquemada, this program has been performing one-step conservative surgery for PAS for over two decades.
Dr. Palacios-Jaraquemada developed the resective-reconstructive surgical approach (Strategy A), which involves excising the portion of the uterine wall affected by PAS and reconstructing the uterus in a single operation at the time of cesarean delivery. This approach differs fundamentally from the Strategy B (leaving placenta in situ) approach used in France and much of the US — it aims to resolve the PAS immediately rather than waiting for the placenta to resorb.
With data spanning 452 suspected PAS cases (326 histologically confirmed) collected from 12 hospitals, this program has the largest published case series of any fertility-preserving PAS program globally.
Fertility Preservation Status
CEMIC Buenos Aires has the largest published fertility-preserving PAS case series in the world: 326 confirmed cases with approximately 80% overall preservation rate. The program has also published the strongest subsequent pregnancy outcome data of any center: 202 cases studied with 90% term delivery rate and 0% PAS recurrence. This is the only center in the world that has co-led a randomized controlled trial comparing conservative surgery to hysterectomy.12
Strategy A: Resective-Reconstructive Surgery (One-Step Conservative Surgery) — At the time of cesarean delivery, the surgeon excises the segment of the uterine wall where the placenta has invaded abnormally, then reconstructs the uterus. This is a single-operation approach that aims for immediate resolution of the PAS. Success depends heavily on PAS type, location, and the availability of adequate healthy myometrium for reconstruction.1
Preservation Rates by PAS Type
Conservation outcomes vary significantly by PAS severity. The Palacios-Jaraquemada classification and preservation rates:1
| PAS Type | Description | Preservation Rate | Feasibility |
|---|---|---|---|
| Type 1 | Anterior invasion, limited area | 81.5% | Most amenable to conservation |
| Type 2 | Lateral extension, involving parametrium | 47.7% | Feasible with experienced surgeon |
| Type 3 | Extensive invasion, bladder involvement | 21.8% | Difficult; high conversion risk |
| Type 4 | Massive invasion, multiple organ involvement | 0% | Not amenable to conservation |
Subsequent Pregnancy Outcomes: 202-Patient Study
The follow-up study of pregnancies after conservative PAS surgery represents the strongest published fertility outcome data of any center globally:2
The reported 0% PAS recurrence rate in the Palacios-Jaraquemada subsequent pregnancy series is notably lower than the 22–29% recurrence rates reported in the international literature for conservative management overall. This may reflect the resective approach (which removes the affected tissue rather than leaving the placenta to resorb) or differences in patient selection and PAS severity. Further independent replication of this finding would strengthen the evidence. Patients should still be counseled about the possibility of PAS recurrence in subsequent pregnancies.2
Key Physicians
Dr. Jose M. Palacios-Jaraquemada, MD, PhD
Director, CEMIC / CYMSA Placenta Accreta Program, Buenos Aires
Dr. Palacios-Jaraquemada is widely regarded as the pioneer of one-step conservative surgery for PAS. With over two decades of experience and the largest published fertility-preserving case series in the world, he has trained surgeons internationally and contributed foundational knowledge about PAS vascular anatomy and surgical technique. His topographic classification system (Types 1–4) is used to predict conservation feasibility.14
Dr. Albaro José Nieto-Calvache, MD
Fundación Valle del Lili, Cali, Colombia (RCT Collaborator)
Dr. Nieto-Calvache led the first and only randomized controlled trial (RCT) comparing one-step conservative surgery to cesarean hysterectomy for PAS, published in AJOG in 2024. This multicenter trial, co-designed with Dr. Palacios-Jaraquemada, enrolled 60 patients and provided the highest level of evidence currently available for any fertility-preserving PAS approach.3
Published Outcomes
326-Case Surgical Series (BJOG 2020)
The landmark surgical series reported outcomes for 326 histologically confirmed PAS cases from 12 hospitals, using the resective-reconstructive approach:1
- 452 suspected PAS cases, 326 confirmed on histology
- Approximately 80% overall uterine preservation (varies significantly by PAS type)
- Median blood loss: 500 mL for Type 1 cases
- Approximately 20% required conversion to hysterectomy when conservation was initially attempted
First RCT: Conservative Surgery vs. Hysterectomy (AJOG 2024)
The Nieto-Calvache et al. 2024 trial was the first and only randomized controlled trial comparing one-step conservative surgery with cesarean hysterectomy for PAS:3
- 60 patients enrolled (intention-to-treat analysis)
- 85.3% of patients randomized to conservative surgery were able to undergo the planned conservative approach
- In the Type 1 PAS subgroup, conservative surgery showed favorable outcomes compared to hysterectomy
- The trial was stopped early due to difficulty enrolling patients who would accept randomization (patients strongly preferred one approach over the other)
- This remains the only Level I evidence available for any conservative PAS management approach worldwide
202-Pregnancy Follow-Up Study (2022)
The subsequent pregnancy study is the largest published dataset on fertility outcomes after conservative PAS surgery:2
- 202 pregnancies after conservative PAS surgery
- 162 of 179 (90%) delivered at term
- 0% PAS recurrence in the published series
- These outcomes are the strongest published fertility data for any PAS program globally
Practical Information
Location
- Hospital: CEMIC (Centro de Educación Médica e Investigaciones Clínicas), Buenos Aires, Argentina
- Program: CYMSA (Centro de Investigaciones en Medicina y Cirugía del Accretismo)
International Patient Considerations
CEMIC is a private medical institution in Buenos Aires. International patients should consider the following:
- Language: Clinical care is conducted in Spanish. Dr. Palacios-Jaraquemada has published extensively in English-language journals, and communication with international patients can be facilitated, but patients should plan for language support.
- Healthcare System: CEMIC is a private institution. International patients typically pay out-of-pocket, though costs are generally significantly lower than comparable US hospital charges.
- Travel: Buenos Aires is served by Ministro Pistarini International Airport (EZE) with direct flights from major US cities (Miami, New York, Houston, Dallas). Flight time from the US East Coast is approximately 10–11 hours.
- Stay Duration: Patients should plan for several weeks in Buenos Aires, including pre-operative evaluation, surgery, and post-operative recovery.
- Referral Process: Contact the program directly for consultation and surgical planning.
Clinical Trials
Dr. Palacios-Jaraquemada co-led the first RCT for PAS conservative surgery (NCT05013749). As of 2026, no additional trials are listed, but the program actively collaborates with international research networks and has trained surgeons from multiple countries in the resective-reconstructive technique.
References
- Palacios-Jaraquemada JM. One-step conservative surgery for abnormal invasive placenta (placenta accreta, increta, and percreta): resective-reconstructive approach in a series of 326 confirmed cases. BJOG. 2020;127(2):143-151. PMID: 31984808
- Palacios-Jaraquemada JM, et al. Subsequent pregnancy outcomes after one-step conservative surgery for placenta accreta spectrum: a multicenter study. J Maternal-Fetal Neonatal Med. 2022. PMID: 33843411
- Nieto-Calvache AJ, Palacios-Jaraquemada JM, et al. Randomized controlled trial of one-step conservative surgery versus cesarean hysterectomy for placenta accreta spectrum. Am J Obstet Gynecol. 2024. PMID: 38458362
- Palacios-Jaraquemada JM. Topographic classification and surgical planning for placenta accreta spectrum. 2022. PMID: 36372188