Caesarean section (CS) is the commonest major operation performed on women worldwide with progressively rising incidence. Consequently, long-term adverse sequelae due to uterine scar defect have been increasing. Given the association between uterine scar defect and gynecological symptoms, obstetric complications and potentially with subfertility, it is important to elucidate the etiology in order to develop preventive strategies. Surgical technique of uterine incision closure seems to be the most important determinant of defect formation. The aim of this prospective randomized study is to evaluate specifically the influence of inclusion versus exclusion of the endometrium during suturing the uterine incision on the risk to develop uterine scar defect.

Caesarean section (CS) is the commonest major operation performed on women worldwide with progressively rising incidence. Consequently, long-term adverse sequelae due to uterine scar defect have been increasing. Common gynecological complains include chronic pelvic pain, dyspareunia, dysmenorrhea and postmenstrual spotting and infertility. Obstetric sequelae seem to be increasing such as cesarean scar ectopic pregnancy, placenta previa, and placenta accrete, all associated with major maternal morbidity and even mortality. Given the association between uterine scar defect and gynecological symptoms, obstetric complications and potentially with subfertility, it is important to elucidate the etiology in order to develop preventive strategies. Probable risk factors suggested are single-layer myometrium closure, multiple CSs and uterine retroflexion, however, surgical technique of uterine incision closure seems to be the most important determinant of defect formation. It is proposed that continuous, non-locking absorbable sutures in two layers, without including much of decidua and without undue tight (constricting) pulling of sutures are likely to result in good healing of uterine scar. The aim of this prospective randomized study is to evaluate specifically the influence of inclusion versus exclusion of the endometrium during suturing the uterine incision on the risk to develop uterine scar defect.

Material and Methods Prospective randomized single blinded study conducted in a single tertiary center. All women at term (≥37 weeks of gestation) with singleton pregnancy that are about to go threw cesarean section attending the pre- operative clinics, will be offered to participate in the study. After signing informed consent, women will be block randomized for one of two groups: A- uterine incision repair including suturing of the endometrium, B - uterine incision repair without including the endometrium. All operation will be performed by a single highly skilled obstetrician. All other stages of operations will be similar in both of the groups including: low segment incision, delivery of the fetus and the placenta, uterine revision, intraperitoneal uterine repair, use of stratafix thread in double layer suturing. Operative and post operative data will be collected from the medical files including: operation duration, estimated blood loss, operation complications ( hypotension, bladder gut or vascular perforation ) , post operative complications ( hemorrhage, endometritis, vascular - thromboembolic event, ileus ). All women will be invited to the gynecologic clinics six month post operation for vaginal sonographic evaluation of the uterine scar and for filling questionnaire concerning possibility of uterine scar defect ( spotting, pelvic pain, fertility abnormalities ).

Inclusion Criteria:

• Term pregnancy (≥37 weeks of gestation)
• Elective CS

Exclusion Criteria:

• Uterine scar
• Thrombophilia
• Dysmorphic uterus
• Connective tissue disorder

Women

Women will not know which arm they were allocated to