Incidence of gynecological fistula and its surgical treatment: A national registry-based study

Introduction - Gynecological fistula (affecting female genital organs) leads to involuntary loss of urine or feces. In industrialized societies, fistulas occur mostly as complications of surgery, radiation therapy or inflammatory bowel disease. We sought to determine the incidence of gynecological fistula and type of surgical treatment provided in Norway. Material and methods - This was a retrospective national cohort study of women treated for gynecological fistula (International Classification of Disease‐10 code N82) during 2008‐2014, identified from the mandatory Norwegian Patient Registry. To compare groups, we utilized Chi‐square or non‐parametric tests. Results - In all, 1627 women (.06% of the female Norwegian population) had 4475 hospital admissions with a diagnosis of gynecological fistula. In total, 1214/1627 (75%) had fistula as the main diagnosis: 346 (29%) a urogenital fistula, 672 (55%) an enterogenital, 38 (3%) a genitocutaneous and 22 (2%) both urinary and enteral fistula. Surgery for gynecological fistula was performed in 723 women, an incidence rate of 4.2 per 100 000 person‐years (95% confidence interval [CI] 4.2‐4.3); gynecological procedures (mostly vaginal/perineal) were performed in 163 women (23%), urological in 43 (6%), enteral in 267 (37%) and surgery involving multiple pelvic compartments in 250 (35%). Women undergoing fistula surgery had a median of three hospital contacts (95% CI 3‐3), for 370 women (52%), the procedure was performed by a gynecologist, and 212 of these (29%) were also operated by urologists or gastroenterologists. Conclusions - Gynecological fistula is rare in Norway, with an overall incidence of 6/10 000 in the female population, whereas the incidence of surgically treated fistula is 4.2/100 000. However, the condition represents considerable morbidity for the individual patient