Cesarean scar niche, fertility and uterine rupture during labor-A retrospective study

Objectives: To determine how does a uterine niche diagnosed prior to conception, affects future fertility and obstetrical outcomes, in a group of patients with secondary infertility undergoing fertility treatments.Study design: A retrospective case-control study was performed, recruiting patients after cesarean delivery, before fertility treatment. Using stored ultrasound photos and video loops, we determined niche's sonographic pa-rameters during the preconception period and retrieved the fertility and obstetrical outcomes thereafter.Results: 104 patients met the inclusion criteria, and 86 were available for analysis. 56 (65%) had uterine niches larger than 2 mm in depth, and 30 (34%) had a uterine scar of 2 mm or less. Demographic characteristics were not different between groups. No statistically significant differences were observed regarding rates of implan-tation and clinical pregnancy between the groups. There were four cases of cesarean scar rupture during failed trial of labor (TOLAC), all of which were in the group with larger than 2 mm niche (33% of all TOLAC cases in the respected group).Conclusions: While it appears that pre-conception presence of uterine niches larger than 2 mm in depth does not adversely affect future fertility, these niches might serve as a risk factor for future uterine rupture during TOLAC.