{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,22]],"date-time":"2026-06-22T15:10:58Z","timestamp":1782141058826,"version":"3.54.5"},"reference-count":8,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,5,30]],"date-time":"2025-05-30T00:00:00Z","timestamp":1748563200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Med."],"abstract":"<jats:sec><jats:title>Objective<\/jats:title><jats:p>Hyrtl\u2019s anastomosis, an intra-arterial shunt, serves a protective function in singleton placentas. Our team previously documented a case of a monochorionic (MC) twin placenta lacking Hyrtl\u2019s anastomosis. However, research on the impact of absent Hyrtl\u2019s anastomosis in twin placentas remains limited.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>In the present study, we perfused over 70 cases of MC placentas and identified three additional cases exhibiting the same characteristics.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>The absence of Hyrtl\u2019s anastomosis was found to be present in two cases with severe placental territory discordance and one case of a MC triamniotic pregnancy with reversed arterial perfusion sequence, all of which resulted in uneventful pregnancy courses.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusion<\/jats:title><jats:p>The absence of Hyrtl\u2019s anastomosis appears to have a protective effect in MC placentas, contrary to its effect in singleton placentas.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fmed.2025.1575068","type":"journal-article","created":{"date-parts":[[2025,5,30]],"date-time":"2025-05-30T04:10:42Z","timestamp":1748578242000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":2,"title":["Possible protective role of the absence of Hyrtl\u2019s anastomosis in monochorionic pregnancy: exploratory case series"],"prefix":"10.3389","volume":"12","author":[{"given":"Ziling","family":"Liu","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jie","family":"Ruan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2025,5,30]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"939","DOI":"10.2147\/IJWH.S278747","article-title":"Current perspectives of prenatal sonography of umbilical cord morphology","volume":"13","author":"Sherer","year":"2021","journal-title":"Int J Women\u2019s Health"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"597","DOI":"10.1053\/plac.2001.0685","article-title":"In-utero characterization of the blood flow in the Hyrtl anastomosis","volume":"22","author":"Raio","year":"2001","journal-title":"Placenta"},{"key":"ref3","doi-asserted-by":"publisher","first-page":"e33611","DOI":"10.1097\/MD.0000000000033611","article-title":"The role of the absence of Hyrtl\u2019s anastomosis in monochorionic pregnancy: friend or foe?: A case report","volume":"102","author":"Liu","year":"2023","journal-title":"Medicine"},{"key":"ref4","doi-asserted-by":"publisher","first-page":"147","DOI":"10.1038\/sj.jp.7200104","article-title":"Prolonged intermittent reversed end-diastolic flow in a monochorionic twin pregnancy associated with twin-to-twin transfusion syndrome and absence of Hyrtl\u2019s anastomosis","volume":"19","author":"Walker","year":"1999","journal-title":"J Perinatol"},{"key":"ref5","doi-asserted-by":"publisher","first-page":"184","DOI":"10.1017\/thg.2016.29","article-title":"The placenta in twin-to-twin transfusion syndrome and twin anemia polycythemia sequence","volume":"19","author":"Couck","year":"2016","journal-title":"Twin Res Hum Genet"},{"key":"ref6","doi-asserted-by":"publisher","first-page":"10","DOI":"10.1016\/j.placenta.2020.10.012","article-title":"Study of the placental characteristics and time of onset of twin-to-twin transfusion syndrome","volume":"103","author":"Wang","year":"2021","journal-title":"Placenta"},{"key":"ref7","doi-asserted-by":"publisher","first-page":"623","DOI":"10.1111\/jog.13567","article-title":"Roles of venovenous anastomosis and umbilical cord insertion abnormalities in birthweight discordance in monochorionic-diamniotic twin pregnancies without twin-twin transfusion syndrome","volume":"44","author":"Konno","year":"2018","journal-title":"J Obstet Gynaecol Res"},{"key":"ref8","doi-asserted-by":"publisher","first-page":"133","DOI":"10.1016\/j.mri.2023.05.003","article-title":"Fetal-placental MR angiography at 1.5 T and 3 T","volume":"102","author":"Qu","year":"2023","journal-title":"Magn Reson Imaging"}],"container-title":["Frontiers in Medicine"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fmed.2025.1575068\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,5,30]],"date-time":"2025-05-30T04:10:43Z","timestamp":1748578243000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fmed.2025.1575068\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,5,30]]},"references-count":8,"alternative-id":["10.3389\/fmed.2025.1575068"],"URL":"https:\/\/doi.org\/10.3389\/fmed.2025.1575068","relation":{},"ISSN":["2296-858X"],"issn-type":[{"value":"2296-858X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,5,30]]},"article-number":"1575068"}}