{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,11]],"date-time":"2026-07-11T03:50:09Z","timestamp":1783741809802,"version":"3.55.0"},"reference-count":28,"publisher":"Wiley","issue":"10","license":[{"start":{"date-parts":[[2022,9,7]],"date-time":"2022-09-07T00:00:00Z","timestamp":1662508800000},"content-version":"vor","delay-in-days":6,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["obgyn.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Prenatal Diagnosis"],"published-print":{"date-parts":[[2022,9]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec><jats:title>Objective<\/jats:title><jats:p>Prenatal chorionicity assessment relies on ultrasound, which can be confounded by many factors. Noninvasive assessment of zygosity is possible using single nucleotide polymorphism (SNP)\u2010based cell\u2010free DNA testing. Our objective was to determine the relationship between provider\u2010reported chorionicity and SNP\u2010cfDNA assignment of twin zygosity.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>All twin pregnancy blood samples received by a reference laboratory between September 27, 2017 and September 8, 2021 were included. Chorionicity assignment was requested on the requisition, recorded as; monochorionic (MC), dichorionic, or \u201cdon't know\u201d. SNP\u2010cfDNA zygosity results, monozygotic (MZ) or dizygotic (DZ), were correlated with chorionicity assignment.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>59,471 twin samples (median gestational age\u00a0=\u00a012.0\u00a0weeks at draw) were\u00a0received and analyzed; 55,344 (93.1%) received zygosity assignment. SNP\u2010cfDNA reported 16,673 (30.1%) MZ and 38,671 (69.9%) as DZ. Provider\u2010reported chorionicity was compared to the zygosity assignment for each case. Of 6283 provider\u2010reported MC twins, 318 (5.1%) were reported as DZ using SNP\u2010cfDNA.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusion(s)<\/jats:title><jats:p>One in 20 suspected MC twin pregnancies were reported as DZ using SNP\u2010cfDNA. Approximately 30% of 55,344 twin pregnancies were found to be MZ, including cases where chorionicity was unknown. SNP\u2010cfDNA zygosity assessment is a useful adjunct assessment for twin pregnancies, particularly those reported as MC or without determined chorionicity.<\/jats:p><\/jats:sec>","DOI":"10.1002\/pd.6218","type":"journal-article","created":{"date-parts":[[2022,8,23]],"date-time":"2022-08-23T10:21:27Z","timestamp":1661250087000},"page":"1235-1241","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Clinician\u2010reported chorionicity and zygosity assignment using single\u2010nucleotide polymorphism\u2010based cell\u2010free DNA: Lessons learned from 55,344 twin pregnancies"],"prefix":"10.1002","volume":"42","author":[{"given":"Anna","family":"Wojas","sequence":"first","affiliation":[{"name":"Department of Obstetrics, Gynecology, and Reproductive Science Mt. Sinai  New York NY USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kimberly A.","family":"Martin","sequence":"additional","affiliation":[{"name":"Natera Inc  Austin Texas USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Allyson","family":"Koyen Malashevich","sequence":"additional","affiliation":[{"name":"Natera Inc  Austin Texas USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katelyn","family":"Hashimoto","sequence":"additional","affiliation":[{"name":"Natera Inc  Austin Texas USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sheetal","family":"Parmar","sequence":"additional","affiliation":[{"name":"Natera Inc  Austin Texas USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roseann","family":"White","sequence":"additional","affiliation":[{"name":"Natera Inc  Austin Texas USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8796-2381","authenticated-orcid":false,"given":"Zachary","family":"Demko","sequence":"additional","affiliation":[{"name":"Natera Inc  Austin Texas USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paul","family":"Billings","sequence":"additional","affiliation":[{"name":"Natera Inc  Austin Texas USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Russ","family":"Jelsema","sequence":"additional","affiliation":[{"name":"Natera Inc  Austin Texas USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3528-9652","authenticated-orcid":false,"given":"Andrei","family":"Rebarber","sequence":"additional","affiliation":[{"name":"Department of Obstetrics, Gynecology, and Reproductive Science Mt. Sinai  New York NY USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2022,9,7]]},"reference":[{"key":"e_1_2_11_2_1","doi-asserted-by":"crossref","unstructured":"OstermanMJ HamiltonBE MartinJA DriscollAK ValenzuelaCP.Births: Final Data for 2020;2022.","DOI":"10.15620\/cdc:112078"},{"issue":"4","key":"e_1_2_11_3_1","first-page":"e131","article-title":"Practice bulletin no. 169: multifetal gestations: twin, triplet, and higher\u2010order multifetal pregnancies","volume":"128","author":"Committee on Practice Bulletins\u2010Obstetrics SfM\u2010FM","year":"2016","journal-title":"Obstet Gynecol"},{"key":"e_1_2_11_4_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.12363"},{"key":"e_1_2_11_5_1","doi-asserted-by":"publisher","DOI":"10.1097\/aog.0b013e318187e1ff"},{"key":"e_1_2_11_6_1","doi-asserted-by":"publisher","DOI":"10.1097\/aog.0000000000000599"},{"key":"e_1_2_11_7_1","doi-asserted-by":"publisher","DOI":"10.3390\/jcm8070937"},{"key":"e_1_2_11_8_1","doi-asserted-by":"publisher","DOI":"10.3390\/jcm8091311"},{"key":"e_1_2_11_9_1","doi-asserted-by":"publisher","DOI":"10.1159\/000442931"},{"key":"e_1_2_11_10_1","doi-asserted-by":"publisher","DOI":"10.1002\/pd.3993"},{"key":"e_1_2_11_11_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00431\u2010014\u20102312\u20108"},{"key":"e_1_2_11_12_1","doi-asserted-by":"publisher","DOI":"10.1017\/thg.2017.4"},{"key":"e_1_2_11_13_1","doi-asserted-by":"publisher","DOI":"10.1002\/ajmg.a.35957"},{"key":"e_1_2_11_14_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00381\u2010004\u20100985\u20104"},{"key":"e_1_2_11_15_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.19114"},{"key":"e_1_2_11_16_1","doi-asserted-by":"publisher","DOI":"10.1007\/s10519\u2010016\u20109782\u20106"},{"key":"e_1_2_11_17_1","doi-asserted-by":"publisher","DOI":"10.1046\/j.1469\u20100705.2002.00679.x"},{"key":"e_1_2_11_18_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.8956"},{"key":"e_1_2_11_19_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ejogrb.2016.04.023"},{"key":"e_1_2_11_20_1","doi-asserted-by":"publisher","DOI":"10.7863\/ultra.33.12.2187"},{"key":"e_1_2_11_21_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.13328"},{"key":"e_1_2_11_22_1","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0193476"},{"key":"e_1_2_11_23_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajog.2014.11.041"},{"key":"e_1_2_11_24_1","doi-asserted-by":"publisher","DOI":"10.1097\/01.aog.0000132805.79318.99"},{"key":"e_1_2_11_25_1","doi-asserted-by":"publisher","DOI":"10.1097\/AOG.0000000000003083"},{"key":"e_1_2_11_26_1","doi-asserted-by":"publisher","DOI":"10.1016\/0002\u20109378(93)90605\u2010i"},{"key":"e_1_2_11_27_1","doi-asserted-by":"publisher","DOI":"10.1016\/s0002\u20109378(94)70040\u20100"},{"key":"e_1_2_11_28_1","doi-asserted-by":"publisher","DOI":"10.1097\/aog.0000000000004084"},{"key":"e_1_2_11_29_1","doi-asserted-by":"publisher","DOI":"10.1002\/pd.5832"}],"container-title":["Prenatal Diagnosis"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/pd.6218","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/pd.6218","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/obgyn.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/pd.6218","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,8,23]],"date-time":"2023-08-23T08:19:22Z","timestamp":1692778762000},"score":1,"resource":{"primary":{"URL":"https:\/\/obgyn.onlinelibrary.wiley.com\/doi\/10.1002\/pd.6218"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,9]]},"references-count":28,"journal-issue":{"issue":"10","published-print":{"date-parts":[[2022,9]]}},"alternative-id":["10.1002\/pd.6218"],"URL":"https:\/\/doi.org\/10.1002\/pd.6218","archive":["Portico"],"relation":{},"ISSN":["0197-3851","1097-0223"],"issn-type":[{"value":"0197-3851","type":"print"},{"value":"1097-0223","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,9]]},"assertion":[{"value":"2022-05-10","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2022-07-26","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2022-09-07","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}