OBJECTIVE: To review systematically the medical literature reporting on the prevalence of a niche at the site of a Cesarean section (CS) scar using various diagnostic methods, on potential risk factors for the development of a niche and on niche-related gynecological symptoms in non-pregnant women. METHODS: The PubMed and EMBASE databases were searched. All types of clinical study reporting on the prevalence, risk factors and/or symptoms of a niche in non-pregnant women with a history of CS were included, apart from case reports and case series. RESULTS: Twenty-one papers were selected for inclusion in the review. A wide range in the prevalence of a niche was found. Using contrast-enhanced sonohysterography in a random population of women with a history of CS, the prevalence was found to vary between 56% and 84%. Nine studies reported on risk factors and each study evaluated different factors, which made it difficult to compare studies. Risk factors could be classified into four categories: those related to closure technique, to development of the lower uterine segment or location of the incision or to wound healing, and miscellaneous factors. Probable risk factors are single-layer myometrium closure, multiple CSs and uterine retroflexion. Six out of eight studies that evaluated niche-related symptoms described an association between the presence of a niche and postmenstrual spotting. CONCLUSIONS: The reported prevalence of a niche in non-pregnant women varies depending on the method of detection, the criteria used to define a niche and the study population. Potential risk factors can be categorized into four main categories, which may be useful for future research and meta-analyses. The predominant symptom associated with a niche is postmenstrual spotting.
OBJECTIVE: To review systematically the medical literature reporting on the prevalence of a niche at the site of a Cesarean section (CS) scar using various diagnostic methods, on potential risk factors for the development of a niche and on niche-related gynecological symptoms in non-pregnant women. METHODS: The PubMed and EMBASE databases were searched. All types of clinical study reporting on the prevalence, risk factors and/or symptoms of a niche in non-pregnant women with a history of CS were included, apart from case reports and case series. RESULTS: Twenty-one papers were selected for inclusion in the review. A wide range in the prevalence of a niche was found. Using contrast-enhanced sonohysterography in a random population of women with a history of CS, the prevalence was found to vary between 56% and 84%. Nine studies reported on risk factors and each study evaluated different factors, which made it difficult to compare studies. Risk factors could be classified into four categories: those related to closure technique, to development of the lower uterine segment or location of the incision or to wound healing, and miscellaneous factors. Probable risk factors are single-layer myometrium closure, multiple CSs and uterine retroflexion. Six out of eight studies that evaluated niche-related symptoms described an association between the presence of a niche and postmenstrual spotting. CONCLUSIONS: The reported prevalence of a niche in non-pregnant women varies depending on the method of detection, the criteria used to define a niche and the study population. Potential risk factors can be categorized into four main categories, which may be useful for future research and meta-analyses. The predominant symptom associated with a niche is postmenstrual spotting.
Authors: Sanne I Stegwee; Ângela J Ben; Mohamed El Alili; Lucet F van der Voet; Christianne J M de Groot; Judith E Bosmans; Judith A F Huirne Journal: BMJ Open Date: 2021-07-02 Impact factor: 2.692
Authors: A J M W Vervoort; L B Uittenbogaard; W J K Hehenkamp; H A M Brölmann; B W J Mol; J A F Huirne Journal: Hum Reprod Date: 2015-09-25 Impact factor: 6.918
Authors: A J M W Vervoort; L F Van der Voet; M Witmer; A L Thurkow; C M Radder; P J M van Kesteren; H W P Quartero; W K H Kuchenbecker; M Y Bongers; P M A J Geomini; L H M de Vleeschouwer; M H A van Hooff; H A A M van Vliet; S Veersema; W B Renes; H S van Meurs; J Bosmans; K Oude Rengerink; H A M Brölmann; B W J Mol; J A F Huirne Journal: BMC Womens Health Date: 2015-11-12 Impact factor: 2.809