{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T10:25:04Z","timestamp":1782210304994,"version":"3.54.5"},"reference-count":33,"publisher":"Georg Thieme Verlag KG","issue":"03","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Ultraschall Med"],"published-print":{"date-parts":[[2021,6]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Twin pregnancies, resulting in 2\u20133\u200a% of all deliveries, are high risk pregnancies which need specialized care. A correct dating of pregnancy and the assessment of the chorionicity\/amnionicity in the first trimester (&lt;\u200a=\u200a13\u200a+\u200a6 gestational weeks, GW) is essential for further monitoring. During first trimester risk stratification of monochorionic pregnancies includes evaluation of discordance of crown-rump-lengths, nuchal translucencies and amniotic fluid. At 16 GW sonographic risk evaluation of monochorionic twins involves differences in amniotic fluid and abdominal circumferences and detection of a velamentous cord insertion. A screening for fetal malformations with cervical length measurement as screening for preterm birth (cut-off &lt;\u200a25\u200amm) should be offered all twin pregnancies around 20 GW. In uncomplicated dichorionic pregnancies US examination should be performed every 4 weeks onwards to check fetal growth and amniotic fluid. An intertwin weight discordance &gt;\u200a20\u200a% identifies pregnancies at increased risk of adverse outcome. Monochorionic pregnancies should be followed at least every two weeks for screening of twin-twin transfusion syndrome (TTTS), twin-anemia-polycythemia-sequence (TAPS) and selective fetal growth retardation (sFGR) with a start at 16 GW. The type 1\u20133 classification of sFGR in monochorionic twins depends on the pattern of end-diastolic velocity at the umbilical artery Doppler. The diagnosis of TTTS requires the presence of an oligyohydramnios (deepest vertical pocket (DVP) &lt;\u200a2\u200acm) in the donor twin and a polyhydramnios (DVP &gt;\u200a8\u200acm) in the recipient twin. However, the diagnosis of TAPS is based on the finding of discordant MCA Doppler values with a delta-MCA PV &gt;\u200a0.5\u200aMoM.<\/jats:p>","DOI":"10.1055\/a-1344-4812","type":"journal-article","created":{"date-parts":[[2021,2,24]],"date-time":"2021-02-24T00:04:22Z","timestamp":1614125062000},"page":"246-269","source":"Crossref","is-referenced-by-count":7,"title":["Twin pregnancies"],"prefix":"10.1055","volume":"42","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7691-965X","authenticated-orcid":false,"given":"Nicole","family":"Ochsenbein-K\u00f6lble","sequence":"additional","affiliation":[{"name":"Department of Obstetrics, University Hospital Z\u00fcrich and\u00a0University of Zurich, Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"194","published-online":{"date-parts":[[2021,2,23]]},"reference":[{"key":"ref2","first-page":"1","article-title":"Births in the United States, 2013","volume":"175","author":"J A Martin","year":"2014","journal-title":"NCHS data brief"},{"key":"ref3","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1186\/1471-2393-12-103","article-title":"Temporal trends in the frequency of twins and higher-order multiple births in Canada and the United States","volume":"12","author":"D B Fell","year":"2012","journal-title":"BMC pregnancy and childbirth"},{"key":"ref4","doi-asserted-by":"publisher","DOI":"10.1055\/a-248-8896","article-title":"Screening, Management and Delivery in Twin Pregnancy","author":"C von Kaisenberg","year":"2020","journal-title":"Ultraschall in Med"},{"key":"ref5","doi-asserted-by":"crossref","first-page":"59","DOI":"10.1016\/j.bpobgyn.2016.09.004","article-title":"Antenatal fetal surveillance in multiple pregnancies","volume":"38","author":"D Oepkes","year":"2017","journal-title":"Best practice & research Clinical obstetrics & gynaecology"},{"key":"ref6","doi-asserted-by":"crossref","first-page":"2187","DOI":"10.7863\/ultra.33.12.2187","article-title":"Accuracy of sonographic chorionicity classification in twin gestations","volume":"33","author":"Y J Blumenfeld","year":"2014","journal-title":"Journal of\u00a0ultrasound in medicine: official journal of the American Institute of Ultrasound in Medicine"},{"key":"ref7","doi-asserted-by":"crossref","first-page":"121","DOI":"10.1159\/000313300","article-title":"Monochorionic diamniotic twin pregnancies: natural history and risk stratification","volume":"27","author":"L Lewi","year":"2010","journal-title":"Fetal diagnosis and therapy"},{"key":"ref8","doi-asserted-by":"crossref","first-page":"242","DOI":"10.1016\/j.ajog.2018.02.010","article-title":"Pitfalls in assessing chorioamnionicity: novel observations and literature review","volume":"219","author":"J Lu","year":"2018","journal-title":"American journal of obstetrics and gynecology"},{"key":"ref9","doi-asserted-by":"crossref","first-page":"470","DOI":"10.1002\/uog.17337","article-title":"Ultrasound and histological measurements of dividing membrane thickness in twin gestations","volume":"50","author":"L A Bracero","year":"2017","journal-title":"Ultrasound in obstetrics & gynecology: the official journal of the International Society of Ultrasound in Obstetrics and Gynecology"},{"key":"ref10","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1002\/pd.2663","article-title":"Current practices in determining amnionicity and chorionicity in multiple gestations","volume":"31","author":"J J Wan","year":"2011","journal-title":"Prenatal diagnosis"},{"key":"ref11","doi-asserted-by":"crossref","first-page":"213.e1","DOI":"10.1016\/j.ajog.2010.04.018","article-title":"The outcome of twin reversed arterial perfusion sequence diagnosed in the first trimester","volume":"203","author":"L Lewi","year":"2010","journal-title":"American journal of obstetrics and gynecology"},{"key":"ref12","doi-asserted-by":"crossref","first-page":"6","DOI":"10.1002\/uog.12495","article-title":"Intrafetal laser treatment for twin reversed arterial perfusion sequence: cohort study and meta-analysis","volume":"42","author":"G Pagani","year":"2013","journal-title":"Ultrasound in obstetrics & gynecology: the official journal of the International Society of Ultrasound in Obstetrics and Gynecology"},{"key":"ref13","doi-asserted-by":"crossref","first-page":"551","DOI":"10.1002\/uog.1897","article-title":"Screening for trisomy 21 in monochorionic twins by measurement of fetal nuchal translucency thickness","volume":"25","author":"H Vandecruys","year":"2005","journal-title":"Ultrasound in obstetrics & gynecology: the official journal of the International Society of Ultrasound in Obstetrics and Gynecology"},{"key":"ref14","doi-asserted-by":"crossref","first-page":"493.e1","DOI":"10.1016\/j.ajog.2008.04.005","article-title":"The role of ultrasound examination in the first trimester and at 16 weeks\u2019 gestation to predict fetal complications in monochorionic diamniotic twin pregnancies","volume":"199","author":"L Lewi","year":"2008","journal-title":"American journal of obstetrics and gynecology"},{"key":"ref15","doi-asserted-by":"crossref","first-page":"385","DOI":"10.1002\/uog.18926","article-title":"Does site of cord insertion increase risk of adverse outcome, twin-to-twin transfusion syndrome and discordant growth in monochorionic twin pregnancy?","volume":"52","author":"I Couck","year":"2018","journal-title":"Ultrasound in obstetrics & gynecology: the official journal of the International Society of Ultrasound in Obstetrics and Gynecology"},{"key":"ref16","doi-asserted-by":"crossref","first-page":"511.e1","DOI":"10.1016\/j.ajog.2008.04.022","article-title":"Clinical outcome and placental characteristics of monochorionic diamniotic twin pairs with early- and late-onset discordant growth","volume":"199","author":"L Lewi","year":"2008","journal-title":"American journal of obstetrics and gynecology"},{"key":"ref17","doi-asserted-by":"crossref","first-page":"1114","DOI":"10.1136\/jech-2015-206302","article-title":"Twinning and major birth defects, National Birth Defects Prevention Study, 1997-2007","volume":"70","author":"A L Dawson","year":"2016","journal-title":"Journal of epidemiology and community health"},{"key":"ref18","doi-asserted-by":"crossref","first-page":"247","DOI":"10.1002\/uog.15821","article-title":"ISUOG Practice Guidelines: role of ultrasound in twin pregnancy","volume":"47","author":"A Khalil","year":"2016","journal-title":"Ultrasound in obstetrics & gynecology: the official journal of the International Society of Ultrasound in Obstetrics and Gynecology"},{"key":"ref19","doi-asserted-by":"crossref","first-page":"586.e1","DOI":"10.1016\/j.ajog.2013.10.005","article-title":"Healthcare expenses associated with multiple vs singleton pregnancies in the United States","volume":"209","author":"E V Lemos","year":"2013","journal-title":"American journal of obstetrics and gynecology"},{"key":"ref20","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1002\/uog.18966","article-title":"Weight discordance and perinatal mortality in twin pregnancy: systematic review and meta-analysis","volume":"52","author":"F D\u2019Antonio","year":"2018","journal-title":"Ultrasound in obstetrics & gynecology: the official journal of the International Society of Ultrasound in Obstetrics and Gynecology"},{"key":"ref21","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1002\/uog.19013","article-title":"Consensus definition and essential reporting parameters of selective fetal growth restriction in twin pregnancy: a Delphi procedure","volume":"53","author":"A Khalil","year":"2019","journal-title":"Ultrasound in obstetrics & gynecology: the official journal of the International Society of Ultrasound in Obstetrics and Gynecology"},{"key":"ref22","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1002\/uog.4046","article-title":"A classification system for selective intrauterine growth restriction in monochorionic pregnancies according to umbilical artery Doppler flow in the\u00a0smaller twin","volume":"30","author":"E Gratacos","year":"2007","journal-title":"Ultrasound in obstetrics & gynecology: the official journal of the International Society of Ultrasound in Obstetrics and Gynecology"},{"key":"ref23","doi-asserted-by":"crossref","first-page":"559","DOI":"10.1002\/uog.17362","article-title":"Outcome of monochorionic twin pregnancy with selective intrauterine growth restriction according to umbilical artery Doppler flow pattern of smaller twin: systematic review and meta-analysis","volume":"50","author":"D Buca","year":"2017","journal-title":"Ultrasound in obstetrics & gynecology: the official journal of the International Society of Ultrasound in Obstetrics and Gynecology"},{"key":"ref24","doi-asserted-by":"crossref","first-page":"376","DOI":"10.1016\/j.siny.2017.05.001","article-title":"Selective intrauterine growth restriction in monochorionic diamniotic twin pregnancies","volume":"22","author":"M Bennasar","year":"2017","journal-title":"Seminars in fetal & neonatal medicine"},{"key":"ref25","doi-asserted-by":"crossref","first-page":"550","DOI":"10.1038\/sj.jp.7200292","article-title":"Staging of twin-twin transfusion syndrome","volume":"19","author":"R A Quintero","year":"1999","journal-title":"Journal of perinatology: official journal of the California Perinatal Association"},{"key":"ref26","first-page":"Cd002073","article-title":"Interventions for the treatment of twin-twin transfusion syndrome","volume":"1","author":"D Roberts","year":"2014","journal-title":"The Cochrane database of systematic reviews"},{"key":"ref27","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1159\/000341814","article-title":"Cerebral injury and neurodevelopmental impairment after amnioreduction versus laser surgery in twin-twin transfusion syndrome: a systematic review and meta-analysis","volume":"33","author":"J M van Klink","year":"2013","journal-title":"Fetal diagnosis and therapy"},{"key":"ref28","doi-asserted-by":"crossref","first-page":"255","DOI":"10.1017\/thg.2016.26","article-title":"Long-Term Neurodevelopmental Outcome in Survivors of Twin-to-Twin Transfusion Syndrome","volume":"19","author":"J M van Klink","year":"2016","journal-title":"Twin research and human genetics: the official journal of the International Society for Twin Studies"},{"key":"ref29","first-page":"5","article-title":"Survival outcomes of twin-twin transfusion syndrome stage I: a systematic review of literature","volume":"30","author":"A C Rossi","year":"2013","journal-title":"American journal of perinatology"},{"key":"ref30","doi-asserted-by":"crossref","first-page":"2144","DOI":"10.1016\/S0140-6736(13)62419-8","article-title":"Fetoscopic laser coagulation of the vascular equator versus selective coagulation for twin-to-twin transfusion syndrome: an open-label randomised controlled trial","volume":"383","author":"F Slaghekke","year":"2014","journal-title":"Lancet (London, England)"},{"key":"ref31","doi-asserted-by":"crossref","first-page":"222","DOI":"10.1017\/thg.2016.18","article-title":"Twin Anemia Polycythemia Sequence: Current Views on Pathogenesis, Diagnostic Criteria, Perinatal Management, and Outcome","volume":"19","author":"L S Tollenaar","year":"2016","journal-title":"Twin research and human genetics: the official journal of the International Society for Twin Studies"},{"key":"ref32","doi-asserted-by":"crossref","first-page":"316","DOI":"10.1002\/uog.13387","article-title":"Neurodevelopmental outcome in twin anemia-polycythemia sequence after laser surgery for twin-twin transfusion syndrome","volume":"44","author":"F Slaghekke","year":"2014","journal-title":"Ultrasound in obstetrics & gynecology: the official journal of the International Society of Ultrasound in Obstetrics and Gynecology"},{"key":"ref33","doi-asserted-by":"crossref","first-page":"788","DOI":"10.1002\/uog.20096","article-title":"Improved prediction of twin anemia-polycythemia sequence by delta middle cerebral artery peak systolic velocity: new antenatal classification system","volume":"53","author":"L SA Tollenaar","year":"2019","journal-title":"Ultrasound in obstetrics & gynecology: the official journal of the International Society of Ultrasound in Obstetrics and Gynecology"},{"key":"ref34","doi-asserted-by":"crossref","first-page":"166","DOI":"10.1002\/uog.20100","article-title":"Perinatal mortality, timing of delivery and prenatal management of monoamniotic twin pregnancy: systematic review and meta-analysis","volume":"53","author":"F D\u2019Antonio","year":"2019","journal-title":"Ultrasound in obstetrics & gynecology: the official journal of the International Society of Ultrasound in Obstetrics and Gynecology"}],"container-title":["Ultraschall in der Medizin - European Journal of Ultrasound"],"original-title":[],"language":"de","link":[{"URL":"http:\/\/www.thieme-connect.de\/products\/ejournals\/pdf\/10.1055\/a-1344-4812.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,6,15]],"date-time":"2021-06-15T22:34:41Z","timestamp":1623796481000},"score":1,"resource":{"primary":{"URL":"http:\/\/www.thieme-connect.de\/DOI\/DOI?10.1055\/a-1344-4812"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,2,23]]},"references-count":33,"journal-issue":{"issue":"03","published-online":{"date-parts":[[2021,6,15]]},"published-print":{"date-parts":[[2021,6]]}},"URL":"https:\/\/doi.org\/10.1055\/a-1344-4812","archive":["Portico","CLOCKSS"],"relation":{},"ISSN":["0172-4614","1438-8782"],"issn-type":[{"value":"0172-4614","type":"print"},{"value":"1438-8782","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,2,23]]}}}