Background: Modern obstetrics must meet many challenges, including long-term complications resulting from the presence of a uterine niche after cesarean section.
Objectives: To assess the impact of selected risk factors on the uterine healing process after cesarean section. The uterus was closed with a single-layer continuous suture covering the entire thickness of the myometrium, excluding the decidua.
Material and methods: A prospective, case-controlled study was carried out at 2nd Department of Gynecology and Obstetrics, Wroclaw Medical University, Poland. Women who delivered by cesarean section at our Department were invited to undergo an ultrasonographic assessment of the cesarean section scar from 6 to 9 weeks after the procedure. In all cases, the uterus was closed with a single-layer continuous suture. The ultrasound examination of the niche was performed according to the modified Delphi protocol. The volume of the niche was calculated and a 3D model was created. The obtained data were analyzed with clinical information from the maternal medical history and the course of the pregnancy.
Results: A total of 204 patients participated in the study. Five patients had a residual myometrial thickness (RMT) <2.2 mm and 35 had a residual myometrial thickness to adjacent myometrial thickness ratio (RMT/AMT) ≤0.5. In 45% of women, pregnancy course was complicated by gestational diabetes mellitus (GDM), gestational hypertension and hypothyroidism. The cervical canal was colonized with pathogenic flora in 22% of women. No correlation between maternal and gestational age at delivery, presence of medical complications during pregnancy, colonization of the cervical canal, and presence of niche and its parameters were found.
Conclusions: Our study revealed that the selected risk factors, such as systemic diseases during pregnancy and in the maternal medical history, as well as the colonization of the cervical canal, have no impact on uterine scar healing in women undergoing single-layer uterine closure spanning the entire thickness of the myometrium, excluding the decidua.
Keywords: 3D ultrasonography; cesarean scar niche; risk factors of cesarean scar niche; single-layer suture; systemic diseases during pregnancy.