Anorectal malformations (ARM) represent a diverse group of congenital anomalies involving the distal rectum, anal canal, and urogenital tract, occurring in approximately 1 in 5000 live births.[1] Among females, vestibular fistula, encompassing both anovestibular and rectovestibular types, is the most frequently encountered variety. Traditional management involved posterior sagittal anorectoplasty (PSARP), introduced by Peña and De Vries (1982),[2] which provided an anatomical correction through a posterior approach but often required a staged procedure with colostomy, leading to multiple hospitalizations and prolonged recovery. Furthermore, the prone position used during PSARP posed anesthetic difficulties, especially in patients with associated cardiac defects. The anterior sagittal anorectoplasty (ASARP), described by Okada et al. (1993)[3] and later popularized by Wakhlu et al. (1996),[4] modified the approach by using a supine anterior midline incision, allowing clear separation of the rectum from the vagina under direct vision and reconstruction of the perineal body. This single-stage, cosmetically favorable, and anatomically precise technique eliminates the need for colostomy, minimizes infection risk, and reduces hospital stay. Despite wide adoption of ASARP, literature from Kerala and South India reporting long-term continence and complication profiles remains scarce. The present study was therefore undertaken to evaluate both functional outcome and postoperative complications following primary ASARP in female children with vestibular fistula.

This follow-up descriptive study was conducted in the Department of Pediatric Surgery, Government Medical College, Thiruvananthapuram, between 2008 and 2017 after obtaining Institutional Ethics Committee approval. Study Population The study included female children with vestibular fistula who underwent primary ASARP during the study period. Children with high-type ARM or those who underwent staged procedures with colostomy were excluded. A total of 34 patients who met the inclusion criteria and were available for follow-up were included in the final analysis. The mean follow-up period was approximately 6 months to 1 year post-surgery. Procedure All surgeries were performed under general anesthesia in the supine lithotomy position. A midline incision was made from the fistulous opening to the proposed anal site. The rectum was carefully mobilized, separated from the vaginal wall under direct vision, and placed within the external sphincter complex. The perineal body was reconstructed, ensuring the neoanus was positioned centrally within the sphincter. Standardized preoperative bowel preparation and antibiotic prophylaxis were used for all cases. Postoperative care included sitz baths, anal dilatations from the third postoperative week, and regular follow-up. Data Collection and Variables Patient details were extracted from medical records and supplemented with outpatient follow-up data. The following parameters were analyzed: • Functional outcome: using the Kelly scoring system[7] (Good = 5–6, Fair = 3–4, Poor = ≤2) • Staining and soiling status • Anal sphincter tone: assessed by per rectal examination (Strong/Weak) • Bowel movement frequency: categorized as o Group A – ≥1/day, no staining/soiling o Group B – ≥1/day, with staining/soiling o Group C – <1/day • Constipation (none/occasional/persistent) • Intraoperative and postoperative complications: including vaginal tear, wound infection, dehiscence, and anal stenosis Statistical Analysis Data were entered in Microsoft Excel and analyzed using SPSS v25.0. Continuous variables were expressed as mean ± standard deviation (SD) and categorical variables as frequency and percentage.

The present analysis was conducted to evaluate the functional outcome and postoperative complications following primary anterior sagittal anorectoplasty (ASARP) in female patients with anorectal malformations (ARM), specifically those presenting with vestibular fistula and its variants. Data from 34 patients were analyzed to assess postoperative continence using the Kelly scoring system, along with additional parameters such as staining, soiling, sphincter strength, bowel movement frequency, and constipation. Postoperative and intraoperative complications, including wound-related issues, anal stenosis, and vaginal tears, were also recorded to determine the safety and efficacy of the procedure. Descriptive statistics were used to summarize continuous variables as mean ± standard deviation (SD), and categorical variables were expressed as frequencies and percentages. The analysis aimed to establish the functional success rate and morbidity profile of single-stage ASARP in the correction of female anorectal malformations. 1. Baseline Characteristics of the Study Population Table 1. Baseline Characteristics of Female Patients Undergoing Primary ASARP (n = 34) Variable Minimum Maximum Mean ± SD / n ( %) Current age (months) 7 99 17.12 ± 15.63 Age at surgery (months) 3 48 12.74 ± 12.05 Post-operative stay (days) 5 11 8.35 ± 1.63 Type of ARM Rectovestibular Fistula RVF 19 (55.9%) Anterior Perineal Anus (APA) 7 (20.6 %) Anovestibular Fistula (AVF) 4 (11.8 %) Ano cutaneous fistula (ACF) 4 (11.8 %) Associated anomalies Present in 11 (32.4 %) patients • Cardiac (ASD / CHD) 5 (14.7 %) • Others (VACTERAL, sacral agenesis, CNS / renal) 6 (17.7 %) The present study included 34 female children who underwent primary anterior sagittal anorectoplasty (ASARP) for anorectal malformation with vestibular fistula and its variants. The mean current age of the study population was 17.12 ± 15.63 months (range 7–99 months), while the mean age at surgery was 12.74 ± 12.05 months, showing that most girls had their definitive repair performed in infancy. The post-operative stay averaged 8.35 ± 1.63 days, indicating early discharge with minimal morbidity. With respect to anatomical subtypes, rectovestibular fistula (RVF) was the predominant lesion, accounting for 55.9 % of cases. Other types included anterior perineal anus (APA) in 20.6 %, anovestibular fistula (AVF) in 11.8 %, and Ano cutaneous fistula (ACF) in 11.8 %. Associated congenital anomalies were detected in 11 patients (32.4 %), most commonly cardiac malformations—atrial septal defect (ASD) or congenital heart disease (CHD) in 14.7 %—while others included VACTERAL association, sacral agenesis, and CNS/renal anomalies in 17.7 %. [Table 1] 2. Functional Outcome After Primary ASARP Table 2. Functional Outcome Parameters (n = 34) Parameter Category n ( %) Kelly score (5–6 = Good; 3–4 = Fair) 6 (Good) 24 (70.6) 5 (Good) 7 (20.6) 4 (Fair) 3 (8.8) Staining None (2) 25 (73.5) Occasional (1) 9 (26.5) Soiling None (2) 34 (100) Anal sphincter strength Strong (2) 30 (88.2) Weak (1) 4 (11.8) Bowel movement frequency GP A ≥ 1 / day, no soiling 16 (47.1) GP B ≥ 1 / day with soiling 8 (23.5) GP C < 1 / day 10 (29.4) Constipation None 23 (67.6) Occasional 4 (11.8) Yes 7 (20.6) Functional evaluation using the Kelly scoring system revealed excellent postoperative continence. The mean Kelly score was 5.62 ± 0.65, with 24 patients (70.6 %) scoring 6 and 7 patients (20.6 %) scoring 5, indicating good continence in 91 % of cases. Only 3 patients (8.8 %) had fair continence (score 4), and none had poor outcomes. Regarding anal cleanliness, 25 children (73.5 %) showed no staining, and 9 (26.5 %) had only occasional staining. Soiling was absent in all (100 %), confirming effective sphincter control and adequate neo-anal positioning. Anal sphincter tone assessment demonstrated strong muscle strength in 30 (88.2 %) patients and weak tone in 4 (11.8 %). Evaluation of bowel habits showed that 16 (47.1 %) passed stools at least once daily without staining (Group A), 8 (23.5 %) had more than one motion per day associated with some staining (Group B), and 10 (29.4 %) had less than one bowel movement per day (Group C). Constipation was absent in 23 (67.6 %), occasional in 4 (11.8 %), and persistent in 7 (20.6 %) of cases. These findings demonstrate that the vast majority of patients attained good voluntary bowel control, with a small subset requiring dietary or pharmacologic management for constipation.[Table 2] 3. Post-operative Complications Table 3. Post-operative and Intra-operative Complications (n = 34) Complication type Category n ( %) Intra-operative Vaginal tear 4 (11.8) None 30 (88.2) Post-operative None 30 (88.2) Wound infection 2 (5.9) Wound dehiscence 1 (2.9) Anal stenosis 1 (2.9) Bowel preparation Adequate (0 = adequate) 34 (100) Associated anomalies distribution No anomaly 23 (67.6) ASD 2 (5.9) CHD 3 (8.8) CHD + Prosencephaly 1 (2.9) Hydronephrosis + ASD 1 (2.9) Sacral agenesis 2 (5.9) VACTERAL association 2 (5.9) Pre-operative and postoperative morbidity was minimal. Intra-operative vaginal tear occurred in 4 patients (11.8 %), all of whom were repaired primarily with uneventful healing. Post-operative complications were observed in only 4 patients (11.8 %), comprising wound infection (5.9 %), wound dehiscence (2.9 %), and anal stenosis (2.9 %). None required reoperation, and all were managed conservatively with satisfactory recovery. Bowel preparation was adequate in all 34 cases (100 %), contributing to the low infection rate. No patient experienced life-threatening events or mortality.[Table 3] Overall, primary ASARP performed in infancy for vestibular-type anorectal malformations achieved excellent functional outcomes with minimal morbidity. Nearly all children attained social continence, characterized by good Kelly scores, absence of soiling, and strong sphincter tone. Minor complications were infrequent (12 %), short-lived, and had no long-term impact on continence or quality of life. The results support that single-stage ASARP is a safe, definitive corrective procedure providing durable functional and cosmetic results when meticulous surgical technique and adequate bowel preparation are ensured.

The present study demonstrated that primary anterior sagittal anorectoplasty (ASARP) provides excellent continence and low morbidity in female anorectal malformations (ARM) with vestibular fistula. A good continence rate of 91.2 % (Kelly ≥ 5) with no soiling and minimal staining (26.5 %) compares favorably with findings from several international studies. In an integrated clinical and MRI-based assessment, Abo-Halawa et al. (2025) evaluated 12 patients after ASARP for rectovestibular fistula and reported that the anorectal angle and striated-muscle integrity strongly correlated with continence outcomes (Spearman ρ = –0.831; p < 0.001). They concluded that optimal function depends on a more acute anorectal angle, intact muscle complex, and centralized neorectum.[7] The current series, in which 88.2 % showed strong sphincter tone and all achieved continence without soiling, aligns with these anatomical-functional correlations. The long-term multicenter series by Wakhlu et al. (2009) involving 1147 patients (mean follow-up 19 years) documented 95 % good results, 5 % complications, and 11 cases of anal stenosis, most of which resolved with dilatation.[8] Our complication rate of 11.8 % (infection 5.9 %, dehiscence 2.9 %, stenosis 2.9 %) is comparable, reinforcing that ASARP achieves stable continence with minimal morbidity even in resource-limited settings. Similarly, Chaudhary et al. (2010) performed ASARP on 48 female patients (0–14 years) with vestibular or perineal fistula and reported uniformly satisfactory outcomes, no colostomy requirement, and rapid recovery.[9] Their findings parallel ours, where all patients underwent single-stage correction without need for diversion, and the mean postoperative stay was 8.35 days. A broader evaluation by Hashizume et al. (2018) on 20 patients (both sexes) found voluntary bowel movements in 100 %, no soiling in females, and constipation in 33 %, recommending laxative therapy in half of cases.[10] Our study’s constipation rate of 20.6 % is lower, possibly reflecting uniform postoperative bowel-training protocols and early follow-up. In a large contemporary series of 594 patients, Zamir et al. (2020) reported anal stricture 5 %, rectal prolapse 3.4 %, and constipation 27 % by the end of the first postoperative year (reducing to 7 % at one year). Continence was good in 95.5 % of cases.[11] These outcomes are consistent with our data, confirming the reproducibility of ASARP results across diverse populations. Taken together, the cumulative evidence including the present study underscores that single-stage ASARP yields functional success rates exceeding 90 % with complication rates below 12 %. The preservation of sphincter integrity, centralization of the rectum, and meticulous perineal reconstruction are critical determinants of good outcome. Compared to multistage PSARP, ASARP offers distinct advantages: shorter hospital stay, avoidance of colostomy, excellent cosmetic appearance, and minimal long-term morbidity.

Primary ASARP in female children with vestibular-type anorectal malformations provides excellent continence, low complication rates, and superior cosmetic outcomes. With a good continence rate of over 90%, absence of soiling, and minimal wound morbidity, ASARP stands validated as a safe, single-stage, and effective corrective procedure. The procedure eliminates the need for colostomy, shortens hospitalization, and ensures satisfactory long-term function and appearance, making it the procedure of choice for vestibular fistula.

1. Stephen F D, Smith ED: Anatomy and function of the normal rectum and anus; individual deformities in the male; Operative management of anal deformities, in Stephen F D (eds): Anorectal Malformations in Children. Chicago, IL, Year Book, 1971, pp 212-273 2. Peňa A, de Vries P A: Posterior Sagittal anorectoplasty: important technical consideration and new applications. J Pediatr Surg 17:796-811, 1982 3. Okada A, Tamada H, Tsuji H, et al: Anterior sagittal anorectoplasty as a redo operation for imperforate anus. J Pediatr Surg 28:933-938, 1993 4. Wakhlu A, Pandey A, Prasad A, et al: Anterior sagittal anorectoplasty for anorectal malformations and perineal trauma in the female child. J Pediatr Surg 31:1236-1240, 1996 5. Kelly JH (1972) The clinical and radiological assessment of anal continence in childhood. Aus N Z J Surg 42:62–63 6. Elsawaf MI, Hashish MS. Anterior Sagittal Anorectoplasty with External Sphincter Preservation for the Treatment of Recto-vestibular Fistula: A New Approach. J Indian Assoc Pediatr Surg. 2018 Jan-Mar;23(1):4-9. doi: 10.4103/jiaps.JIAPS_2_17. PMID: 29386757; PMCID: PMC5772095. 7. Abo-Halawa N, Abdelrasheed A, Husein A, Elbatarny A, Ghieda U, Abohalawa M, et al. Functional Outcomes of Anterior Sagittal Anorectoplasty Repair for Rectovestibular Fistula: An Integrated Clinical and MRI-based Assessment – Initial Findings. J Pediatr Surg. 2025 Apr 1; 60(4):162156. 8. Wakhlu A, Kureel SN, Tandon RK, Wakhlu AK. Long-term results of anterior sagittal anorectoplasty for the treatment of vestibular fistula. J Pediatr Surg. 2009 Oct 1; 44(10):1913-9. 9. Chaudhary RP, Thapa B, Thana S, Singh PB. Single-stage anterior sagittal anorectoplasty (ASARP) for anorectal malformations with vestibular fistula and perineal ectopic anus in females: a new approach. J Nepal Paediatr Soc. 2010; 30(1):37-43. 10. Hashizume N, Asagiri K, Fukahori S, Ishii S, Saikusa N, Higashidate N, et al. Functional assessment of patients with perineal and vestibular fistula treated by anterior sagittal anorectoplasty. Afr J Paediatr Surg. 2018 Jan 1; 15(1):36-41. 11. Zamir N, Rasool N. The early outcome of primary anterior sagittal approach for low anorectal malformations in female patients. Pak J Med Sci. 2020 Mar; 36(3):456.