Masculinizing Gender-Affirming Surgery
Masculinizing genital gender-affirming surgery (GAS) is governed by the WPATH Standards of Care v8 (2022), the ACOG 2021 Committee Opinion, the Endocrine Society 2017 Clinical Practice Guideline, and the AAFP 2023 Position Paper. This page focuses on the genitourinary / reconstructive-urologic component — metoidioplasty, phalloplasty (with or without urethral lengthening), vaginectomy, scrotoplasty, testicular implants, and erectile prosthesis. Top-surgery / chest masculinization sits outside the reconstructive-urologic scope and is covered in the Masculinizing Procedures clinical-conditions article.[1][2][3]
The masculinizing GAS plan hinges on four explicit patient priorities: (1) standing micturition (drives urethral lengthening), (2) penetrative intercourse (drives phalloplasty + erectile prosthesis), (3) aesthetic phallus size (metoidioplasty ~5.6 cm vs phalloplasty ~14 cm), and (4) tolerance for staged morbidity (metoidioplasty single-stage with markedly lower complications vs phalloplasty multi-stage with high urethral burden).[1][2][4] The contemporary decision anchors are WPATH SOC v8 for eligibility and timing, the Bordas 2021 Front Endocrinol 813-patient metoidioplasty series, the Wang 2026 Microsurgery flap-vs-flap complication-rate analysis, the Berli 2025 Big Ben method two-stage urethral lengthening (27% urologic complication rate; 96% standing micturition), the Veerman 2020 and Waterschoot 2021 complication-rate publications for phalloplasty and metoidioplasty respectively, and Pigot / Levy 2026 consensus on penile-implant timing and technique.[5][6][7][8][9]
Decision Framework
Goal-Directed Pathway Selection
| Patient Priority | Recommended Pathway | Alternative | Rationale |
|---|---|---|---|
| Standing micturition without penetrative function; minimize complications | Metoidioplasty with urethral lengthening (UL) | Phalloplasty + UL (overkill if penetrative function is not a goal) | Single-stage; preserves erogenous sensation (4.8/5 satisfaction); lower urethral complication rates than phalloplasty[2][10] |
| Standing micturition + penetrative intercourse | Phalloplasty + UL (staged), erectile prosthesis at 9–12 mo | Metoidioplasty first → conversion to phalloplasty later (option preserved) | Phalloplasty alone is non-functional for penetration without prosthesis; staged sequencing minimizes infection and prosthetic failure[1][11] |
| Penetrative intercourse without standing micturition | Phalloplasty without UL + perineal urethrostomy + erectile prosthesis | Metoidioplasty + phalloplasty conversion | Markedly lower urethral complication rates when UL is omitted (UL is the single strongest predictor of fistula OR 6.07 / stricture OR 24.5; Waterschoot 2021)[6] |
| Maximal sensation prioritized; size acceptable | Metoidioplasty | Phalloplasty (sensation 3.4/5; with neurorrhaphy can recover) | Metoidioplasty preserves native clitoral neurovasculature; sensation 4.8/5 (Robinson 2021)[10] |
| Active smoker | Defer all UL until cessation ≥4–6 weeks documented | Metoidioplasty without UL or phalloplasty without UL while in cessation program | Smoking is the strongest modifiable risk factor — fistula OR 6.54, permanent fistula OR 3.76 (Waterschoot)[6] |
| Uncertain / wants to preserve pathway flexibility | Metoidioplasty as first operation | — | Phalloplasty conversion remains feasible after metoidioplasty; the reverse is rarely possible[2] |
Phalloplasty Flap Selection
| Clinical Scenario | First-Line Flap | Alternative(s) | Avoid |
|---|---|---|---|
| Default candidate; values aesthetics + sensation | Radial forearm free flap (RFFF) with tube-in-tube urethra (highest sensation; Garaffa 2010 UCL standing-tip-voiding 99%) | Pedicled ALT (concealed donor site) | Tube-in-tube ALT (D'Arpa: feasible in only 5.8% of harvests) |
| Wants concealed donor site, accepts debulking | Pedicled ALT with separate-flap urethra | RFFF with cosmetic forearm-scar counseling | ALT with single-stage tube-in-tube urethra |
| Lowest overall complication rate prioritized | Pedicled abdominal flap (Wang 2026 microsurgery — lowest overall complication 40.9%) | RFFF | Free-flap when patient cannot tolerate microsurgical operating time |
| Contemporary urethral-stricture optimization | Two-stage "Big Ben Method" (Berli 2025 — stricture 8%; fistula 16.4%; standing micturition 96%) | Single-stage RFFF | Single-stage tube-in-tube in active smokers |
| Intrinsic rigidity preferred (no prosthesis required) | Fibula osteocutaneous free flap (limited centers) | RFFF + delayed IPP | Fibula in patients with peripheral vascular disease |
| Microsurgery not available / contraindicated | Pedicled ALT or pedicled abdominal flap | — | RFFF / fibula at non-microsurgical centers |
Urethral Lengthening Decision
| Clinical Scenario | First-Line | Alternative | Avoid |
|---|---|---|---|
| Standing micturition desired + non-smoker + adequate vaginal-wall tissue | Full UL with anterior vaginal-wall flap + labia minora flaps + buccal mucosa graft (modified Belgrade for metoidioplasty); RFFF tube-in-tube or two-stage Big Ben for phalloplasty | UL with pre-laminated buccal mucosa onto the phalloplasty flap | UL in active smoker (defer) |
| Standing micturition desired + previously failed UL | Staged repair with BMG urethroplasty (Sterling 2023 transmeatal ventral inlay; Daneshvar 2020 multi-institution validation) | Conversion to perineal urethrostomy | Repeat single-stage UL |
| Penetrative function only; standing micturition not required | Phalloplasty without UL + perineal urethrostomy (~5× lower complication rate) | Metoidioplasty without UL | Urethral lengthening "just in case" |
| Preserves vaginal canal; non-binary anatomical goals | Metoidioplasty without UL or vaginectomy | Shaft-only phalloplasty with vaginal preservation (Chen, Moorefield) | Coercive vaginectomy when not patient-aligned |
Vaginectomy Timing & Technique
| Clinical Scenario | First-Line | Alternative | Avoid |
|---|---|---|---|
| Phalloplasty with UL planned | Concurrent transperineal vaginectomy with anterior-vaginal-wall flap preserved for UL (sharp excision; Hougen 2020)[15] | Electrocautery fulguration (Ho 2025; equivalent outcomes, shorter OR time, lower EBL)[16] | Skipping vaginectomy when UL is planned (high fistula risk) |
| Metoidioplasty + UL planned | Optional vaginectomy based on dysphoria-burden weighting — fulguration preferred for shorter OR / EBL | Sharp excision when AVW flap is needed for UL | Mandating vaginectomy for all UL candidates |
| Metoidioplasty without UL | Optional vaginectomy — patient-aligned dysphoria-driven decision | Vaginectomy deferred indefinitely | Coercive vaginectomy |
| Non-binary patient retaining vaginal canal | No vaginectomy | — | Vaginectomy as default in non-binary care |
| Concurrent laparoscopic hysterectomy | Laparoscopic-assisted vaginectomy (Gomes da Costa 2016 — vaginal mucosa preserved for UL in 100%)[17] | Two-stage (laparoscopic hysterectomy → later transperineal vaginectomy) | Open vaginectomy when laparoscopic platform is available |
Scrotoplasty, Testicular Implants, Erectile Prosthesis (Staged Sequencing)
| Stage | Operation | Timing | Notes |
|---|---|---|---|
| Stage 1 | Hysterectomy ± BSO | Months 0–6 (before genital surgery if UL planned) | Laparoscopic in ~96.5% of cases; vaginal approach is technically challenging due to testosterone-induced vaginal atrophy and absent uterine descent. Oophorectomy decision is patient-specific (fertility, hormone plans). Few patients change testosterone dosing after HBSO regardless of BSO[4] |
| Stage 2 | Vaginectomy + scrotoplasty + metoidioplasty or phalloplasty ± UL | Months 6–12 | Hoebeke pedicled-labia-majora U-flap scrotoplasty (most-common; explant 11.5% vs 20.8% other techniques); Pigot 2020 stepwise scrotoplasty without UL[12][18] |
| Stage 3 (if phalloplasty) | Testicular implants | ≥6 mo after scrotoplasty | Trend toward smaller / lighter prostheses + delayed implantation has reduced complications. Smoking is a major risk factor[12] |
| Stage 4 (if phalloplasty) | Erectile prosthesis (3-piece IPP preferred; ZSI 100 FtM or malleable as alternatives) | 9–12 mo after phalloplasty | Levy 2026 consensus protocol: confirm flap vascularity + reliable micturition before proceeding; cylinder wrapping + pubic-bone fixation are critical; 5-yr retention 42–78%; 83.9% achieve penetration. Sun 2023 infrapubic malleable in transmen; Pigot 2020 ZSI 100 FtM cohort[9][13][19][20] |
Long-Term Urologic Surveillance
All patients with UL require lifelong urologic follow-up. Red flags for urgent referral: urinary retention, postvoid dribbling, pelvic pain or fullness, recurrent UTI, persistent vaginal cavity, or cuffing of the neomeatus. Urethral complications may present weeks to years after the index operation.[3][14]
Treatment Database
| Procedure | Domain | Notes |
|---|---|---|
| Simple Metoidioplasty | Phallic Construction | Clitoral release + suspensory-ligament division + degloving without UL. Preserves native voiding anatomy. Mean phallus ~5.6 cm. Sensation 4.8/5 (Robinson 2021). Single-stage; lowest urethral complication burden. |
| Modified Belgrade Metoidioplasty | Phallic Construction | Clitoral release + UL with anterior vaginal-wall flap + labia-minora flap(s) + buccal mucosa graft. Bordas 2021: 813-pt series. Standing micturition achieved in most patients near IBW. UL is the strongest predictor of urethral complications (Waterschoot OR 15.5). |
| RFFF Phalloplasty | Phallic Construction | Reference standard for aesthetics + sensation. Tube-in-tube urethra. Garaffa 2010 UCL 115-pt landmark: 97% flap survival, 99% standing-tip-voiding. Highest urethral-complication rates: fistula ~48%, stricture ~44%. Visible forearm scar. |
| ALT Phalloplasty | Phallic Construction | Concealed donor site; no microsurgery required. Tube-in-tube urethra feasible in only 5.8% of harvests (D'Arpa). Higher fistula odds vs RFFF (OR 2.50 in some series). Often requires debulking. Best when SCIP-augmented urethra is used (D'Arpa hierarchy). |
| Phalloplasty — Pedicled Abdominal Flap | Phallic Construction | No microsurgery. Wang 2026 Microsurgery: lowest overall complication rate 40.9%; fewer fistulas + strictures than RFFF / ALT in flap-vs-flap analysis. Separate-flap urethra. Trade-off: variable sensation. |
| Phalloplasty — SCIP Flap | Phallic Construction | Concealed groin / flank donor site; usually primary donor closure. Most useful as a separate urethral flap for ALT or revision phalloplasty. D'Arpa 93-pt ALT urethral-reconstruction series: SCIP urethra complication rate 26.3%. De Gelder 2025: 55 SCIP flaps, 82% standing voiding after SCIP urethra, 0 shaft-flap failures. |
| Fibula Phalloplasty | Phallic Construction | Osteocutaneous free fibula flap with vascularized bone for intrinsic rigidity, potentially avoiding erectile prosthesis. Requires microsurgery, staged prelaminated urethra, mandatory lower-leg vascular imaging, and acceptance of permanent rigidity plus donor-leg morbidity. |
| "Big Ben Method" — Two-Stage Urethral Lengthening Phalloplasty | Phallic Construction | Berli 2025 Plast Reconstr Surg: total urologic complication 27% (stricture 8%, fistula 16.4%); 96% standing micturition. Potentially lower stricture rate than single-stage approaches (historical 32–63%). |
| Pars Fixa Urethral Construction | Urethral Reconstruction | Fixed perineal urethra from native meatus to phallus base. Usually anterior vaginal-wall flap with labia minora / vestibular / bulbospongiosus buttress; junction with pars pendulans is the dominant stricture site. |
| Phallic (Pendulous) Urethra — Tube-in-Tube | Urethral Reconstruction | Single-flap pars pendulans construction within the phalloplasty flap, classically RFFF. Thin hairless tissue and offset suture lines are the key success variables; ALT usually needs staged graft or separate-flap urethra. |
| Phallic Urethra — Prelaminated Buccal Mucosa Graft | Urethral Reconstruction | Staged mucosal graft prefabrication of the pars pendulans. Biologically attractive, but clinical prelaminated-flap outcomes are worse than tube-in-tube in meta-analysis; BMG is stronger as secondary stricture-repair tissue. |
| Phallic Urethra — Separate Flap (e.g., SCIP, ALT-perforator) | Urethral Reconstruction | Dedicated urethral flap distinct from the shaft flap, usually for ALT phalloplasty. SCIP has the strongest non-tube-in-tube signal in D'Arpa's 93-case ALT series (26.3% urethral complications). |
| Perineal Urethrostomy (no UL) | Urethral Reconstruction | Voiding from perineum; dramatically lower urethral complication rates. Acceptable when standing micturition is not a patient priority. Used with phalloplasty without UL or after failed UL. |
| Vaginectomy — Transperineal Sharp Excision | Vaginectomy | Hougen 2020: median OR ~135 min, EBL ~250 mL. Peritoneal entry in 44% (closed primarily without sequelae). AVW mucosa preserved as flap for UL in 83%. Preferred when AVW flap is needed. |
| Vaginectomy — Electrocautery Fulguration | Vaginectomy | Ho 2025 J Sex Med: significantly shorter OR (183 vs 290 min, p<0.05) and lower EBL. Equivalent surgical outcomes vs sharp excision. Preferred when AVW tissue is not required for UL. |
| Vaginectomy — Laparoscopic-Assisted | Vaginectomy | Gomes da Costa 2016: continuation of laparoscopic hysterectomy. Mean OR 155 min. Adequate vaginal mucosa obtained for urethral reconstruction in 100% of cases. Preferred when concurrent laparoscopic HBSO. |
| Scrotoplasty — Hoebeke Pedicled-Labia-Majora U-Flap | Scrotoplasty | Cranially pedicled U-shaped labia-majora flaps rotated 90° medially with pedicled-fat-pad bulkiness. Most-frequently performed technique. Pigot 2019: explant rate 11.5% (vs 20.8% across all techniques). |
| Scrotoplasty — Horseshoe Pubic Flap | Scrotoplasty | Used when UL is not performed; incorporates clitoral hood + labia-majora flaps. Pigot 2020 stepwise approach. |
| Testicular Implants | Testicular Implants | Placed ≥6 months after scrotoplasty for tissue maturation. Long-term explant rate 20.8% overall (infection / extrusion / discomfort / leakage). Trend toward smaller, lighter prostheses + delayed implantation has reduced complications. Smoking is a major risk factor. |
| Erectile Prosthesis — 3-Piece IPP (after phalloplasty) | Erectile Prosthesis | Most commonly used (83.6% of implants). 5-yr retention 42–78% in neophallus (lower than native penis). Levy 2026 consensus: confirm flap vascularity + reliable micturition before proceeding; cylinder wrapping + pubic-bone fixation are critical. 60% retain original implant; 83.9% achieve penetration (Rooker SR). |
| Erectile Prosthesis — Malleable (infrapubic insertion) | Erectile Prosthesis | Sun 2023 single-surgeon n=107: revision rate 16%. No neophallus erosions reported with infrapubic approach. Simpler mechanism; useful when manual dexterity or cost favor malleable. |
| Erectile Prosthesis — ZSI 100 FtM (transgender-specific malleable) | Erectile Prosthesis | First prosthesis designed specifically for transgender men. Pigot 2020 early explant rate 32% (infection / protrusion / pubic pain); 93% of those retaining the implant achieved penetrative intercourse. |
| Hysterectomy ± Bilateral Salpingo-Oophorectomy (HBSO) | Hysterectomy / BSO | Laparoscopic in ~96.5% of cases. Often a prerequisite for vaginectomy + UL in phalloplasty. Vaginal approach is technically challenging due to testosterone-induced vaginal atrophy and absent uterine descent. Oophorectomy decision is patient-specific (fertility, hormone plans). Few patients change testosterone dosing after HBSO regardless of BSO. |
See Also
- GAS Overview (Special Populations)
- Masculinizing Procedures (Special Populations)
- Revision & Salvage GAS
- Pharmacology — Gender-Affirming Hormone Therapy
- Foundations — Radial Forearm Free Flap
- Foundations — Anterolateral Thigh Flap
- SCIP Phalloplasty
- Fibula Phalloplasty
- Foundations — SCIP Flap
- Foundations — Buccal Mucosa Graft
- Penile Implants
References
1. Coleman E, Radix AE, Bouman WP, et al. Standards of Care for the Health of Transgender and Gender Diverse People, Version 8 (WPATH SOC v8). Int J Transgend Health. 2022;23(Suppl 1):S1–S259. doi:10.1080/26895269.2022.2100644
2. American College of Obstetricians and Gynecologists. Health care for transgender and gender diverse individuals. Committee Opinion No. 823. 2021. (Cronin B, Stockdale CK, eds.)
3. Jackson Q, Yedlinsky NT, Gray M. Lifelong care of patients after gender-affirming surgery. Am Fam Physician. 2024;109(6):560–565.
4. Berli JU, Knudson G, Fraser L, et al. What surgeons need to know about gender confirmation surgery when providing care for transgender individuals: a review. JAMA Surg. 2017;152(4):394–400. doi:10.1001/jamasurg.2016.5549
5. Bordas N, Stojanovic B, Bizic M, Szanto A, Djordjevic ML. Metoidioplasty: surgical options and outcomes in 813 cases. Front Endocrinol. 2021;12:760284. doi:10.3389/fendo.2021.760284
6. Waterschoot M, Hoebeke P, Verla W, et al. Urethral complications after metoidioplasty for genital gender affirming surgery. J Sex Med. 2021;18(7):1271–1279. doi:10.1016/j.jsxm.2020.06.023
7. Wang E, Cleff B, Basta A, et al. Flap choice in gender-affirming phalloplasty affects postoperative complication rates. Microsurgery. 2026;46(1):e70154. doi:10.1002/micr.70154
8. Berli JU, Ferrin PC, Buuck C, et al. Long-term urologic outcomes using the Big Ben method for phalloplasty. Plast Reconstr Surg. 2025. doi:10.1097/PRS.0000000000012010
9. Levy M, Falcone M, Bohr J, et al. Penile implants after phalloplasty in transgender individuals: a consensus-based surgical clinical protocol concerning pre-, peri-, and postoperative care. J Sex Med. 2026;23(2):qdaf365. doi:10.1093/jsxmed/qdaf365
10. Robinson IS, Blasdel G, Cohen O, Zhao LC, Bluebond-Langner R. Surgical outcomes following gender-affirming penile reconstruction: patient-reported outcomes from a multi-center, international survey of 129 transmasculine patients. J Sex Med. 2021;18(4):800–811. doi:10.1016/j.jsxm.2021.01.183
11. Veerman H, de Rooij FPW, Al-Tamimi M, et al. Functional outcomes and urological complications after genital gender-affirming surgery with urethral lengthening in transgender men. J Urol. 2020;204(1):104–109. doi:10.1097/JU.0000000000000795
12. Pigot GLS, Al-Tamimi M, Ronkes B, et al. Surgical outcomes of neoscrotal augmentation with testicular prostheses in transgender men. J Sex Med. 2019;16(10):1664–1671. doi:10.1016/j.jsxm.2019.07.020
13. Rooker SA, Vyas KS, DiFilippo EC, et al. The rise of the neophallus: a systematic review of penile prosthetic outcomes and complications in gender-affirming surgery. J Sex Med. 2019;16(5):661–672. doi:10.1016/j.jsxm.2019.03.009
14. Blasdel G, Dy GW, Nikolavsky D, et al. Urinary reconstruction in genital gender-affirming surgery: checking our surgical complication blind spots. Plast Reconstr Surg. 2024;153(4):792e–803e. doi:10.1097/PRS.0000000000010813
15. Hougen HY, Shoureshi PS, Sajadi KP. Gender-affirming vaginectomy — transperineal approach. Urology. 2020;144:263–265. doi:10.1016/j.urology.2020.05.084
16. Ho P, Schmidt-Beuchat E, Sljivich M, et al. Impact of vaginectomy technique on the outcomes of transmasculine gender-affirming surgery. J Sex Med. 2025:qdaf148. doi:10.1093/jsxmed/qdaf148
17. Gomes da Costa A, Valentim-Lourenço A, Santos-Ribeiro S, et al. Laparoscopic vaginal-assisted hysterectomy with complete vaginectomy for female-to-male genital reassignment surgery. J Minim Invasive Gynecol. 2016;23(3):404–409. doi:10.1016/j.jmig.2015.12.014
18. Pigot GL, Al-Tamimi M, van der Sluis WB, et al. Scrotal reconstruction in transgender men undergoing genital gender-affirming surgery without urethral lengthening: a stepwise approach. Urology. 2020;146:303. doi:10.1016/j.urology.2020.09.017
19. Sun HH, Isali I, Mishra K, et al. Surgical outcomes at a single institution of infrapubic insertion of malleable penile prosthesis in transmen. Urology. 2023;173:209–214. doi:10.1016/j.urology.2023.01.001
20. Pigot GLS, Sigurjónsson H, Ronkes B, Al-Tamimi M, van der Sluis WB. Surgical experience and outcomes of implantation of the ZSI 100 FtM malleable penile implant in transgender men after phalloplasty. J Sex Med. 2020;17(1):152–158. doi:10.1016/j.jsxm.2019.09.019