Adhesion barriers in gynecologic surgeries and cesarean section: An Asia-Pacific expert panel consensus recommendation.

Shinji Tanigaki, Achla Batra, Te‐Fu Chan, Julian Hean‐Leng Kang, Siu‐Keung Lam, Timothy Yong‐Kuei Lim, Abdul Ghani Nur Azurah, and Graeme Walker discussed the statements and supporting evidence, refined and finalized the statements, participated in voting on the statements, and provided substantial input to the drafting of the manuscript. Raghavendra Mayya organized the meeting and initiated the drafting of consensus statements. All authors critically revised the manuscript for important intellectual content, approved the final version of the article, and are accountable for all aspects of the work.

The expert meetings, manuscript writing, and publication were funded by Baxter Worldwide Medical Affairs, Advanced Surgery, APAC.

Consensus agreement: 95% (Strongly agree—53%; Agree—42%; Disagree—5%); Evidence grade: B. The incidence of adhesions increases with the number of cesarean sections, with rates ranging from 24% to 46% for second cesarean sections, 43% to 75% for third cesarean sections, and 48% to 83% for fourth cesarean sections. 26 , 27 Published data are mirrored by the authors own observations and experiences in the Asia‐Pacific region; they report a 75%–100% incidence of adhesion in Japan, 50%–75% incidence in India, and 10%–25% incidence in Taiwan, Singapore and Hong Kong following abdominopelvic surgery. Adhesions were absent in women who underwent primary cesarean sections; however, at repeat cesarean sections, they were mainly found between the uterus and the bladder, as well as between the uterus and the anterior abdominal wall. 28 Moreover, the occurrence of dense adhesions to the bladder or to the abdominal wall was significantly higher in cases with two or more cesarean sections (46.3% and 48.2%, respectively) than in those with only one cesarean section (29.8% and 25.6%, respectively). 28 The occurrence of dense adhesions was notably higher in cases of multiple (i.e., three or more) cesarean sections than in those with only a second cesarean section (46.1% vs 25.6%, P  < 0.001). 29 Significant complications and sequelae from dense pelvic/uterine adhesions resulting from the previous cesarean section have been observed in some cases of repeat cesarean section. 30 These complications include dense adhesions with no discernible plane between the uterus and the rectus muscle, dense pelvic adhesions involving the omentum to the anterior abdominal wall, fibrous adhesions between the bladder and the lower uterine segment, and adhesions connecting the superior fundus of the uterus to the anterior abdominal wall. 30 However, the impact of adhesions may vary depending on patient factors, surgical technique, and the surgeon's skills. Experienced surgeons may manage adhesions during subsequent surgeries, potentially reducing their impact. More robust evidence is required to substantiate observations that adhesions increase with each cesarean section. Consensus agreement: 91% (Strongly agree—46%; Agree—45%; Disagree—8%; Strongly disagree—1%); Evidence grade: B. Adhesions have been found in a significant proportion of patients who underwent a “second‐look surgery” following initial laparotomy, with reported rates as high as 93%. 31 Although the adoption of laparoscopic surgery has shown promise in reducing the incidence of adhesion‐related readmissions, the overall burden of readmissions related to adhesions remains substantial. 32 In a retrospective study of patients with a history of various abdominopelvic surgeries who subsequently underwent gynecologic laparoscopic procedures for different indications, those with a prior history of open surgery were found to have a higher likelihood of adhesions than patients with a history of laparoscopic surgery (odds ratio: 2.7, 95% CI: 1.4–5.3, P  = 0.0025). 33 Patients who underwent laparoscopic surgery experienced approximately 30% fewer readmissions directly attributed to adhesions than those who underwent open surgery. 32 In the context of colorectal surgery, minimal‐access approaches have been associated with fewer adhesion‐related admissions (6.3% vs 8.2%, P  < 0.001) and reintervention for adhesions (2.8% vs 3.6%, P  < 0.001) than traditional open procedures. 34 It is worth noting that the incidence and impact of adhesions can vary depending on surgical techniques, tissue handling, and the complexity of the cases involved. Consensus agreement: 96% (Strongly agree—37%; Agree—59%; Disagree—4%); Evidence grade: B. The long‐term impact of adhesions on healthcare resources is substantial, as evidenced by a 10‐year follow‐up study involving nearly 30 000 patients. Results revealed that 22.1% of readmissions within the first year were directly or possibly related to adhesions, and this figure increased to 34.6% over the course of 10 years. 3 Notably, not that many readmissions occur for gynecologic cases. Adhesions not only contribute to patient readmissions but also impose significant financial burdens on the healthcare system. The increased rates of hospitalizations, extended inpatient care, and additional hospital and surgical expenditures are direct consequences of adhesion‐related complications. For instance, adhesiolysis procedures alone accounted for 303 836 hospitalizations in the United States in 1994, primarily focusing on the digestive and female reproductive systems. 5 These procedures contributed to a total of 846 415 days of inpatient care and incurred a substantial financial burden of approximately US$1.3 billion in hospitalization and surgeon expenditures .5 . Consensus agreement: 93% (Strongly agree—45%; Agree—48%; Disagree—7%); Evidence grade: B. A study demonstrated the potential benefits of adhesion treatment in improving fertility outcomes. A total of 53 infertile patients, with histories indicating abdominopelvic adhesion formation due to abdominal and/or pelvic surgery, infectious or inflammatory diseases. or trauma, underwent site‐specific manual physical therapy treatments. Among those hoping for natural pregnancy ( n  = 17), 71.4% became pregnant within a year, with 64.3% reporting full‐term deliveries. In the in vitro fertilization group ( n  = 36), clinical pregnancies were documented in 22 out of 33 embryo transfers, yielding an estimated odds ratio for a successful pregnancy of 3.2 (95% CI: 1.55–8.4). 7 Nevertheless, fertility outcomes may vary depending on factors such as the extent and location of adhesion formation, as well as the degree of anatomical distortions caused by the adhesions. Consensus agreement: 97% (Strongly agree—64%; Agree—33%; Disagree—3%); Evidence grade: B. A high percentage of cesarean sections result in adhesions, which delay repeat cesarean delivery of the neonate. 26 , 27 A prospective cohort study revealed a correlation between the number of previous cesarean deliveries and an increase in abdominal adhesions ( P  < 0.001), which made surgical access more difficult. 35 The intervals for surgical procedures were significantly extended for repeat procedures ( P  < 0.001); the time from skin incision to myometrium was longer for repeat cesarean deliveries than for primary ones, with a median of 6 min (range: 1–45 min) versus 3 min (range: < 1–18 min) ( P  < 0.001). Similarly, the time from myometrium to delivery was longer for repeat cesarean deliveries than for primary ones, with a median of 2 min (range: < 1–28 min) versus 1 min (range: < 1–15 min) ( P  < 0.001). The total time from skin incision to delivery for repeat procedures compared to primary ones had a median of 8 min (range: 1–47 min) versus 5 min (range: < 1–26 min) ( P  < 0.001). While adhesions may make entering the abdominopelvic cavity more difficult, they do not routinely prolong operative time or cause an increase in maternal blood loss. Adhesions are not limited to the abdominal wall and can develop around the bowel, bladder, or uterus, increasing the risk of injury to visceral organs. According to a systematic review and meta‐analyses of 196 studies on the incidence of adhesion‐related complications, adhesiolysis during repeat surgery resulted in a 4%–8% ( I 2  = 89%) incidence of iatrogenic bowel injury. 6 With regard to bladder injury, a study of 14 757 cesarean deliveries identified 42 bladder injuries (incidence of 0.28%), where a higher prevalence was observed in women who had prior cesarean section than in those who had not (67.0% vs 32.0%, P  < 0.01). 36 Presence of adhesions was greater in the bladder injury group than in the no‐injury group (60% vs 10%, P  < 0.01). 36 Consensus agreement: 95% (Strongly agree—45%; Agree—50%; Disagree—5%); Evidence grade: B. Chronic pain attributable to adhesions is a common postoperative complication, impacting approximately 20%–40% of patients who have undergone surgery of the female genital or alimentary tract. 6 Data from a meta‐analysis of randomized trials and cohort studies evaluating patients with adhesion‐related chronic postoperative pain of at least 3 months' duration revealed that laparoscopic adhesiolysis alleviated pain in 72% of patients (95% CI: 61.0%–83.0%). 8 Postsurgical adhesions have also been identified as the primary cause of small‐bowel obstruction, frequently observed following an abdominal hysterectomy. A study involving 92 patients revealed that 38% experienced adhesion‐related small‐bowel obstruction after the hysterectomy procedure. 1 Furthermore, in a comprehensive study encompassing 1252 cases of bowel obstructions over a 10‐year period, 31% of obstructions were attributed to adhesions, with 79% of these adhesions being postoperative in nature. 4 However, small bowel obstruction is rarely observed in gynecologic laparoscopic surgery, and its occurrence depends on where the adhesion is formed. Consensus agreement: 97% (Strongly agree—41%; Agree—56%; Disagree—3%); Evidence grade: Not applicable. Results of a survey among Dutch surgeons and surgical trainees revealed that a significant number of respondents underestimated the prevalence and consequences of adhesions, leading to lower knowledge scores. This lack of awareness was associated with increased uncertainty regarding the appropriate use of anti‐adhesive agents, resulting in a substantial proportion of respondents (40.9%) admitting to never informing patients about adhesions, with only 9.8% doing so routinely. 21 However, it is worth noting that not all surgeons employ anti‐adhesive agents. A subsequent follow‐up survey on adhesion awareness revealed that despite the considerable clinical impact of adhesions, adhesion‐related complications were rarely mentioned during the informed consent process. Although 88.1% of respondents acknowledged the clinical relevance of adhesions, the knowledge test scores were concerning, with only 38.8% exhibiting satisfactory awareness. A substantial proportion (32.5%) almost never mentioned adhesions to patients. 37 In the Asia‐Pacific region, there is a similar need for improved awareness, supported by the fact that a high proportion (97%) of experts strongly agreed or agreed to the statement. This is further evidenced by the low rate of adhesion barrier utilization seen among the authors own observations and experiences, as listed in Table  2 . Because postoperative adhesion formation varies between individuals and cannot be predicted prior to surgery, prevention is paramount and presurgical consultations become crucial, for surgeons to thoroughly inform their patients about this potential complication. Common adhesion barriers used in the Asia‐Pacific region. Abbreviations: ADD, sodium hyaluronate/sodium carboxymethylcellulose/alginate; HA, hyaluronic acid; HA‐CMC, hyaluronic acid–carboxymethyl cellulose; ORC, oxidized regenerated cellulose; PDLLA, poly(D,L‐lactic acid); PEG/CMC, polyethylene glycol/carboxymethyl cellulose; PLA, polylactide polymer. Consensus agreement: 100% (Strongly agree—71%; Agree—29%); Evidence grade: B. Meticulous removal of foreign materials, such as blood or excess fluid, within the abdomen is critical for reducing inflammation and preventing adhesions. A study investigating postsurgical adhesion formation in patients requiring hemostasis revealed no evidence of de novo adhesion formation during second‐look surgery performed after 3 months of initial procedures, namely myomectomies, hysterectomies, oviductal reconstruction, and partial resection of the ovary. 57 Meanwhile, the minimally invasive laparoscopic approach offers several potential advantages in decreasing adhesion formation, because it intrinsically meets most of the well‐known principles of atraumatic, gentle, and bloodless surgery. 58 First, its minimal access to the abdominal cavity results in a reduced amplitude of peritoneal injury. 9 , 12 By avoiding incisions through highly vascularized anatomical structures and minimizing tissue trauma, the laparoscopic approach minimizes the risk of postoperative complications. 59 Moreover, this technique prevents the abdominal cavity from being exposed to air and foreign reactive materials, promoting a cleaner and less reactive surgical environment. 2 Second, laparoscopy reduces the manipulation of structures distant from the operative site, leading to decreased mechanical damage of delicate mesothelial cells and a lower risk of local ischemia. 10 , 60 This aspect significantly contributes to diminishing adhesion formation and speeds up the return of peristalsis. 10 , 60 Lastly, the laparoscopic magnified view allows for gentler handling and precise dissection of anatomical structures, ultimately reducing the degree of tissue trauma during the procedure. 10 , 12 This delicate approach not only benefits the operative site but also contributes to overall improved patient outcomes and shorter recovery times. Additionally, the characteristics of suture materials used in the peritoneal cavity, such as ease of manipulation and knotting, can also influence the formation of adhesions. 11 Consensus agreement: 98% (Strongly agree—46%; Agree—52%; Disagree—2%); Evidence grade: Not applicable. Several pharmacologic interventions have shown promise in reducing postoperative peritoneal adhesion formation. Studies have demonstrated that increasing peritoneal fibrinolytic activity using a neurokinin 1 receptor antagonist resulted in a decrease in adhesion formation. 61 Additionally, treatment with intraperitoneal aprotinin and low molecular weight heparin significantly reduced adhesion formation compared to the no‐treatment control group ( P  < 0.05). 17 Another effective inhibitor of adhesion formation is ketorolac tromethamine, a parenterally administered non‐steroidal anti‐inflammatory drug, which limits small bowel adherence to the pelvis after radical pelvic surgery. Median adhesion score for the ketorolac‐treated group was significantly lower than that for the untreated group (0.90 vs 7.03, P  = 0.0001). 18 From our perspective, despite suggestions in the literature, pharmacological agents like anti‐fibrinolytics, steroids, icodextrin, and dextran are not commonly utilized for adhesion prevention in real‐world clinical practice in the Asia‐Pacific region. Consensus agreement: 97% (Strongly agree—35%; Agree—62%; Disagree—3%); Evidence grade: A. Three prospective randomized controlled studies in patients undergoing abdominopelvic surgery confirmed the safety of hyaluronic acid–carboxymethyl cellulose (HA‐CMC; Seprafilm, Baxter International Inc., Deerfield, IL, USA) and oxidized regenerated cellulose (ORC; Interceed, Johnson & Johnson Patient Care Inc., New Brunswick, NJ, USA) adhesion barriers. 14 , 15 , 19 The first study found no statistically significant difference ( P  > 0.05) between the treatment and control groups in the incidences of abscess (4% vs 3%) and pulmonary embolism (<1% in both groups), 14 while the second study found that the incidence of adhesive small bowel obstruction requiring reoperation was significantly lower in the treatment group than in the control group (1.8% vs 3.4%, P  < 0.05). 15 The third study, examining the use of the ORC adhesion barrier during laparoscopy, reported a lower incidence of adverse events (12.0% vs 16.3%, P  = 0.58) and adhesive bowel obstruction (0 vs 2 cases) in the treatment group than in the control group. 19 A liquid‐based adhesion barrier composed of an absorbable gelatin and a carbohydrate polymer (Adcon‐P, Gliatech, Cleveland, OH, USA) proved beneficial in reducing postoperative adhesions and facilitating adhesiolysis. Median adhesion scores of 0 (range: 0–1) was recorded by the treatment group, compared with 2 (range: 0–5, P  < 0.0001) by the control group, based on a six‐point scale that ranged from 0 (no adhesions) to 5 (full‐thickness intestinal injury with adhesiolysis). 20 A modified starch‐based adhesion barrier (4DryField PH [PlantTec Medical GmbH, Lüneburg, Germany]) demonstrated a significant 85% reduction in adhesion extent and severity (mean total adhesion score: 2.2 vs 14.2, P  = 0.004) compared with the control group. 16 The effectiveness of the HA‐CMC barrier is discussed in Statement 11. Caution was advised for cesarean sections with routine use of adhesion barriers, as some anti‐adhesive agents may introduce foreign body–like remnants and lead to increased postoperative febrile morbidity. Additional data is needed to confirm the safety profile of such barriers with regard to infections and long‐term effects on tissue integrity. Consensus agreement: 100% (Strongly agree—36%; Agree—64%); Evidence grade: B. Several clinical trials have demonstrated the safety and efficacy of the HA‐CMC sheet‐based adhesion barrier. Specifically, it has been proven effective in reducing the incidence, severity, and extent of postoperative adhesions following a range of surgical procedures, including abdominal surgery, 14 , 62 , 63 , 64 , 65 myomectomy, 66 colectomy, 67 and repeat cesarean section. 68 , 69 , 70 Moreover, the sheet‐based barrier was found to be safe and effective in minimizing postoperative adhesions to the midline incision. 71 Its use has also decreased the risk and rate of postoperative small bowel obstruction. 63 , 64 In the context of repeat cesarean section, the sheet‐based barrier demonstrated an 85% reduction in adhesion formation. 68 Additionally, its application led to notable improvements in surgical outcomes, as evidenced by reductions in the total duration of surgery (from 7.5 ± 2.8 to 5.4 ± 2.2 min, P  = 0.001), fetal delivery time (from 45.3 ± 10.0 to 39.6 ± 6.5 min, P  = 0.003), and blood loss (from 816.4 ± 352.1 to 630.8 ± 255.9 g, P  = 0.01). 69 Consensus agreement: 95% (Strongly agree—24%; Agree—71%; Disagree—5%); Evidence grade: B. The HA‐CMC sheet‐based adhesion barrier can be applied in laparoscopic surgeries to protect the traumatized surfaces of the uterus, ovaries, and tubes, although its application can be challenging due to its fragility and stickiness caused by moisture. The procedure involves rolling it up in a plastic package and delivering it through the main trocar, where it is then unrolled and positioned over the target area. 72 One method includes cutting the sheet‐based barrier into quarters, moistening and softening each piece on a wet wrung gauze until it naturally curls. Two pieces of the film are then rolled up with the backing paper from the package and delivered into the abdomen through an 11‐mm trocar, ensuring a high success rate without requiring special equipment. 73 Another technique entails cutting the sheet‐based barrier into three equal rectangle‐shaped pieces, allowing them to absorb moisture for a few minutes, and placing them on gauze. The gauze is then folded in half and grasped by forceps, acting as a working station to prevent the sheet‐based barrier from directly attaching to surrounding tissues, making it easier for surgeons to handle. The gauze‐encased sheet‐based barrier is inserted through a 12‐mm trocar and placed close to the target site. After pressing the sheet‐based barrier onto the area, the gauze can be easily removed through the same trocar. 74 Nevertheless, the experts agreed that some surgeons may encounter challenges when applying the sheet‐based barrier, because it requires specific techniques and may not provide the same level of ease of use as other adhesion barriers. Consensus agreement: 91% (Strongly agree—19%; Agree—72%; Disagree—9%); Evidence grade: Not applicable. Studies have shown that starch powder–based hemostats, such as Arista (BD, Franklin Lakes, NJ, USA) and HaemoCer (BioCer, Bayreuth, Germany), are ineffective in preventing adhesions. 75 , 76 Their reduced efficacy can be attributed in part to their short retention time within the body, typically lasting only about 1–3 days. 77 In contrast, the HA‐CMC sheet‐based adhesion barrier can remain at surgical sites for up to a week. 78 To better understand and compare the performance of these products, we believe that it is imperative to conduct head‐to‐head studies specifically comparing the sheet‐based adhesion barrier with powder‐based hemostats. Consensus agreement: 96% (Strongly agree—14%; Agree—82%; Disagree—4%); Evidence grade: A. The use of an ORC adhesion barrier showed promising results in reducing adhesions in various gynecologic pelvic surgeries. In a study of 694 women who underwent intracapsular myomectomy, the rate of adhesions decreased from 28.1% to 22.0% with the application of the ORC adhesion barrier during laparotomy. 79 Similarly, in 55 patients with bilateral ovarian disease, the severity of adhesions (scored from 0 to 3) was slightly reduced from 1.1 to 0.8, and the adhesion area decreased from 2.8 to 1.7 cm 2 after wrapping one ovary with the ORC adhesion barrier. The percentage of ovaries that developed adhesions was significantly reduced from 75% to 53%. 80 Meanwhile, laparoscopic application of the ORC adhesion barrier after endometriosis resection in 20 patients showed a notable reduction in the four‐point adhesion score (0–3) from 1.1 to 0.4 when compared with 20 control patients without the barrier. 81 Consensus agreement: 96% (Strongly agree—46%; Agree—50%; Disagree—4%); Evidence grade: Not applicable. Surgeons should consider the use of adhesion barriers for patients at high risk of forming clinically significant adhesions, such as those with endometriosis or pelvic inflammatory disease or those undergoing myomectomy. 82 Younger patients, who have a higher lifetime risk of recurrent adhesive small bowel obstruction, may also benefit from adhesion barriers for both primary and secondary prevention. 83 While adhesion barriers are recommended for all patients undergoing surgery if financially feasible, we opine that specific patient groups can particularly benefit from their application. These include younger patients seeking to preserve fertility, those with one or more previous scars, patients undergoing bilateral tubal ligation with potential subsequent hysterectomy, and those undergoing a first cesarean section, to prevent adhesion formation. Additionally, patients with extensive adhesions at the start of surgery or found during a second cesarean section, along with those who have specific risk factors like infection, meconium‐stained liquor, and excessive bleeding, could benefit from adhesion barriers. Surgeries with a high risk for adhesion development, such as lower segment cesarean sections, cesarean sections requiring an inverted T or extended J, endometriosis, and myomectomies, also warrant consideration for adhesion barriers. Ultimately, the decision to use adhesion barriers lies with the surgeon based on a thorough assessment of patient history, postoperative notes from previous surgeons to help identify patients at risk for adhesions, and open discussion with patients regarding pregnancy and/or cesarean section history as well as future plans.

The present study presents 15 evidence‐based consensus statements concerning the use of adhesion barriers in gynecologic surgeries and cesarean sections. These recommendations are particularly relevant to Asia‐Pacific healthcare professionals because they are derived from insights provided by gynecologists and obstetricians from within the same region. The main objective is to advocate for effective adhesion management strategies and to raise awareness throughout the wider medical community. The authors emphasize the need for further research and high‐quality randomized controlled trials in the Asia‐Pacific region to validate these recommendations and enhance understanding of adhesion prevention.

Adhesions caused by gynecologic procedures and cesarean sections pose significant clinical, social, and economic challenges due to potential outcomes like pelvic pain, infertility, bowel obstruction, and the need for further surgeries to address adhesion‐related issues. 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 Approximately 35% of patients who undergo open abdominal or pelvic surgery experience an average of 2.1 readmissions within the subsequent 10 years, directly or potentially linked to adhesions. 3 Among these readmissions, 22% occur within the first year following the initial surgery. 3 Adhesion prevention represents a critical unmet need in surgical therapeutics, as surgeons consistently encounter adhesions but struggle to effectively address them due to the complexities involved in their development. In gynecologic surgeries, the main strategies for preventing adhesions involve optimizing surgical techniques 9 , 10 , 11 , 12 , 13 and utilizing adhesion‐prevention agents/barriers 14 , 15 , 16 , 17 , 18 , 19 , 20 ; however, assessing the impact of postoperative adhesion formation in patients poses challenges, 21 , 22 limiting the available evidence for adhesion barriers. The issue of adhesion prevention is further compounded in resource‐limited settings. 22 To bridge the gaps in adhesion prevention knowledge and practices, a set of consensus statements was developed to discuss current clinical practices surrounding the use of adhesion barriers, present the perspective of experts in the Asia‐Pacific region on the necessity of adhesion prevention in gynecologic surgeries and cesarean sections, and more importantly, raise awareness among the broader medical community, with the goal of improving patient outcomes in surgical settings.

Raghavendra Mayya currently works as medical director at Baxter Healthcare (Asia) Pte Ltd. His contributions to this consensus work are purely academic and do not involve any promotional interest. None of the other authors have any direct conflicts of interest related to this article.

Consensus development began with a series of regional advisory board meetings held between June and July 2021. These meetings gathered a diverse group of experts to deliberate on the current clinical practice regarding the use of adhesion barriers, the need for adhesion prevention in gynecologic surgeries and cesarean section, and strategies for adhesion management through awareness improvement. Following the advisory board meetings, an expert panel was established, comprising eight physicians specializing in obstetrics and gynecology. The panelists were selected from various healthcare settings, including public, private, and academic centers, representing seven Asia‐Pacific countries/regions: Australia, Hong Kong, India, Japan, Malaysia, Singapore, and Taiwan. Relevant articles published between 1993 and 2022 were identified on MEDLINE (via PubMed) using the following search terms: “abdominopelvic surgery”, “adhesion barriers”, “adhesion prevention”, “anti‐adhesion”, “cesarean section delivery”, “laparoscopy”, “laparotomy”, “myomectomy”, “oxidized regenerated cellulose”, “postoperative adhesions”, “repeat cesarean section” and “Seprafilm”. Articles from the literature search were included if they defined, described, or recommended clinical information related to adhesion barriers in gynecologic surgeries and cesarean section on the following topics: (1) incidence of postoperative adhesions in Asia; (2) common post–cesarean section adhesion complications; (3) current status in the application of adhesion barriers; (4) pathogenesis and prevention of adhesion formation; (5) evidence of absorbable barriers in adhesion prevention; and (6) recommendations and future considerations for the use of adhesion barriers. Information extracted from full‐text publications was used to develop draft consensus statements. Each statement was assigned the highest level of evidence available, through a systematic review of the literature, and graded based on the average evidence level for each supporting reference, using the Oxford Center for Evidence‐Based Medicine criteria (Table  S1 ). 23 A virtual meeting was held in June 2022 to allow the panelists to review and discuss the 17 draft statements. Individual panelists indicated their respective position for each of the 17 statements in a blinded online voting exercise by selecting one of three options: strongly agree, agree but a major modification is required, or do not agree. The panelists also amended the statements for accuracy and clarity, and disagreements were resolved through open discussion. A set of 15 consensus statements was shortlisted for the subsequent step. The approved set of statements and supporting evidence were then shared via Google Forms with an expanded group of experts across the Asia‐Pacific region for a second round of blinded online voting. Responses were gathered from 109 experts from Taiwan (26), India (26), Malaysia (22), Japan (20), Singapore (12), Australia (2), and Thailand (1). Each expert rated the statements based on a 4‐point Likert scale (strongly agree, agree, disagree, or strongly disagree) and provided the reasons for their reservations or disagreement. A combined “strongly agree” and “agree” acceptance rate of ≥70% was considered a priori to represent consensus for each statement. 24 , 25 Results of voting and feedback on the statements were collated and shared with the panelists for a final review, and appropriate revisions were made to the consensus statements until they were unanimously approved (Figure  1 ). The final set of 15 consensus statements and their respective levels of agreement are summarized in Table  1 . Flow diagram of the modified Delphi process used to generate consensus statements. Summary of consensus statements and agreement levels. The incidence and severity of adhesions increase with each cesarean section. (Evidence grade: B) Adhesions develop routinely after both open and laparoscopic surgeries although laparoscopic surgeries are associated with a lower incidence of adhesion formation compared to open surgeries. (Evidence grade: B) The clinical and economic burden of postoperative adhesions is extensive and have important consequences to patients, surgeons, and the healthcare system. (Evidence grade: B) There is evidence that infertility can also occur secondary to adhesions as a result of prior surgeries irrespective of underlying pathology. (Evidence grade: B) Adhesions can cause difficulty in entering the abdominopelvic cavity at repeat cesarean section, leading to prolonged time in delivering the neonate and a higher risk of bowel and bladder injury. (Evidence grade: B) Adhesions can cause small bowel obstruction and chronic abdominal as well as pelvic pain. (Evidence grade: B) Postoperative adhesion awareness still needs improvement. There is a need to create awareness among surgeons about postoperative adhesions for improved surgical outcomes. (Evidence grade: Not applicable) Meticulous hemostasis and minimally invasive surgical techniques are imperative in reducing adhesion formation. (Evidence grade: B) The use of anti‐adhesion agents may help to minimize the incidence of adhesions in addition to good surgical technique. (Evidence grade: Not applicable) Adhesion barriers have proven to be safe and effective in reducing postoperative adhesions. (Evidence grade: A) The HA‐CMC sheet‐based adhesion barrier is safe and effective in preventing and reducing postoperative adhesion formation. (Evidence grade: B) The HA‐CMC sheet‐based adhesion barrier can be successfully applied in laparoscopic surgeries using modified methods. (Evidence grade: B) The HA‐CMC sheet‐based adhesion barrier was effective in reducing adhesions through prolonged retention at surgical sites compared to powder‐based hemostats. (Evidence grade: Not applicable) The use of an ORC absorbable adhesion barrier is associated with a reduced incidence of pelvic adhesion formation following laparotomy. (Evidence grade: A) The use of adhesion barriers is recommended in patients who are expected to benefit from adhesion barrier use. (Evidence grade: D) Abbreviations: HA‐CMC, hyaluronic acid–carboxymethyl celullose; ORC, oxidized regenerated cellulose. Sum of the percentage of “strongly agree” and “agree”.

Table S1.