Caesarean section greatly increases risk of scar endometriosis

Objective: To estimate the incidence of scar endometriosis after different surgical procedures. Study design: A retrospective study of 72 patients diagnosed with scar endometriosis between 1978 and 2003 was performed. Patient age, site of endometriosis, previous operations, time-gap between last surgery and onset of symptoms, nodule characteristics, and recurrence were evaluated. Results: Age ranged from 16 to 48 years. Location varied according to the previous surgery: 46 caesarean section, one hysterectomy, one in abdominal surgery, 19 episiotomy, one was a relapse and two pelvic floor procedures, two women with no previous surgery. The incidence of scar endometriosis after caesarean section was significantly higher than after episiotomy (0.2 and 0.06%, respectively: p < 0.00001) with a relative risk of 3.3. Pain was the most frequent symptom. The mean time between surgery and onset of symptoms was 3.7 years. Conclusion: Our findings confirm that scar endometriosis is a rare condition and indicate, probably for the first time, that caesarean section greatly increases the risk of developing scar endometriosis. (c) 2010 Elsevier Ireland Ltd. All rights reserved.