{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T14:48:24Z","timestamp":1782485304960,"version":"3.54.5"},"reference-count":36,"publisher":"BMJ","issue":"8","license":[{"start":{"date-parts":[[2021,8,29]],"date-time":"2021-08-29T00:00:00Z","timestamp":1630195200000},"content-version":"unspecified","delay-in-days":28,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"name":"Shanghai Municipal Key Clinical Specialty","award":["shslczdzk01802"],"award-info":[{"award-number":["shslczdzk01802"]}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program","doi-asserted-by":"crossref","award":["2018YFC1002102"],"award-info":[{"award-number":["2018YFC1002102"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Medical innovation research project of the 2020 \"Science and Technology Innovation Action Plan\" of Shanghai Science and Technology Commission","award":["20Y11907700"],"award-info":[{"award-number":["20Y11907700"]}]},{"name":"Research Project of Shanghai Health and Fitness Commission","award":["20184Y0344"],"award-info":[{"award-number":["20184Y0344"]}]},{"name":"Research Project of Shanghai Health and Fitness Commission","award":["201940012"],"award-info":[{"award-number":["201940012"]}]},{"name":"Medical Engineering Cross Funds from Shanghai Jiao Tong University","award":["YG2017QN38"],"award-info":[{"award-number":["YG2017QN38"]}]},{"name":"Medical Engineering Cross Funds from Shanghai Jiao Tong University","award":["YG2021ZD31"],"award-info":[{"award-number":["YG2021ZD31"]}]},{"name":"Medical Engineering Cross Funds from Shanghai Jiao Tong University","award":["ZH2018QNA36"],"award-info":[{"award-number":["ZH2018QNA36"]}]},{"name":"Clinical Science and Technology Innovation Project of Shanghai Hospital Development Center","award":["SHDC22020216"],"award-info":[{"award-number":["SHDC22020216"]}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2021,8,12]]},"published-print":{"date-parts":[[2021,8]]},"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Recently, the rate of caesarean sections (CS) worldwide has risen and CS-associated complications such as niche have increased substantially. Until now, evidence-based clinical guidelines for the treatment of niche-related symptoms remain absent. In patients with postmenstrual spotting, it has not been studied if the effect of levonorgestrel 52\u2009mg intrauterine system (LNG-IUS 52\u2009mg) is superior to that of hysteroscopy. This study will answer the question of whether LNG-IUS 52\u2009mg is more effective in improving postmenstrual spotting than hysteroscopic niche resection in women with niche-related spotting at 6 months after randomisation.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods and analysis<\/jats:title>\n                    <jats:p>This is a randomised controlled trial. A total of 208\u2009women with postmenstrual spotting related to niche in the caesarean uterine scar of at least 2\u2009mm and residual myometrium of at least 2.2\u2009mm evaluated by MRI will be included. Women desiring to conceive within 1\u2009year, with contraindications for LNG-IUS 52\u2009mg or hysteroscopic surgery will be excluded. After informed consent is obtained, eligible women will be randomly allocated to LNG-IUS 52\u2009mg or hysteroscopic niche resection at 1:1. The primary outcome is the efficacy in reducing postmenstrual spotting at 6\u2009months after randomisation. The secondary outcomes include menstrual pattern, total days of blood loss per month, rate of amenorrhoea, side effects and complications.We will use a Visual Analogue Scale for chronic pelvic pain, urological symptoms and women\u2019s satisfaction (five-point Likert scale).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Ethics and dissemination<\/jats:title>\n                    <jats:p>The study was approved by the local medical ethics committee and by the Institutional Review Board of the International Peace Maternity and Child Health Hospital, Shanghai, China (No. GKLW 2019-08). Participants will sign a written informed consent before participation. The results of this study will be submitted to a peer-reviewed journal for publication.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Trial registration number<\/jats:title>\n                    <jats:p>ChiCTR1900025677.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2020-045770","type":"journal-article","created":{"date-parts":[[2021,8,30]],"date-time":"2021-08-30T12:30:23Z","timestamp":1630326623000},"page":"e045770","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":4,"title":["Comparing levonorgestrel intrauterine system versus hysteroscopic resection in patients with postmenstrual spotting related to a niche in the caesarean scar (MIHYS NICHE trial): protocol of a randomised controlled trial"],"prefix":"10.1136","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6540-2268","authenticated-orcid":false,"given":"Chuqing","family":"He","sequence":"first","affiliation":[{"name":"Department of Obstetrics and Gynecology, International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China"},{"name":"Shanghai Key Laboratory Embryo Original Diseases, Shanghai, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoqing","family":"He","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China"},{"name":"Shanghai Key Laboratory Embryo Original Diseases, Shanghai, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yan","family":"Liang","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China"},{"name":"Shanghai Key Laboratory Embryo Original Diseases, Shanghai, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Taotao","family":"Sun","sequence":"additional","affiliation":[{"name":"Shanghai Key Laboratory Embryo Original Diseases, Shanghai, China"},{"name":"Department of radiology, International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Li","family":"Yan","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China"},{"name":"Shanghai Key Laboratory Embryo Original Diseases, Shanghai, 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