RESUMEN

Objective:To investigate the correlation between the uterine incisional hematoma following cesarean section and scar diverticulum.Methods:This is a retrospective study involving 1 939 women who underwent cesarean section for the first time at the People's Hospital of Longhua Shenzhen from January 2020 to December 2021. Women with uterine incisional hematoma were selected as the hematoma group ( n=149) and were further divided into the dehiscence group, including patients with uterine incisional dehiscence caused by hematoma, and non-dehiscence group, including those without uterine incisional dehiscence. The patients without uterine incisional hematoma during the same period were selected as the control group ( n=110). The incidence of scar diverticulum after uterine incision healing and the long-term outcomes in the two groups were compared. Statistical analysis was performed using a t-test or Chi-square test. Results:(1) The incidence of uterine incisional hematoma was 7.7% (149/1 939). In the 149 cases with uterine incisional hematoma detected by postoperative ultrasonography, 74 were in the dehiscence group and 75 in the non-dehiscence group. (2) The number of women developing cesarean section scar diverticulum was 41, with an incidence of 2.1% (41/1 939), and all of them were in the hematoma group, accounting for 27.5% (41/149). The proportion of women who developed scar diverticulum in the dehiscence group was higher than that of the non-dehiscence group [52.7% (39/74) vs. 2.7% (2/75), χ2=35.96, P<0.001]. (3) The incidence of scar diverticulum in patients with uterine incisional dehiscence caused by intra-incision hematoma, intra- and posterior incision hematoma, as well as a combination of intra-, anterior, and posterior incision hematoma were 10/18, 55.1% (27/49), and 2/2, respectively. None of the five patients with uterine scar diverticulum were caused by anterior incision hematoma plus partial intra-incision hematoma. The incidence of scar diverticulum was 2.7% (2/75) in the non-dehiscence group. (4) Among the 41 cases with scar diverticulum, ultrasound re-examination by postpartum 6-24 months found that the results of 40 (97.6%) cases were consistent with the last ultrasound findings. A small "v"-shaped scar diverticulum was observed in another patient by ultrasound 42 d after delivery, which disappeared in a re-examination 13 months after surgery. Conclusions:Uterine incisional hematoma is associated with scar diverticulum following cesarean section. Uterine incisional dehiscence due to hematoma may be an influencing factor for diverticulum formation.