Hysteroscopic and laparoscopic management of caesarean scar (niche) defects in symptomatic patients

Abstract

Introduction: Worldwide, rates of caesarean section are rising. The term ‘niche’ describes the presence of an hypoechoic area within the myometrium of the lower uterine segment, reflecting a discontinuation of the myometrium at the site of a previous caesarean section. A defect in caesarean section scar is associated with symptoms like abnormal uterine bleeding, infertility and complications in subsequent pregnancy including: risk of rupture and morbidly adherent placenta. It can also increase rates of complications during gynaecological procedures: IUCD insertion, evacuation of retained products of conception, hysteroscopy and risk of ectopic pregnancy at scar site.Aims: To assess the use of surgical techniques to repair niche defects in symptomatic patients, with regards to operative complications, symptomatic relief, postop lower segment thickness and fertility.Methods: Patients were identified between August 2015–March 2017. Inclusion criteria: Patients who had one previous caesarean section, symptomatic i.e. abnormal uterine bleeding, dysmenorrhoea, dyspareunia, infertility. Exclusion criteria: Asymptomatic patients. No previous caesarean section.Results: Between August 2015 and March 2017, six patients underwent surgical management of niche defect. Four patients reported post menstrual bleeding, one patient had infertility and one had intermenstrual bleeding and dyspareunia. All patients had one caesarean section previously. Mean lower segment measurement preoperatively was 2.5 mm ± 1.6 mm. EBL intraoperatively was 130 ml (10–180 ml). Mean operating time was 90 mins (70–150 min). One patient was pregnant after niche repair and delivered by CS at 38 w. In all six cases, TVS in 3–5 months after surgery revealed restored lower segment to normal thickness 9.2 mm ± 1.8 mm. Symptom resolution was noted in all patients. There were no operative complications.Conclusions: Anterior uterine wall should be explored in the case of symptomatic patients with previous caesarean section scar. Hysteroscopic resection should not be proposed when RMT is <3 mm. Laparoscopic/vaginal repair allows restoration of the anatomy of the lower uterine segment when residual myometrium is <3 mm. Laparoscopic repair allows antefixation in cases of retroverted uterus. Consideration of a surgical approach should be determined by the patient's plans for fertility and by niche thickness. For women who do not desire pregnancy and whose niche thickness is >3 mm, a hysteroscopic approach should be considered. Women with symptomatic caesarean scar defects who do not desire fertility may also be candidates for hysterectomy. Patients who desire future fertility, especially those with <3 mm of myometrium at the niche site, should undergo laparoscopic resection.