BILAP HERNIA trial: a register-based randomized controlled multicenter trial of asymptomatic contralateral hernias undergoing endo-laparoscopic repair
Ramia Stolt, Hanna de la Croix, Johanna Österberg, Ursula Dahlstrand, Henrik Holmberg, Gabriel Sandblom, Pär Nordin, Maria MelkemichelAbstract
Introduction
The management of asymptomatic contralateral inguinal hernias in patients with bilateral inguinal hernias still remains debated. Most bilateral hernias are repaired simultaneously as endo-laparoscopic approach gain popularity, yet no consensus exists on the optimal timing of repair for the asymptomatic contralateral hernia.
Methods
A prospective, multicenter, register-based, randomized, clinical, non-inferiority trial will enroll 2200 adult men and women, with bilateral inguinal hernias, one asymptomatic, from Swedish units participating in the Swedish Hernia Register. Starting in 2026, randomization via the register will assign patients to either simultaneous endo-laparoscopic bilateral repair or unilateral repair of only the symptomatic hernia. All follow-up will occur via the register. The primary outcome is chronic pain at 1 year. Secondary outcomes include complications, reoperations for recurrence, elective or emergency repair of the asymptomatic hernia, patient satisfaction and operative time.
Discussion
No randomized trials have evaluated outcomes in patients with bilateral hernias and one asymptomatic, leaving surgeons without clear protocols. Watchful waiting is recommended for men with asymptomatic hernias due to concerns about chronic pain. This approach is less favored in women because of higher incidence of femoral hernias, despite them reporting higher pain rates after surgery. High-volume centers tend to perform simultaneous bilateral repairs without solid evidence. If the trial shows no significant difference in outcomes, bilateral repair could become standard, reducing future surgeries and health costs. The trial also offers a unique opportunity to investigate watchful waiting in women. It is expected that the results will inform future guidelines and clinical practice in bilateral inguinal hernia management.